Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.
The diffusion or accumulation of neutrophils in tissues or cells in response to a wide variety of substances released at the sites of inflammatory reactions.
A formylated tripeptide originally isolated from bacterial filtrates that is positively chemotactic to polymorphonuclear leucocytes, and causes them to release lysosomal enzymes and become metabolically activated.
The movement of leukocytes in response to a chemical concentration gradient or to products formed in an immunologic reaction.
A hemeprotein from leukocytes. Deficiency of this enzyme leads to a hereditary disorder coupled with disseminated moniliasis. It catalyzes the conversion of a donor and peroxide to an oxidized donor and water. EC
Cell-surface glycoprotein beta-chains that are non-covalently linked to specific alpha-chains of the CD11 family of leukocyte-adhesion molecules (RECEPTORS, LEUKOCYTE-ADHESION). A defect in the gene encoding CD18 causes LEUKOCYTE-ADHESION DEFICIENCY SYNDROME.
The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (PHAGOCYTES).
Highly reactive compounds produced when oxygen is reduced by a single electron. In biological systems, they may be generated during the normal catalytic function of a number of enzymes and during the oxidation of hemoglobin to METHEMOGLOBIN. In living organisms, SUPEROXIDE DISMUTASE protects the cell from the deleterious effects of superoxides.
Chemical substances that attract or repel cells. The concept denotes especially those factors released as a result of tissue injury, microbial invasion, or immunologic activity, that attract LEUKOCYTES; MACROPHAGES; or other cells to the site of infection or insult.
An adhesion-promoting leukocyte surface membrane heterodimer. The alpha subunit consists of the CD11b ANTIGEN and the beta subunit the CD18 ANTIGEN. The antigen, which is an integrin, functions both as a receptor for complement 3 and in cell-cell and cell-substrate adhesive interactions.
A member of the CXC chemokine family that plays a role in the regulation of the acute inflammatory response. It is secreted by variety of cell types and induces CHEMOTAXIS of NEUTROPHILS and other inflammatory cells.
The major metabolite in neutrophil polymorphonuclear leukocytes. It stimulates polymorphonuclear cell function (degranulation, formation of oxygen-centered free radicals, arachidonic acid release, and metabolism). (From Dictionary of Prostaglandins and Related Compounds, 1990)
The number of WHITE BLOOD CELLS per unit volume in venous BLOOD. A differential leukocyte count measures the relative numbers of the different types of white cells.
Adherence of cells to surfaces or to other cells.
A protease of broad specificity, obtained from dried pancreas. Molecular weight is approximately 25,000. The enzyme breaks down elastin, the specific protein of elastic fibers, and digests other proteins such as fibrin, hemoglobin, and albumin. EC
A serine protease found in the azurophil granules of NEUTROPHILS. It has an enzyme specificity similar to that of chymotrypsin C.
A CXC chemokine with specificity for CXCR2 RECEPTORS. It has growth factor activities and is implicated as a oncogenic factor in several tumor types.
High-affinity G-protein-coupled receptors for INTERLEUKIN-8 present on NEUTROPHILS; MONOCYTES; and T-LYMPHOCYTES. These receptors also bind several other CXC CHEMOKINES.
The minor fragment formed when C5 convertase cleaves C5 into C5a and COMPLEMENT C5B. C5a is a 74-amino-acid glycopeptide with a carboxy-terminal ARGININE that is crucial for its spasmogenic activity. Of all the complement-derived anaphylatoxins, C5a is the most potent in mediating immediate hypersensitivity (HYPERSENSITIVITY, IMMEDIATE), smooth MUSCLE CONTRACTION; HISTAMINE RELEASE; and migration of LEUKOCYTES to site of INFLAMMATION.
A pathological process characterized by injury or destruction of tissues caused by a variety of cytologic and chemical reactions. It is usually manifested by typical signs of pain, heat, redness, swelling, and loss of function.
A flavoprotein enzyme that catalyzes the univalent reduction of OXYGEN using NADPH as an electron donor to create SUPEROXIDE ANION. The enzyme is dependent on a variety of CYTOCHROMES. Defects in the production of superoxide ions by enzymes such as NADPH oxidase result in GRANULOMATOUS DISEASE, CHRONIC.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
A CXC chemokine that is synthesized by activated MONOCYTES and NEUTROPHILS. It has specificity for CXCR2 RECEPTORS.
A defect of leukocyte function in which phagocytic cells ingest but fail to digest bacteria, resulting in recurring bacterial infections with granuloma formation. When chronic granulomatous disease is caused by mutations in the CYBB gene, the condition is inherited in an X-linked recessive pattern. When chronic granulomatous disease is caused by CYBA, NCF1, NCF2, or NCF4 gene mutations, the condition is inherited in an autosomal recessive pattern.
A family of G-protein-coupled receptors that was originally identified by its ability to bind N-formyl peptides such as N-FORMYLMETHIONINE LEUCYL-PHENYLALANINE. Since N-formyl peptides are found in MITOCHONDRIA and BACTERIA, this class of receptors is believed to play a role in mediating cellular responses to cellular damage and bacterial invasion. However, non-formylated peptide ligands have also been found for this receptor class.
The movement of cells from one location to another. Distinguish from CYTOKINESIS which is the process of dividing the CYTOPLASM of a cell.
Condensed areas of cellular material that may be bounded by a membrane.
Lipid-containing polysaccharides which are endotoxins and important group-specific antigens. They are often derived from the cell wall of gram-negative bacteria and induce immunoglobulin secretion. The lipopolysaccharide molecule consists of three parts: LIPID A, core polysaccharide, and O-specific chains (O ANTIGENS). When derived from Escherichia coli, lipopolysaccharides serve as polyclonal B-cell mitogens commonly used in laboratory immunology. (From Dorland, 28th ed)
Cell adhesion molecule and CD antigen that serves as a homing receptor for lymphocytes to lymph node high endothelial venules.
Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.
A phorbol ester found in CROTON OIL with very effective tumor promoting activity. It stimulates the synthesis of both DNA and RNA.
The process of losing secretory granules (SECRETORY VESICLES). This occurs, for example, in mast cells, basophils, neutrophils, eosinophils, and platelets when secretory products are released from the granules by EXOCYTOSIS.
A polymorphonuclear leukocyte-derived serine protease that degrades proteins such as ELASTIN; FIBRONECTIN; LAMININ; VITRONECTIN; and COLLAGEN. It is named for its ability to control myeloid cell growth and differentiation.
Techniques used for determining the values of photometric parameters of light resulting from LUMINESCENCE.
Washing liquid obtained from irrigation of the lung, including the BRONCHI and the PULMONARY ALVEOLI. It is generally used to assess biochemical, inflammatory, or infection status of the lung.
DEFENSINS found in azurophilic granules of neutrophils and in the secretory granules of intestinal PANETH CELLS.
A phospholipid derivative formed by PLATELETS; BASOPHILS; NEUTROPHILS; MONOCYTES; and MACROPHAGES. It is a potent platelet aggregating agent and inducer of systemic anaphylactic symptoms, including HYPOTENSION; THROMBOCYTOPENIA; NEUTROPENIA; and BRONCHOCONSTRICTION.
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
A glycoprotein of MW 25 kDa containing internal disulfide bonds. It induces the survival, proliferation, and differentiation of neutrophilic granulocyte precursor cells and functionally activates mature blood neutrophils. Among the family of colony-stimulating factors, G-CSF is the most potent inducer of terminal differentiation to granulocytes and macrophages of leukemic myeloid cell lines.
White blood cells. These include granular leukocytes (BASOPHILS; EOSINOPHILS; and NEUTROPHILS) as well as non-granular leukocytes (LYMPHOCYTES and MONOCYTES).
Serum glycoprotein produced by activated MACROPHAGES and other mammalian MONONUCLEAR LEUKOCYTES. It has necrotizing activity against tumor cell lines and increases ability to reject tumor transplants. Also known as TNF-alpha, it is only 30% homologous to TNF-beta (LYMPHOTOXIN), but they share TNF RECEPTORS.
The natural bactericidal property of BLOOD due to normally occurring antibacterial substances such as beta lysin, leukin, etc. This activity needs to be distinguished from the bactericidal activity contained in a patient's serum as a result of antimicrobial therapy, which is measured by a SERUM BACTERICIDAL TEST.
A CD antigen that contains a conserved I domain which is involved in ligand binding. When combined with CD18 the two subunits form MACROPHAGE-1 ANTIGEN.
High-affinity G-protein-coupled receptors for INTERLEUKIN-8 present on NEUTROPHILS; MONOCYTES; and BASOPHILS.
Specific molecular sites on the surface of various cells, including B-lymphocytes and macrophages, that combine with IMMUNOGLOBULIN Gs. Three subclasses exist: Fc gamma RI (the CD64 antigen, a low affinity receptor), Fc gamma RII (the CD32 antigen, a high affinity receptor), and Fc gamma RIII (the CD16 antigen, a low affinity receptor).
A promyelocytic cell line derived from a patient with ACUTE PROMYELOCYTIC LEUKEMIA. HL-60 cells lack specific markers for LYMPHOID CELLS but express surface receptors for FC FRAGMENTS and COMPLEMENT SYSTEM PROTEINS. They also exhibit phagocytic activity and responsiveness to chemotactic stimuli. (From Hay et al., American Type Culture Collection, 7th ed, pp127-8)
Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.
Class of pro-inflammatory cytokines that have the ability to attract and activate leukocytes. They can be divided into at least three structural branches: C; (CHEMOKINES, C); CC; (CHEMOKINES, CC); and CXC; (CHEMOKINES, CXC); according to variations in a shared cysteine motif.
An iron-binding protein that was originally characterized as a milk protein. It is widely distributed in secretory fluids and is found in the neutrophilic granules of LEUKOCYTES. The N-terminal part of lactoferrin possesses a serine protease which functions to inactivate the TYPE III SECRETION SYSTEM used by bacteria to export virulence proteins for host cell invasion.
A diverse family of extracellular proteins that bind to small hydrophobic molecules. They were originally characterized as transport proteins, however they may have additional roles such as taking part in the formation of macromolecular complexes with other proteins and binding to CELL SURFACE RECEPTORS.
An acidic glycoprotein of MW 23 kDa with internal disulfide bonds. The protein is produced in response to a number of inflammatory mediators by mesenchymal cells present in the hemopoietic environment and at peripheral sites of inflammation. GM-CSF is able to stimulate the production of neutrophilic granulocytes, macrophages, and mixed granulocyte-macrophage colonies from bone marrow cells and can stimulate the formation of eosinophil colonies from fetal liver progenitor cells. GM-CSF can also stimulate some functional activities in mature granulocytes and macrophages.
A decrease in the number of NEUTROPHILS found in the blood.
Disordered formation of various types of leukocytes or an abnormal accumulation or deficiency of these cells.
A cytotoxic member of the CYTOCHALASINS.
The movement of cells or organisms toward or away from a substance in response to its concentration gradient.
An oxyacid of chlorine (HClO) containing monovalent chlorine that acts as an oxidizing or reducing agent.
Group of chemokines with paired cysteines separated by a different amino acid. CXC chemokines are chemoattractants for neutrophils but not monocytes.
Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner.
Cell adhesion molecule and CD antigen that mediates the adhesion of neutrophils and monocytes to activated platelets and endothelial cells.
Granular leukocytes with a nucleus that usually has two lobes connected by a slender thread of chromatin, and cytoplasm containing coarse, round granules that are uniform in size and stainable by eosin.
Large, phagocytic mononuclear leukocytes produced in the vertebrate BONE MARROW and released into the BLOOD; contain a large, oval or somewhat indented nucleus surrounded by voluminous cytoplasm and numerous organelles.
Proteins that bind to particles and cells to increase susceptibility to PHAGOCYTOSIS, especially ANTIBODIES bound to EPITOPES that attach to FC RECEPTORS. COMPLEMENT C3B may also participate.
The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)
One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.
Leukocytes with abundant granules in the cytoplasm. They are divided into three groups according to the staining properties of the granules: neutrophilic, eosinophilic, and basophilic. Mature granulocytes are the NEUTROPHILS; EOSINOPHILS; and BASOPHILS.
Surface ligands, usually glycoproteins, that mediate cell-to-cell adhesion. Their functions include the assembly and interconnection of various vertebrate systems, as well as maintenance of tissue integration, wound healing, morphogenic movements, cellular migrations, and metastasis.
A group of oxidoreductases that act on NADH or NADPH. In general, enzymes using NADH or NADPH to reduce a substrate are classified according to the reverse reaction, in which NAD+ or NADP+ is formally regarded as an acceptor. This subclass includes only those enzymes in which some other redox carrier is the acceptor. (Enzyme Nomenclature, 1992, p100) EC 1.6.
Molecules or ions formed by the incomplete one-electron reduction of oxygen. These reactive oxygen intermediates include SINGLET OXYGEN; SUPEROXIDES; PEROXIDES; HYDROXYL RADICAL; and HYPOCHLOROUS ACID. They contribute to the microbicidal activity of PHAGOCYTES, regulation of signal transduction and gene expression, and the oxidative damage to NUCLEIC ACIDS; PROTEINS; and LIPIDS.
A group of three different alpha chains (CD11a, CD11b, CD11c) that are associated with an invariant CD18 beta chain (ANTIGENS, CD18). The three resulting leukocyte-adhesion molecules (RECEPTORS, LEUKOCYTE ADHESION) are LYMPHOCYTE FUNCTION-ASSOCIATED ANTIGEN-1; MACROPHAGE-1 ANTIGEN; and ANTIGEN, P150,95.
Differentiation antigens residing on mammalian leukocytes. CD stands for cluster of differentiation, which refers to groups of monoclonal antibodies that show similar reactivity with certain subpopulations of antigens of a particular lineage or differentiation stage. The subpopulations of antigens are also known by the same CD designation.
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
A cell-surface ligand involved in leukocyte adhesion and inflammation. Its production is induced by gamma-interferon and it is required for neutrophil migration into inflamed tissue.
Elements of limited time intervals, contributing to particular results or situations.
Proteins that are secreted into the blood in increased or decreased quantities by hepatocytes in response to trauma, inflammation, or disease. These proteins can serve as inhibitors or mediators of the inflammatory processes. Certain acute-phase proteins have been used to diagnose and follow the course of diseases or as tumor markers.
The passage of cells across the layer of ENDOTHELIAL CELLS, i.e., the ENDOTHELIUM; or across the layer of EPITHELIAL CELLS, i.e. the EPITHELIUM.
Antibodies produced by a single clone of cells.
Movement of tethered, spherical LEUKOCYTES along the endothelial surface of the microvasculature. The tethering and rolling involves interaction with SELECTINS and other adhesion molecules in both the ENDOTHELIUM and leukocyte. The rolling leukocyte then becomes activated by CHEMOKINES, flattens out, and firmly adheres to the endothelial surface in preparation for transmigration through the interendothelial cell junction. (From Abbas, Cellular and Molecular Immunology, 3rd ed)
C5 plays a central role in both the classical and the alternative pathway of COMPLEMENT ACTIVATION. C5 is cleaved by C5 CONVERTASE into COMPLEMENT C5A and COMPLEMENT C5B. The smaller fragment C5a is an ANAPHYLATOXIN and mediator of inflammatory process. The major fragment C5b binds to the membrane initiating the spontaneous assembly of the late complement components, C5-C9, into the MEMBRANE ATTACK COMPLEX.
Proteins prepared by recombinant DNA technology.
Autoantibodies directed against cytoplasmic constituents of POLYMORPHONUCLEAR LEUKOCYTES and/or MONOCYTES. They are used as specific markers for GRANULOMATOSIS WITH POLYANGIITIS and other diseases, though their pathophysiological role is not clear. ANCA are routinely detected by indirect immunofluorescence with three different patterns: c-ANCA (cytoplasmic), p-ANCA (perinuclear), and atypical ANCA.
Family of antimicrobial peptides that have been identified in humans, animals, and plants. They are thought to play a role in host defenses against infections, inflammation, wound repair, and acquired immunity.
The rate dynamics in chemical or physical systems.
A member of the MATRIX METALLOPROTEINASES that cleaves triple-helical COLLAGEN types I, II, and III.
A group of lysosomal proteinases or endopeptidases found in aqueous extracts of a variety of animal tissues. They function optimally within an acidic pH range. The cathepsins occur as a variety of enzyme subtypes including SERINE PROTEASES; ASPARTIC PROTEINASES; and CYSTEINE PROTEASES.
INFLAMMATION of the PERITONEUM lining the ABDOMINAL CAVITY as the result of infectious, autoimmune, or chemical processes. Primary peritonitis is due to infection of the PERITONEAL CAVITY via hematogenous or lymphatic spread and without intra-abdominal source. Secondary peritonitis arises from the ABDOMINAL CAVITY itself through RUPTURE or ABSCESS of intra-abdominal organs.
Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.
Molecules on the surface of some B-lymphocytes and macrophages, that recognize and combine with the C3b, C3d, C1q, and C4b components of complement.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
Effective in the initiation of protein synthesis. The initiating methionine residue enters the ribosome as N-formylmethionyl tRNA. This process occurs in Escherichia coli and other bacteria as well as in the mitochondria of eucaryotic cells.
A strong oxidizing agent used in aqueous solution as a ripening agent, bleach, and topical anti-infective. It is relatively unstable and solutions deteriorate over time unless stabilized by the addition of acetanilide or similar organic materials.
The relationship between the dose of an administered drug and the response of the organism to the drug.
Single pavement layer of cells which line the luminal surface of the entire vascular system and regulate the transport of macromolecules and blood components.
Family of proteins associated with the capacity of LEUKOCYTES to adhere to each other and to certain substrata, e.g., the C3bi component of complement. Members of this family are the LYMPHOCYTE FUNCTION-ASSOCIATED ANTIGEN-1; (LFA-1), the MACROPHAGE-1 ANTIGEN; (Mac-1), and the INTEGRIN ALPHAXBETA2 or p150,95 leukocyte adhesion protein. They all share a common beta-subunit which is the CD18 antigen. All three of the above antigens are absent in inherited LEUKOCYTE-ADHESION DEFICIENCY SYNDROME, which is characterized by recurrent bacterial infections, impaired pus formation, and wound healing as well as abnormalities in a wide spectrum of adherence-dependent functions of granulocytes, monocytes, and lymphoid cells.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
The phenomenon by which dissociated cells intermixed in vitro tend to group themselves with cells of their own type.
Soluble mediators of the immune response that are neither antibodies nor complement. They are produced largely, but not exclusively, by monocytes and macrophages.
Assays that measure the rate of migration of LEUKOCYTES. They may involve a variety of techniques such as measuring the movement of leukocytes through substrates such as AGAROSE gels or the rate of exit of cells from a glass capillary.
Infection of the lung often accompanied by inflammation.
Colorless to yellow dye that is reducible to blue or black formazan crystals by certain cells; formerly used to distinguish between nonbacterial and bacterial diseases, the latter causing neutrophils to reduce the dye; used to confirm diagnosis of chronic granulomatous disease.
Any member of the group of ENDOPEPTIDASES containing at the active site a serine residue involved in catalysis.
Cell adhesion molecule and CD antigen that mediates neutrophil, monocyte, and memory T-cell adhesion to cytokine-activated endothelial cells. E-selectin recognizes sialylated carbohydrate groups related to the Lewis X or Lewis A family.
A CXC chemokine that is predominantly expressed in EPITHELIAL CELLS. It has specificity for the CXCR2 RECEPTORS and is involved in the recruitment and activation of NEUTROPHILS.
A class of cell surface leukotriene receptors with a preference for leukotriene B4. Leukotriene B4 receptor activation influences chemotaxis, chemokinesis, adherence, enzyme release, oxidative bursts, and degranulation in polymorphonuclear leukocytes. There are at least two subtypes of these receptors. Some actions are mediated through the inositol phosphate and diacylglycerol second messenger systems.
The capacity of a normal organism to remain unaffected by microorganisms and their toxins. It results from the presence of naturally occurring ANTI-INFECTIVE AGENTS, constitutional factors such as BODY TEMPERATURE and immediate acting immune cells such as NATURAL KILLER CELLS.
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
Cytochromes (electron-transporting proteins) with protoheme (HEME B) as the prosthetic group.
The endogenous compounds that mediate inflammation (AUTACOIDS) and related exogenous compounds including the synthetic prostaglandins (PROSTAGLANDINS, SYNTHETIC).
Plasma glycoprotein member of the serpin superfamily which inhibits TRYPSIN; NEUTROPHIL ELASTASE; and other PROTEOLYTIC ENZYMES.
Glycoproteins found on the membrane or surface of cells.
Proteins that are present in blood serum, including SERUM ALBUMIN; BLOOD COAGULATION FACTORS; and many other types of proteins.
The space enclosed by the peritoneum. It is divided into two portions, the greater sac and the lesser sac or omental bursa, which lies behind the STOMACH. The two sacs are connected by the foramen of Winslow, or epiploic foramen.
Cells that can carry out the process of PHAGOCYTOSIS.
A 13.2-kDa member of the S-100 family of calcium-binding proteins that can form homo- or heterocomplexes with CALGRANULIN A and a variety of other proteins. The calgranulin A/B heterodimer is known as LEUKOCYTE L1 ANTIGEN COMPLEX. Calgranulin B is expressed at high concentrations in GRANULOCYTES during early monocyte differentiation, and serum calgranulin B levels are elevated in many inflammatory disorders such as CYSTIC FIBROSIS.
An ionophorous, polyether antibiotic from Streptomyces chartreusensis. It binds and transports CALCIUM and other divalent cations across membranes and uncouples oxidative phosphorylation while inhibiting ATPase of rat liver mitochondria. The substance is used mostly as a biochemical tool to study the role of divalent cations in various biological systems.
Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.
Molecular sites on or in some B-lymphocytes and macrophages that recognize and combine with COMPLEMENT C3B. The primary structure of these receptors reveal that they contain transmembrane and cytoplasmic domains, with their extracellular portion composed entirely of thirty short consensus repeats each having 60 to 70 amino acids.
A subclass of lipid-linked proteins that contain a GLYCOSYLPHOSPHATIDYLINOSITOL LINKAGE which holds them to the CELL MEMBRANE.
Adverse functional, metabolic, or structural changes in ischemic tissues resulting from the restoration of blood flow to the tissue (REPERFUSION), including swelling; HEMORRHAGE; NECROSIS; and damage from FREE RADICALS. The most common instance is MYOCARDIAL REPERFUSION INJURY.
Cell surface molecules on cells of the immune system that specifically bind surface molecules or messenger molecules and trigger changes in the behavior of cells. Although these receptors were first identified in the immune system, many have important functions elsewhere.
A soluble factor produced by MONOCYTES; MACROPHAGES, and other cells which activates T-lymphocytes and potentiates their response to mitogens or antigens. Interleukin-1 is a general term refers to either of the two distinct proteins, INTERLEUKIN-1ALPHA and INTERLEUKIN-1BETA. The biological effects of IL-1 include the ability to replace macrophage requirements for T-cell activation.
Systemic inflammatory response syndrome with a proven or suspected infectious etiology. When sepsis is associated with organ dysfunction distant from the site of infection, it is called severe sepsis. When sepsis is accompanied by HYPOTENSION despite adequate fluid infusion, it is called SEPTIC SHOCK.
A G-protein-coupled receptor that signals an increase in intracellular calcium in response to the potent ANAPHYLATOXIN peptide COMPLEMENT C5A.
A condition of lung damage that is characterized by bilateral pulmonary infiltrates (PULMONARY EDEMA) rich in NEUTROPHILS, and in the absence of clinical HEART FAILURE. This can represent a spectrum of pulmonary lesions, endothelial and epithelial, due to numerous factors (physical, chemical, or biological).
Organic esters of thioglycolic acid (HS-CH2COOH).
Phenomenon of cell-mediated immunity measured by in vitro inhibition of the migration or phagocytosis of antigen-stimulated LEUKOCYTES or MACROPHAGES. Specific CELL MIGRATION ASSAYS have been developed to estimate levels of migration inhibitory factors, immune reactivity against tumor-associated antigens, and immunosuppressive effects of infectious microorganisms.
Cell surface proteins that bind LIPOXINS with high affinity and trigger intracellular changes influencing the behavior of cells.
A positive regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.
A 10.8-kDa member of the S-100 family of calcium-binding proteins that can form homo- or heterocomplexes with CALGRANULIN B and a variety of other proteins. The calgranulin A/B heterodimer is known as LEUKOCYTE L1 ANTIGEN COMPLEX. Calgranulin A is found in many cell types including GRANULOCYTES; KERATINOCYTES; and myelomonocytes, and has been shown to act as a chemotactic substance for NEUTROPHILS. Because it is present in acute inflammation but absent in chronic inflammation, it is a useful biological marker for a number of pathological conditions.
Eicosatetraenoic acids substituted in any position by one or more hydroxy groups. They are important intermediates in a series of biosynthetic processes leading from arachidonic acid to a number of biologically active compounds such as prostaglandins, thromboxanes, and leukotrienes.
Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.
Potentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.
The complex formed by the binding of antigen and antibody molecules. The deposition of large antigen-antibody complexes leading to tissue damage causes IMMUNE COMPLEX DISEASES.
Rare, autosomal recessive disorder caused by deficiency of the beta 2 integrin receptors (RECEPTORS, LEUKOCYTE-ADHESION) comprising the CD11/CD18 family of glycoproteins. The syndrome is characterized by abnormal adhesion-dependent functions, especially defective tissue emigration of neutrophils, leading to recurrent infection.
Molecules found on the surface of some, but not all, B-lymphocytes, T-lymphocytes, and macrophages, which recognize and combine with the Fc (crystallizable) portion of immunoglobulin molecules.
An enzyme that catalyzes the oxidation of arachidonic acid to yield 5-hydroperoxyarachidonate (5-HPETE) which is rapidly converted by a peroxidase to 5-hydroxy-6,8,11,14-eicosatetraenoate (5-HETE). The 5-hydroperoxides are preferentially formed in leukocytes.
The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.
An integrin heterodimer widely expressed on cells of hematopoietic origin. CD11A ANTIGEN comprises the alpha chain and the CD18 antigen (ANTIGENS, CD18) the beta chain. Lymphocyte function-associated antigen-1 is a major receptor of T-CELLS; B-CELLS; and GRANULOCYTES. It mediates the leukocyte adhesion reactions underlying cytolytic conjugate formation, helper T-cell interactions, and antibody-dependent killing by NATURAL KILLER CELLS and granulocytes. Intracellular adhesion molecule-1 has been defined as a ligand for lymphocyte function-associated antigen-1.
A technique to study CELL MIGRATION in the INFLAMMATION process or during immune reactions. After an area on the skin is abraded, the movement of cells in the area is followed via microscopic observation of the exudate through a coverslip or tissue culture chamber placed over the area.
Substances that reduce or suppress INFLAMMATION.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
The number of LEUKOCYTES and ERYTHROCYTES per unit volume in a sample of venous BLOOD. A complete blood count (CBC) also includes measurement of the HEMOGLOBIN; HEMATOCRIT; and ERYTHROCYTE INDICES.
A dermal inflammatory reaction produced under conditions of antibody excess, when a second injection of antigen produces intravascular antigen-antibody complexes which bind complement, causing cell clumping, endothelial damage, and vascular necrosis.
Round, granular, mononuclear phagocytes found in the alveoli of the lungs. They ingest small inhaled particles resulting in degradation and presentation of the antigen to immunocompetent cells.
Inflammation of the lung parenchyma that is caused by bacterial infections.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
Non-nucleated disk-shaped cells formed in the megakaryocyte and found in the blood of all mammals. They are mainly involved in blood coagulation.
Exogenous or endogenous compounds which inhibit SERINE ENDOPEPTIDASES.
Cells contained in the bone marrow including fat cells (see ADIPOCYTES); STROMAL CELLS; MEGAKARYOCYTES; and the immediate precursors of most blood cells.
Trihydroxy derivatives of eicosanoic acids. They are primarily derived from arachidonic acid, however eicosapentaenoic acid derivatives also exist. Many of them are naturally occurring mediators of immune regulation.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.
An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.
Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.
Small cationic peptides that are an important component, in most species, of early innate and induced defenses against invading microbes. In animals they are found on mucosal surfaces, within phagocytic granules, and on the surface of the body. They are also found in insects and plants. Among others, this group includes the DEFENSINS, protegrins, tachyplesins, and thionins. They displace DIVALENT CATIONS from phosphate groups of MEMBRANE LIPIDS leading to disruption of the membrane.
Transmembrane proteins consisting of a lectin-like domain, an epidermal growth factor-like domain, and a variable number of domains that are homologous to complement regulatory proteins. They are important cell adhesion molecules which help LEUKOCYTES attach to VASCULAR ENDOTHELIUM.
A sub-family of RHO GTP-BINDING PROTEINS that is involved in regulating the organization of cytoskeletal filaments. This enzyme was formerly listed as EC
Immunoglobulin molecules having a specific amino acid sequence by virtue of which they interact only with the ANTIGEN (or a very similar shape) that induced their synthesis in cells of the lymphoid series (especially PLASMA CELLS).
The property of blood capillary ENDOTHELIUM that allows for the selective exchange of substances between the blood and surrounding tissues and through membranous barriers such as the BLOOD-AIR BARRIER; BLOOD-AQUEOUS BARRIER; BLOOD-BRAIN BARRIER; BLOOD-NERVE BARRIER; BLOOD-RETINAL BARRIER; and BLOOD-TESTIS BARRIER. Small lipid-soluble molecules such as carbon dioxide and oxygen move freely by diffusion. Water and water-soluble molecules cannot pass through the endothelial walls and are dependent on microscopic pores. These pores show narrow areas (TIGHT JUNCTIONS) which may limit large molecule movement.
Protein of the annexin family exhibiting lipid interaction and steroid-inducibility.
An unsaturated, essential fatty acid. It is found in animal and human fat as well as in the liver, brain, and glandular organs, and is a constituent of animal phosphatides. It is formed by the synthesis from dietary linoleic acid and is a precursor in the biosynthesis of prostaglandins, thromboxanes, and leukotrienes.
The soft tissue filling the cavities of bones. Bone marrow exists in two types, yellow and red. Yellow marrow is found in the large cavities of large bones and consists mostly of fat cells and a few primitive blood cells. Red marrow is a hematopoietic tissue and is the site of production of erythrocytes and granular leukocytes. Bone marrow is made up of a framework of connective tissue containing branching fibers with the frame being filled with marrow cells.
A transient increase in the number of leukocytes in a body fluid.
A phosphatidylinositol 3-kinase subclass that includes enzymes formed through the association of a p110gamma catalytic subunit and one of the three regulatory subunits of 84, 87, and 101 kDa in size. This subclass of enzymes is a downstream target of G PROTEIN-COUPLED RECEPTORS.
The minute vessels that collect blood from the capillary plexuses and join together to form veins.
Material coughed up from the lungs and expectorated via the mouth. It contains MUCUS, cellular debris, and microorganisms. It may also contain blood or pus.
The cells found in the body fluid circulating throughout the CARDIOVASCULAR SYSTEM.
White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each), or NATURAL KILLER CELLS.
Toxins closely associated with the living cytoplasm or cell wall of certain microorganisms, which do not readily diffuse into the culture medium, but are released upon lysis of the cells.
Peptides composed of between two and twelve amino acids.
The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Abnormal fluid accumulation in TISSUES or body cavities. Most cases of edema are present under the SKIN in SUBCUTANEOUS TISSUE.
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
Inflammation of any one of the blood vessels, including the ARTERIES; VEINS; and rest of the vasculature system in the body.
Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.
One of the virulence factors produced by BORDETELLA PERTUSSIS. It is a multimeric protein composed of five subunits S1 - S5. S1 contains mono ADPribose transferase activity.
Disease having a short and relatively severe course.
Any of several ways in which living cells of an organism communicate with one another, whether by direct contact between cells or by means of chemical signals carried by neurotransmitter substances, hormones, and cyclic AMP.
Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.
A mitogen-activated protein kinase subfamily that regulates a variety of cellular processes including CELL GROWTH PROCESSES; CELL DIFFERENTIATION; APOPTOSIS; and cellular responses to INFLAMMATION. The P38 MAP kinases are regulated by CYTOKINE RECEPTORS and can be activated in response to bacterial pathogens.
Damage to any compartment of the lung caused by physical, chemical, or biological agents which characteristically elicit inflammatory reaction. These inflammatory reactions can either be acute and dominated by NEUTROPHILS, or chronic and dominated by LYMPHOCYTES and MACROPHAGES.
An serine-threonine protein kinase that requires the presence of physiological concentrations of CALCIUM and membrane PHOSPHOLIPIDS. The additional presence of DIACYLGLYCEROLS markedly increases its sensitivity to both calcium and phospholipids. The sensitivity of the enzyme can also be increased by PHORBOL ESTERS and it is believed that protein kinase C is the receptor protein of tumor-promoting phorbol esters.
Washing out of the lungs with saline or mucolytic agents for diagnostic or therapeutic purposes. It is very useful in the diagnosis of diffuse pulmonary infiltrates in immunosuppressed patients.
A platelet-specific protein which is released when platelets aggregate. Elevated plasma levels have been reported after deep venous thrombosis, pre-eclampsia, myocardial infarction with mural thrombosis, and myeloproliferative disorders. Measurement of beta-thromboglobulin in biological fluids by radioimmunoassay is used for the diagnosis and assessment of progress of thromboembolic disorders.
A basic enzyme that is present in saliva, tears, egg white, and many animal fluids. It functions as an antibacterial agent. The enzyme catalyzes the hydrolysis of 1,4-beta-linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrin. EC
A cytokine that stimulates the growth and differentiation of B-LYMPHOCYTES and is also a growth factor for HYBRIDOMAS and plasmacytomas. It is produced by many different cells including T-LYMPHOCYTES; MONOCYTES; and FIBROBLASTS.
The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria normally commensal in the flora of CATTLE and SHEEP. But under conditions of physical or PHYSIOLOGICAL STRESS, it can cause MASTITIS in sheep and SHIPPING FEVER or ENZOOTIC CALF PNEUMONIA in cattle. Its former name was Pasteurella haemolytica.
Established cell cultures that have the potential to propagate indefinitely.
An endopeptidase that is structurally similar to MATRIX METALLOPROTEINASE 2. It degrades GELATIN types I and V; COLLAGEN TYPE IV; and COLLAGEN TYPE V.
Cellular release of material within membrane-limited vesicles by fusion of the vesicles with the CELL MEMBRANE.
A multisystemic disease of a complex genetic background. It is characterized by inflammation of the blood vessels (VASCULITIS) leading to damage in any number of organs. The common features include granulomatous inflammation of the RESPIRATORY TRACT and kidneys. Most patients have measurable autoantibodies (ANTINEUTROPHIL CYTOPLASMIC ANTIBODIES) against neutrophil proteinase-3 (WEGENER AUTOANTIGEN).
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
A derivative of complement C5a, generated when the carboxy-terminal ARGININE is removed by CARBOXYPEPTIDASE B present in normal human serum. C5a des-Arg shows complete loss of spasmogenic activity though it retains some chemotactic ability (CHEMOATTRACTANTS).
Measurable and quantifiable biological parameters (e.g., specific enzyme concentration, specific hormone concentration, specific gene phenotype distribution in a population, presence of biological substances) which serve as indices for health- and physiology-related assessments, such as disease risk, psychiatric disorders, environmental exposure and its effects, disease diagnosis, metabolic processes, substance abuse, pregnancy, cell line development, epidemiologic studies, etc.
A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.

GM-CSF-deficient mice are susceptible to pulmonary group B streptococcal infection. (1/19639)

Granulocyte-macrophage colony-stimulating factor (GM-CSF) gene-targeted mice (GM-/-) cleared group B streptococcus (GBS) from the lungs more slowly than wild-type mice. Expression of GM-CSF in the respiratory epithelium of GM-/- mice improved bacterial clearance to levels greater than that in wild-type GM+/+ mice. Acute aerosolization of GM-CSF to GM+/+ mice significantly enhanced clearance of GBS at 24 hours. GBS infection was associated with increased neutrophilic infiltration in lungs of GM-/- mice, while macrophage infiltrates predominated in wild-type mice, suggesting an abnormality in macrophage clearance of bacteria in the absence of GM-CSF. While phagocytosis of GBS was unaltered, production of superoxide radicals and hydrogen peroxide was markedly deficient in macrophages from GM-/- mice. Lipid peroxidation, assessed by measuring the isoprostane 8-iso-PGF2alpha, was decreased in the lungs of GM-/- mice. GM-CSF plays an important role in GBS clearance in vivo, mediated in part by its role in enhancing superoxide and hydrogen peroxide production and bacterial killing by alveolar macrophages.  (+info)

Interaction of inflammatory cells and oral microorganisms. II. Modulation of rabbit polymorphonuclear leukocyte hydrolase release by polysaccharides in response to Streptococcus mutans and Streptococcus sanguis. (2/19639)

The release of lysosomal hydrolases from polymorphonuclear leukocytes (PMNs) has been postulated in the pathogenesis of tissue injury in periodontal disease. In the present study, lysosomal enzyme release was monitored from rabbit peritoneal exudate PMNs exposed to Streptocccus mutans or Streptococcus sanguis. S. mutans grown in brain heart infusion (BHI) broth failed to promote significant PMN enzyme release. S. sanguis grown in BHI broth, although more effective than S. mutants, was a weak stimulus for promotion of PMN hydrolase release. Preincubation of washed, viable S. mutans in sucrose or in different-molecular-weight dextrans resulted in the ability of the organisms to provoke PMN release reactions. This effect could bot be demonstrated with boiled or trypsinized S. mutans or with viable S. sanguis. However, when grown in BHI broth supplemented with sucrose, but not with glucose, both S. mutans and S. sanguis triggered discharge of PMN enzymes. The mechanism(s) whereby dextran or sucrose modulates PMN-bacterial interaction may in some manner be related to promotion of microbial adhesiveness or aggregation by dextran and by bacterial synthesis of glucans from sucrose.  (+info)

Interaction of inflammatory cells and oral microorganisms. III. Modulation of rabbit polymorphonuclear leukocyte hydrolase release response to Actinomyces viscosus and Streptococcus mutans by immunoglobulins and complement. (3/19639)

In the absence of antiserum, rabbit polymorphonuclear leukocytes (PMNs) released lysosomal enzymes in response to Actinomyces viscosus (19246) but not to Streptococcus mutans (6715). Antibodies had a marked modulating influence on these reactions. PMN hydrolase release was significantly enhanced to both organisms when specific rabbit antiserum and isolated immunoglobulin G (IgG) were included in the incubations. Immune complex F(ab')2 fragments of IgG directed against S. mutans agglutinated bacteria. Immune complexes consisting of S. mutans and F(ab')2 fragments of IgG directed against this organism were not effective as bacteria-IgG complexes in stimulating PMN release. The intensity of the release response to bacteria-IgG complexes was also diminished when PMNs were preincubated with isolated Fc fragments derived from IgG. Fresh serum as a source of complement components had no demonstrable effect on PMN release either alone or in conjuction with antiserum in these experiments. These data may be relevant to the mechanisms and consequences of the interaction of PMNs and plaque bacteria in the pathogenesis of periodontal disease.  (+info)

Lung weight parallels disease severity in experimental coccidioidomycosis. (4/19639)

Evidence provided by histopathological study of lesions is a valuable adjunct for evaluating chemotherapeutic efficacy in experimental animal models, In addition, this should be correlated with a measure of disease severity in the same animal. The latter could be obtained by homogenization of infected organs and quantitative enumeration of viable cells of the etiological agent, but this would preclude histopathological studies in the same animal. Progression of disease in pulmonary infection is associated with replacement of air space by fluid, cells, and cellular debris. Therefore, an increase in lung weight should reflect severity of disease. Results with the murine model of coccidioidomycosis demonstrate that increasing lung weight parallels the increasing census of fungus cells in the lungs of both treated and nontreated infected mice. This was supported with evidence obtained from microscopic studies of lesions indicating that specific chemotherapy limited spread of the infection and inhibited multiplication of the fungus in the lung. Therefore, lung weight can be used as a measure of disease severity in the murine model of coccidioidomycosis.  (+info)

Enhanced Th1 activity and development of chronic enterocolitis in mice devoid of Stat3 in macrophages and neutrophils. (5/19639)

We have generated mice with a cell type-specific disruption of the Stat3 gene in macrophages and neutrophils. The mutant mice are highly susceptible to endotoxin shock with increased production of inflammatory cytokines such as TNF alpha, IL-1, IFN gamma, and IL-6. Endotoxin-induced production of inflammatory cytokines is augmented because the suppressive effects of IL-10 on inflammatory cytokine production from macrophages and neutrophils are completely abolished. The mice show a polarized immune response toward the Th1 type and develop chronic enterocolitis with age. Taken together, Stat3 plays a critical role in deactivation of macrophages and neutrophils mainly exerted by IL-10.  (+info)

Characterization and partial purification of a novel neutrophil membrane-associated kinase capable of phosphorylating the respiratory burst component p47phox. (6/19639)

The phosphorylation of p47phox is widely viewed as an important step in the activation of the neutrophil respiratory burst oxidase system. The exact nature of the kinase(s) responsible remains to be elucidated. We show here that such a kinase was detected on neutrophil membranes activated by either PMA or formyl-methionyl-leucyl-phenylalanine. This enzyme is not intrinsic to the neutrophil membrane and could be eluted with 0.5 M NaCl. The kinase activity was partially purified and was found not to be due to the presence of previously suggested kinases, including protein kinase C isotypes, mitogen-activated protein kinase and protein kinase B. Gel filtration and renaturation in substrate gels suggest a molecular mass of between 45 and 51 kDa. The kinase activity was independent of calcium and lipids but was potently inhibited by staurosporine. Treatment with protein phosphatase 2Ac suggested that the kinase was activated by serine/threonine phosphorylation. Phosphopeptide maps indicated that the kinase phosphorylated p47phox on similar sites to those found in vivo. These results indicate that activation of neutrophils by PMA results in the activation of a membrane-associated kinase that may play a part in the regulation of neutrophil NADPH oxidase through its ability to phosphorylate p47phox.  (+info)

Non-serum-dependent chemotactic factors produced by Candida albicans stimulate chemotaxis by binding to the formyl peptide receptor on neutrophils and to an unknown receptor on macrophages. (7/19639)

Serum-free culture filtrates of six Candida species and Saccharomyces cerevisiae were found to contain chemoattractants for human polymorphonuclear leukocytes (PMNs) and a mouse macrophage-like cell line, J774. The chemotactic factors differed for the PMN and J774 cells, however, in terms of heat stability, kinetics of liberation by the yeast cells, and divalent cation requirements for production. The chemoattractant in Candida albicans culture filtrates appeared to act through the formyl peptide receptor (FPR) of PMNs, since it was found to induce chemotaxis of Chinese hamster ovary (CHO) cells that were expressing the human FPR but did not induce chemotaxis of wild-type CHO cells. The C. albicans culture filtrates also induced migration of PMNs across confluent monolayers of a human gastrointestinal epithelial cell line, T84; migration occurred in the basolateral-to-apical direction but not the reverse direction, unless the epithelial tight junctions were disrupted. J774 cells did not migrate toward the formylated peptide (fMet-Leu-Phe; fMLF), and chemotaxis toward the C. albicans culture filtrate was not inhibited by an FPR antagonist (t-butoxycarbonyl-Met-Leu-Phe), suggesting that a different receptor mediated J774 cell chemotaxis. In conclusion, we have identified a receptor by which a non-serum-dependent chemotactic factor (NSCF) produced by C. albicans induced chemotaxis of PMNs. Additionally, we have shown that NSCF was active across epithelial monolayers. These findings suggest that NSCFs produced by C. albicans and other yeast species may influence host-pathogen interactions at the gastrointestinal tract mucosal surface by inducing phagocytic-cell infiltration.  (+info)

Role of the extracellular signal-regulated protein kinase cascade in human neutrophil killing of Staphylococcus aureus and Candida albicans and in migration. (8/19639)

Killing of Staphylococcus aureus and Candida albicans by neutrophils involves adherence of the microorganisms, phagocytosis, and a collaborative action of oxygen reactive species and components of the granules. While a number of intracellular signalling pathways have been proposed to regulate neutrophil responses, the extent to which each pathway contributes to the killing of S. aureus and C. albicans has not been clearly defined. We have therefore examined the effect of blocking one such pathway, the extracellular signal-regulated protein kinase (ERK) cascade, using the specific inhibitor of the mitogen-activated protein kinase/ERK kinase, PD98059, on the ability of human neutrophils to kill S. aureus and C. albicans. Our data demonstrate the presence of ERK2 and a 43-kDa form of ERK but not ERK1 in human neutrophils. Upon stimulation with formyl methionyl leucyl phenylalanine (fMLP), the activities of both ERK2 and the 43-kDa form were stimulated. Despite abrogating the activity of both ERK forms, PD98059 only slightly reduced the ability of neutrophils to kill S. aureus or C. albicans. This is consistent with our finding that PD98059 had no effect on neutrophil adherence or degranulation, although pretreatment of neutrophils with PD98059 inhibited fMLP-stimulated superoxide production by 50%, suggesting that a change in superoxide production per se is not strictly correlated with microbicidal activity. However, fMLP-stimulated chemokinesis was markedly inhibited, while random migration and fMLP-stimulated chemotaxis were partially inhibited, by PD98059. These data demonstrate, for the first time, that the ERK cascade plays only a minor role in the microbicidal activity of neutrophils and that the ERK cascade is involved primarily in regulating neutrophil migration in response to fMLP.  (+info)

The formation of neutrophil extracellular traps induced by antineutrophil cytoplasmic autoantibodies has been implicated in the pathogenesis of antineutrophil cytoplasmic autoantibody-associated vasculitis. Kraaij et al. now provide evidence that excessive neutrophil extracellular trap formation in vitro induced by sera from patients with antineutrophil cytoplasmic autoantibody-associated vasculitis is associated with active disease but is not dependent on the presence of antineutrophil cytoplasmic autoantibodies. ...
Neutrophil cell trapping bacteria. Coloured scanning electron micrograph (SEM) of bacteria (rod-shaped) being trapped by a neutrophil cell. The neutrophil cell (a type of white blood cell) has trapped the bacteria with extruded material that forms a net-like structure called a NET (neutrophil extracellular trap). This method of cellular defence was first discovered in 2004. These are Shigella sp. bacteria, one of the causes of dysentery, a severe intestinal inflammation. - Stock Image P276/0186
Staphylococcus aureus is a commensal organism in approximately 30% of the human population and colonization is a significant risk factor for invasive infection. As a result of this, there is a great need to better understand how S. aureus overcomes human immunity. Neutrophils are essential during the innate immune response to S. aureus, yet this microorganism uses multiple evasion strategies to avoid killing by these immune cells, perhaps the most catastrophic of which is the rapid induction of neutrophil cell death. The aim of this study was to better understand the mechanisms underpinning S. aureus-induced neutrophil lysis, and how this contributes to pathogenesis in a whole organism model of infection. To do this we screened the genome-wide Nebraska Transposon Mutant Library (NTML) in the community acquired methicillin resistant S. aureus strain, USA300, for decreased ability to induce neutrophil cell lysis. Out of 1,920 S. aureus mutants, a number of known regulators of cell lysis ...
Optic atrophy 1 (OPA1) is a mitochondrial inner membrane protein that has an important role in mitochondrial fusion and structural integrity. Dysfunctional OPA1 mutations cause atrophy of the optic nerve leading to blindness. Here, we show that OPA1 has an important role in the innate immune system. Using conditional knockout mice lacking Opa1 in neutrophils (Opa1N∆), we report that lack of OPA1 reduces the activity of mitochondrial electron transport complex I in neutrophils. This then causes a decline in adenosine-triphosphate (ATP) production through glycolysis due to lowered NAD+ availability. Additionally, we show that OPA1-dependent ATP production in these cells is required for microtubule network assembly and for the formation of neutrophil extracellular traps. Finally, we show that Opa1N∆ mice exhibit a reduced antibacterial defense capability against Pseudomonas aeruginosa. Optic atrophy 1 (OPA1) is known to be important for mitochondrial fusion and structural integrity. Here, using OPA1
Bacteria colony counts in peripheral blood and in bronchoalveolar lavage fluid (BALF) were also markedly decreased in PLD2−/− mice versus WT (Fig. 3 a). Bacteria released into the peritoneal cavity eventually make their way through the circulation and enter lung tissue, resulting in lung inflammation (Matute-Bello et al., 2001). Bacteria colony counts in lung tissues were also significantly decreased in PLD2−/− mice versus WT (Fig. 3 a). Live bacterial colony numbers were significantly increased in liver and spleen 24 h after CLP in WT mice compared with PLD2−/− mice (Fig. 3 a).. It was recently reported that neutrophils generate NETs to trap and kill invading bacteria (Brinkmann et al., 2004). To investigate the effect of PLD2 deficiency on NET formation, we stained neutrophils with SYTOX Green nucleic acid stain, a nonpermeable dye that stains nucleic acid, a primary component of NETs. Stimulation of neutrophils isolated from WT mice with ionomycin induced NET formation (Fig. 3 d). ...
Definition of neutrophil microbicidal assay in the Legal Dictionary - by Free online English dictionary and encyclopedia. What is neutrophil microbicidal assay? Meaning of neutrophil microbicidal assay as a legal term. What does neutrophil microbicidal assay mean in law?
Polymorphonuclear neutrophils, or granulocytes, are essential effector cells of the innate immune system against bacterial infections. Their role in sepsis has been long established as the primary phagocyte to clear the infectious process. In the early phase of sepsis, one observes a massive recruitment of immature neutrophils from the bone marrow into peripheral blood, the so-called band forms or left shift cells. Despite the daily clinical use of neutrophil band forms count in the care of septic patients and their abundance in septic blood, no information exists on the fate of these cells, nor on their capacity to mount an efficient innate immune response. It is the goal of this proposal to study the fate and the innate immune functions of immature neutrophils obtained in patients with early septic shock. Immature neutrophils will be separated from mature neutrophils. The following functions will be studied ex vivo in mature vs. immature neutrophils from a series of patients with severe ...
TY - JOUR. T1 - Role of arachidonyl triglycerides within lipid bodies in eicosanoid formation by human polymorphonuclear cells. AU - Johnson, Margaret M.. AU - Vaughn, Benjamin. AU - Triggiani, Massimo. AU - Swan, Dennis D.. AU - Fonteh, Alfred N.. AU - Chilton, Floyd H.. PY - 1999/1/1. Y1 - 1999/1/1. N2 - Increasing evidence suggests that the subcellular and glycerolipid localization of esterified arachidonic acid (AA) is a key factor in regulating its availability to lipases. The goal of the current study was to determine the potential of AA stored in triglycerides (TG) to serve as a substrate for lipases and 5-lipoxygenase during neutrophil (polymorphonuclear leukocytes, PMN) activation. PMN containing high concentrations of AA in TG were generated by culturing PMN in vitro with high concentrations of exogenous AA (eAA) for 12 h. Cellular AA increased 2- and 4-fold in PMNs incubated with 5 and 20 μM AA, respectively, and this increase was almost exclusively observed in neutral lipids (NL). ...
The mechanism of Ca2+ entry after ligand binding to receptors on the surface of non-excitable cells is a current focus of interest. Considerable attention has been given to Ca2+ influx induced by emptying of intracellular pools. Thapsigargin, an inhibitor of microsomal Ca(2+)-ATPase, is an important tool in inducing store-regulated Ca2+ influx. In the present paper we show that, at concentrations above 500 nM, thapsigargin also has an opposite effect: it inhibits store-regulated Ca2+ influx into Fura-2-loaded human neutrophil granulocytes. As thapsigargin has been frequently applied at concentrations up to 2 microM, its inhibitory action on plasma-membrane Ca2+ fluxes deserves consideration. ...
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The chemokinetic inhibitory factor (CIF) is a recently described B-cell derived lymphokine that mediates a chemokinetic inhibitory effect on human polymorphonuclear leukocyte (PMN) migration. In the present report the interaction of CIF with the neutrophil plasma membrane was studied. Normal human peripheral blood neutrophils and purified neutrophil plasma membranes selectively removed biologic activity from CIF-containing concentrates obtained during the purification procedure from conditioned medium. Removal was obtained at both 4 degrees C and 37 degrees C. Furthermore, HL-60 cells treated with dimethyl sulfoxide removed CIF activity (granulocyte-like cells) but HL-60 cells treated with 12-O-tetradecanoylphorbol-13-acetate (macrophage-like cells) did not. Purified human blood monocytes, cells from the macrophage-like U-937 cell line and cells from the basophilic leukemia cell line KU-812 did not remove CIF. These studies suggest that neutrophils express specific binding sites for ...
To gain further insight into the effects of calcium influx on neutrophil chemotaxis, we depleted the calcium in the under-agarose chemotaxis models using a calcium-free solution and EGTA. We observed that the inhibitory effects of LPS on neutrophil chemotaxis were impaired in the presence of calcium-depleted medium (Fig. 3C). Moreover, using a calcium ionophore ionomycin to stimulate neutrophils, a sustained calcium influx was observed and chemoattractant-induced neutrophil chemotaxis was dramatically inhibited (SI Appendix, Fig. S7A). The sustained calcium influx appeared to be required for initiating stop signal of neutrophil chemotaxis. Previous reports displayed that intracellular calcium was necessary for neutrophil migration (19). Therefore, we further clarified the effects of calcium on neutrophil migration. Different chemoattractant-induced calcium mobilization patterns were found to be inconsistent (20, 21). We noted that different from stimulation of IL-8, a rapid increase in ...
Neutrophil extracellular traps (NETs) play an important role in innate immunity to microbial infections. NETs have been described in several species, but the molecular details of NET formation and their role in infection has not been addressed, partly because we lack optimal experimental models. Here we describe tools to investigate NET formation in neutrophils isolated from mice. Upon in vitro stimulation of wild-type mouse neutrophils with PMA, we analyzed 3 important steps in the process of NET formation: reactive oxygen species (ROS) production, NET cell death and NET release. As expected, neutrophils from NADPH oxidase-deficient mice failed to produce ROS and did not die nor release NETs upon stimulation. We found that neutrophils from several mouse strains produced NETs with different efficiency and that NET formation correlated with the amount of ROS produced. Activation with Candida albicans also resulted in ROS production and NET cell death. The hyphal form of this fungus induced NETs ...
JS Parmar, D Bilton, ER Chilvers, DA Lomas; The Selective Chemotactic Effect of α1-Antitrypsin Polymers for Human Peripheral Blood Neutrophils. Clin Sci (Lond) 1 July 2002; 103 (s47): 56P. doi: Download citation file:. ...
Our results uncovered an unexpected role for MPO to influence the fate of neutrophils and consequently the duration of inflammation. By suppressing the constitutive cell death program, MPO prolonged the life span of neutrophils, thereby delaying the resolution of inflammation. These actions were specific for MPO, because other azurophilic granule constituents lactoferrin and elastase failed to affect neutrophil apoptosis.. Consistent with the commitment of neutrophils to apoptosis, MPO at clinically relevant concentrations delayed, rather than blocked apoptosis, resulting in prolonged survival of human neutrophils in vitro. We confirmed that increasing plasma concentrations of MPO in rats to levels comparable to those detected in patients with inflammatory vascular diseases20,21 was sufficient to retard the apoptotic machinery in neutrophils as assayed ex vivo. Furthermore, MPO also suppressed apoptosis in neutrophils that had emigrated into the airways and delayed resolution of inflammation in ...
TY - JOUR. T1 - Plasminogen activator inhibitor-1 supports IL-8-mediated neutrophil transendothelial migration by inhibition of the constitutive shedding of endothelial IL-8/heparan sulfate/syndecan-1 complexes. AU - Marshall, Lindsay J.. AU - Ramdin, Lara S.P.. AU - Brooks, Teresa. AU - Charlton, Peter. AU - Shute, Janis K.. PY - 2003/8/15. Y1 - 2003/8/15. N2 - The endothelium is the primary barrier to leukocyte recruitment at sites of inflammation. Neutrophil recruitment is directed by transendothelial gradients of IL-8 that, in vivo, are bound to the endothelial cell surface. We have investigated the identity and function of the binding site(s) in an in vitro model of neutrophil transendothelial migration. In endothelial culture supernatants, IL-8 was detected in a trimolecular complex with heparan sulfate and syndecan-1. Constitutive shedding of IL-8 in this form was increased in the presence of a neutralizing Ab to plasminogen activator inhibitor-1 (PAI-1), indicating a role for endothelial ...
TY - JOUR. T1 - Organism-Specific Neutrophil-Endothelial Cell Interactions in Response to Escherichia coli, Streptococcus pneumoniae, and Staphylococcus aureus. AU - Moreland, Jessica G.. AU - Bailey, Gail. AU - Nauseef, William M.. AU - Weiss, Jerrold P.. PY - 2004/1/1. Y1 - 2004/1/1. N2 - The recruitment of polymorphonuclear leukocytes (PMNs) from the vascular space into the lung interstitium and airspace is an early step in the host innate immune response to bacterial invasion of these sites. To determine the ability of intact bacteria to directly elicit PMN migration across an endothelial monolayer, we studied in vitro migration of PMNs across a monolayer of human pulmonary microvascular endothelial cells in response to Streptococcus pneumoniae, Staphylococcus aureus, and Escherichia coli, as well as to purified E. coli LPS. Bacterial induction of PMN migration was dose dependent and elicited by ≥104 bacteria/ml of each of the species tested. Pretreatment of PMNs with blocking Abs to CD18 ...
Neutrophil superoxide anion production was measured in healthy subjects and in patients with quiescent and active Crohns disease using superoxide dismutase inhibitable cytochrome C reduction. Three stimuli were used: phorbol 12-myristate 13-acetate (PMA1), phorbol 20-oxo-20-deoxy 12-myristate 13-acetate (PMA2), and Candida albicans in serum. Normal neutrophils produced significantly more superoxide anion than Crohns disease neutrophils with both PMA1 (mean (SD) 9.6 (2.2) v 8.6 (1.8) nmol/10(6) cells/5 minutes, p = 0.04) and PMA2 (1.8 (0.8) v 0.8 (0.77) nmol/10(6) cells/5 minutes, p = 0.00004). With C albicans in serum, normal and Crohns disease neutrophils produced similar amounts of superoxide anion (4.4 (1.5) v 4.3 (1.7) nmol/10(6) cells/30 minutes, not significant). Results were independent of disease activity. Superoxide anion production by PMA-stimulated Crohns disease neutrophils is significantly lower than by normal neutrophils.. ...
Human granulocyte-macrophage colony-stimulating factor (GM-CSF) modulates the function of mature neutrophils by priming for enhanced chemotaxis and oxidative metabolism in response to N-formyl-methionyl-leucyl-phenylalanine (f-Met-Leu-Phe). Our studies establish a relationship between f-Met-Leu-Phe receptor number and affinity and neutrophil chemotaxis and oxidative metabolism. A brief (5- to 15-min) exposure to physiologic concentrations of GM-CSF (10 pM to 100 pM) enhances f-Met-Leu-Phe-induced neutrophil chemotaxis by 85%, correlating with a rapid threefold increase (46,000/cell to 150,000/cell) in high-affinity neutrophil f-Met-Leu-Phe receptors. More prolonged incubation (1 to 2 hr) of neutrophils with GM-CSF is accompanied by a change to low-affinity f-Met-Leu-Phe receptors (Kd = 29 nM to Kd = 99 nM) concomitant with priming for enhanced neutrophil oxidative metabolism. Moreover, enhanced chemotactic responses to f-Met-Leu-Phe are no longer evident after more prolonged incubation of ...
TY - JOUR. T1 - Neutrophil extracellular traps in autoimmune diseases. T2 - Trampas extracelulares de neutrófilos en enfermedades autoinmunes. AU - Monsalve, Diana M.. AU - Acosta-Ampudia, Yeny. AU - Ramírez-Santana, Carolina. AU - Polo, José Fernando. AU - Anaya, Juan Manuel. PY - 2020/10/1. Y1 - 2020/10/1. N2 - Neutrophils play an important role in immune defence against several pathogens. These cells actively participate in the innate immune response through different functions, such as chemotaxis, phagocytosis, oxidative burst and degranulation, which have been widely studied. However, in the last few years, a new function has been described; activated neutrophils are able to release web-like chromatin structures known as neutrophil extracellular traps (NETs). These structures formed by DNA, histones, and proteins, immobilize and kill microorganisms. Disruption in NET formation is associated with the pathophysiology of several disorders, including the autoimmune diseases. NETs are an ...
IL-8 is a potent neutrophil chemoattractant that has been detected in high concentrations at acutely inflamed sites in vivo. Many cell types, including peripheral blood neutrophils, produce IL-8 that can be released by a variety of pro-inflammatory stimuli. However, the functional importance of neutrophil IL-8 during exudation is not yet known. We now report that neutrophils, harvested from skin lesions on the forearms of normal human volunteers (exudative neutrophils), expressed 100-fold higher levels of cell-associated IL-8 and spontaneously released up to 50-fold more IL-8 than freshly isolated peripheral blood neutrophils from the same donor. Furthermore, cell-associated IL-8 in peripheral blood neutrophils increased 20-fold during incubation at 37 degrees C in vitro and was increased over 200-fold after treatment with the Ca2+ ionophore A23187. More than 35% of the cell-associated IL-8 could be released by stimulation with either Ca2+ ionophore A23187 or phorbol myristate acetate. IL-8 was ...
Introduction: Hormonal and metabolic changes, as well as energy imbalance, can affect health, production and reproductive performance of dairy cows. In the present study, we evaluated phagocytosis and respiratory burst neutrophil activity during the transition period and early lactation and compared it with biochemical and hematological parameters in dairy cows. Methodology: Simmental cows (n = 21) were enrolled in the study. Whole blood samples were collected weekly from 3 weeks pre- calving until 6 weeks post calving. Basic metabolic and blood parameters were assessed by routine laboratory analyses, while neutrophil functions were analyzed by commercial test kits. Results: Optimal neutrophil response was observed pre and post calving. The highest value was recorded in the 6th week after calving (89.54 ± 7.61%) and being significantly higher (p , 0.01) as compared to values recorded at two and one week before and one week after calving. The percentage of activated neutrophils was high during ...
In a previous study we observed that neutrophils respond with a rapid rise in [Ca2+]i during adherence to cytokine-activated endothelial cells (EC), caused by EC membrane-associated platelet-activating factor (PAF). In the present study, we investigated whether this form of PAF was important in neutrophil adherence and migration across monolayers of rIL-1 beta- or rTNF alpha-prestimulated EC. PAF receptor antagonists prevented neutrophil migration across cytokine-pretreated EC by approximately 60% (P less than 0.005) without interfering with the process of adherence. The antagonists WEB 2086 and L-652,731 had no effect on neutrophil migration across resting EC induced by formylmethionyl-leucyl-phenylalanine (FMLP). A murine anti-IL-8 antiserum was found to also partially inhibit the neutrophil transmigration across cytokine-activated EC. When the anti-IL-8 antiserum was used in combination with a PAF receptor antagonist, neutrophil migration across cytokine-pretreated monolayers of EC was ...
Inhibition of LPS induced sputum neutrophil percentage. The reduction in sputum neutrophil percentage caused by active treatments compared to placebo are shown;
TY - JOUR. T1 - Nitrite generation and antioxidant effects during neutrophil apoptosis. AU - Misso, Neil L.A.. AU - Peacock, Craig D.. AU - Neil Watkins, D.. AU - Thompson, Philip J.. PY - 2000/3/15. Y1 - 2000/3/15. N2 - Neutrophil apoptosis is important for the resolution of airway inflammation in a number of lung diseases. Inflammatory mediators, endogenous reactive oxygen and nitrogen species, and intracellular and extracellular antioxidants may all influence neutrophil apoptosis. This study investigated the involvement of these factors during apoptosis of neutrophils cultured in vitro. Neutrophils undergoing spontaneous apoptosis in culture as assessed by annexin V binding generated significant amounts of nitrite. Incubation with agonistic anti-Fas monoclonal antibody or tumor necrosis factor-α (TNF-α) enhanced neutrophil apoptosis at 6 h, although it decreased nitrite accumulation. Although granulocyte-macrophage colony-stimulating factor significantly reduced neutrophil apoptosis, this ...
We introduce machine learning (ML) to perform classification and quantitation of images of nuclei from human blood neutrophils. Here we assessed the use of convolutional neural networks (CNNs) using free, open source software to accurately quantitate neutrophil NETosis, a recently discovered process involved in multiple human diseases. CNNs achieved ,94% in performance accuracy in differentiating NETotic from non-NETotic cells and vastly facilitated dose-response analysis and screening of the NETotic response in neutrophils from patients. Using only features learned from nuclear morphology, CNNs can distinguish between NETosis and necrosis and between distinct NETosis signaling pathways, making them a precise tool for NETosis detection. Furthermore, by using CNNs and tools to determine object dispersion, we uncovered differences in NETotic nuclei clustering between major NETosis pathways that is useful in understanding NETosis signaling events. Our study also shows that neutrophils from patients ...
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This study shows that in mice selectively depleted of neutrophils by treatment with a monoclonal antibody, RB6-8C5, listeriosis is severely exacerbated in the liver, but not in the spleen or peritoneal cavity during the crucial first day of infection. At sites of infection in the livers of neutrophil-depleted mice, Listeria monocytogenes grew to large numbers inside hepatocytes. By contrast, in the livers of normal mice neutrophils rapidly accumulated at infectious foci and this was associated with the lysis of infected hepatocytes that served to abort infection in these permissive cells. In the spleen the situation was different, in that depletion of neutrophils did not result in appreciable exacerbation of infection. In this organ intact infected cells, many of which appeared to be fibroblast-like stromal cells, were found at foci of infection in the presence or absence of large numbers of neutrophils. This suggests that neutrophils are less effective at destroying L. monocytogenes-infected ...
Neutrophil extracellular traps (NETs) are networks of extracellular fibers, primarily composed of DNA from neutrophils, which bind pathogens. Neutrophils are the immune systems first-line of defense against infection and have conventionally been thought to kill invading pathogens through two strategies: engulfment of microbes and secretion of anti-microbials. In 2004, a novel third function was identified: formation of NETs. NETs allow neutrophils to kill extracellular pathogens while minimizing damage to the host cells. Upon in vitro activation with the pharmacological agent phorbol myristate acetate (PMA), Interleukin 8 (IL-8) or lipopolysaccharide (LPS), neutrophils release granule proteins and chromatin to form an extracellular fibril matrix known as NETs through an active process. High-resolution scanning electron microscopy has shown that NETs consist of stretches of DNA and globular protein domains with diameters of 15-17 nm and 25 nm, respectively. These aggregate into larger threads ...
Neutrophil granulocytes: Low neutrophil (neutropenia) and high neutrophil level counts on blood tests: Easy to understand entry on this type of white blood cell (Lymphocytes B cells and T cells; Monocytes; Eosinophils; Basophils).
Early and accurate risk assessment is an important clinical demand in patients with infective endocarditis (IE). The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are independent predictors of prognosis in many infectious and cardiovascular diseases. Very limited studies have been conducted to evaluate the prognostic role of these markers in IE. We analyzed clinical, laboratory, and echocardiographic data and outcomes throughout the whole period of hospitalization for a total of 142 consecutive patients with definitive IE. The overall in-hospital mortality was 21%. Major complications defined as central nervous system embolization, fulminant sepsis, acute heart failure, acute renal failure, and major artery embolization occurred in 38 (27%), 34 (24%), 32 (22.5%), 40 (28%), and 90 (63.4%) patients, respectively. The NLR, total leucocyte count (TLC), neutrophil percentage, creatinine, and C-reactive protein (CRP) level obtained upon admission were significantly higher in the
TY - JOUR. T1 - Endotoxin-induced selective dysfunction of rabbit polymorphonuclear leukocytes in response to endogenous chemotactic factors. AU - Hartiala, K. T.. AU - Langlois, L.. AU - Goldstein, I. M.. AU - Rosenbaum, J. T.. PY - 1985. Y1 - 1985. N2 - To assess the mechanism and specificity of polymorphonuclear leukocytes (PMN) dysfunction induced by endotoxin, rabbits were injected intravenously with 100 μg of Escherichia coli endotoxin, and PMN function was studied 18 to 24 h later. Compared to PMN from normal rabbits, peripheral blood PMN from rabbits injected with endotoxin showed diminished chemotactic responsiveness to two endogenous peptides, C5a (complement) and platelet-derived growth factor, and to two endogenous lipids, leukotriene B4 and platelet-activating factor. The chemotactic response to the synthetic chemotactic peptide, N-formyl-methionyl-leucyl-phenylalanine (FMLP), was unimpaired. In contrast to migration, endotoxin injection resulted in inhibition of the secretory ...
TY - JOUR. T1 - Rac2 concentrations in umbilical cord neutrophils. AU - Meade, Virginia M.. AU - Barese, Cecilia N.. AU - Kim, Chaekyun. AU - Njinimbam, Charles G.. AU - Marchal, Christophe C.. AU - Ingram, David A.. AU - Clapp, D. Wade. AU - Dinauer, Mary C.. AU - Yoder, Mervin C.. PY - 2006/9/1. Y1 - 2006/9/1. N2 - Background: Human newborn infants display a variety of immunodeficiencies of immaturity, including diminished neutrophil adhesion, chemotaxis, and migration. Rac2, a guanosine triphosphate-binding protein, is an essential regulator of human neutrophil migration and chemotaxis. Since human subjects and mice deficient in Rac2 display deficiencies in neutrophil functions similar to newborn infants, we postulated that newborn neutrophils may be deficient in Rac2. Objectives: The aim of the study was to measure Rac1 and Rac2 concentrations in neutrophils from umbilical cord blood. Methods: Neutrophils from cord and adult blood were isolated, total cell lysates extracted, and Rac protein ...
Depletion of neutrophils following sand fly bite enhances the efficacy of ALM+CpG vaccination.AMC, ALM+CpG vaccinated, or healed mice were exposed to the bites
Cystic fibrosis (CF) lung disease is defined by large numbers of neutrophils and associated damaging products in the airway. Delayed neutrophil apoptosis is described in CF although it is unclear whether this is a primary neutrophil defect or a response to chronic inflammation. Increased levels of neutrophil extracellular traps (NETs) have been measured in CF and we aimed to investigate the causal relationship between these phenomena and their potential to serve as a driver of inflammation. We hypothesised that the delay in apoptosis in CF is a primary defect and preferentially allows CF neutrophils to form NETs, contributing to inflammation ...
In this study, we demonstrated that a modest reduction of neutrophil counts in patients with T1D at onset is accompanied by a marked elevation of protein levels and enzymatic activities of NE and PR3, the two major neutrophil serine proteases. Furthermore, these changes in T1D patients are closely associated with increased neutrophil NETosis, as determined by quantification of MPO-DNA complexes in the circulation. These findings suggest that the reduction of neutrophil counts in T1D patients is partly attributed to augmented NETosis, which in turn leads to increased NET formation and the release of NE and PR3 into the blood stream.. We showed that the amplitude of elevation in circulating NE/PR3 enzymatic activities and NET formation in patients with disease duration of ,1 year is substantially higher than those with disease duration of ,1 year. A significant reduction in neutrophil counts is observed only in T1D patients with a disease duration of ,1 year. Consistent with our findings, a ...
Emerging evidence shows that miRNAs are substantially involved in myelopoiesis, but the role of miRNAs in the development of neutrophils remains elusive. In this study, we provided genetic evidence that miR-142-3p plays an essential role in the regulation of neutrophil homeostasis and maturation. Up to this point, the best-known miRNA that regulates neutrophil development is miR-223. A previous study in knockout mouse has revealed that miR-223 acts as a negative regulator of progenitor proliferation and granulocyte differentiation.7 As revealed by that study, miR-223-deficient neutrophils exhibit an unusual hypermature morphology that is characterized by nuclear hypersegmentation and blebbing, which is reminiscent of the granulocytes observed in human myelokathexis,44 and those abnormalities of neutrophils were also observed in our miR-142ab−/− knockout zebrafish. Moreover, a previous study showed that miR-142 is positively regulated by miR-223 in the myeloid cell line K562. Considering the ...
To determine if the SHIP phosphatase activity is sufficient to alter neutrophil motility, we ectopically expressed a membrane-bound form of the human SHIP1 phosphatase domain (aa364-826) in zebrafish neutrophils (Freeburn et al., 2002). Transient expression was achieved using the lyz promoter driving both the constitutively active SHIP1 phosphatase and EGFP expression with the viral 2A peptide system which allows multiple protein products to be expressed from a single transgene (Provost et al., 2007). Transient expression of this construct in Tg(mpx:mCherry) embryos allowed for mosaic expression of the phosphatase domain labeled with EGFP and mCherry to be compared to control neutrophils that expressed mCherry alone. Live imaging of neutrophil random motility in the head of 3 dpf embryos showed that ectopic expression of the SHIP1 phosphatase domain impaired neutrophil random motility as compared to control neutrophils (Fig. 4D-E; supplementary material Movie 7). By contrast, ectopic expression ...
Neutrophils (also called polymorphonuclear leukocytes, PMNs) are the most abundant white blood cells in humans and play a central role in innate host defense. Another distinguishing feature of PMNs is their short lifespan. Specifically, these cells survive for less than 24 hours in the bloodstream and are inherently pre-programed to die by constitutive apoptosis. Recent data indicate that this process is regulated by intracellular signaling and changes in gene expression that define an apoptosis differentiation program. Infection typically accelerates neutrophil turnover, and as such, phagocytosis-induced cell death (PICD) and subsequent clearance of the corpses by macrophages are essential for control of infection and resolution of the inflammatory response. Herein we reprise recent advances in our understanding of the molecular mechanisms of neutrophil apoptosis with a focus on regulatory factors and pathway intermediates that are specific to this cell type. In addition, we summarize mechanisms
Following inhibition of DPP1 in the rat, the NSP activity was determined by the amount of DPP1 inhibition and the turnover of neutrophils and is thus supportive of the role of neutrophil maturation in the activation of NSPs. Clinical trials to monitor the effect of a DPP1 inhibitor on NSPs should ta …
BioAssay record AID 101434 submitted by ChEMBL: Inhibition of leukotriene B4 (LTB4) binding to its receptor on intact human neutrophils.
Cystic fibrosis (CF) is an autosomal recessive disorder caused by mutations in the gene that codes for the CF trans-membrane conductance regulator. These mutations result in abnormal secretions viscous airways of the lungs, favoring pulmonary infection and inflammation in the middle of neutrophil recruitment. Recently it was described that neutrophils can contribute with disease pathology by extruding large amounts of nuclear material through a mechanism of cell death known as Neutrophil Extracellular Traps (NETs) into the airways of patients with CF. Additionally, NETs production can contribute to airway colonization with bacteria, since they are the microorganisms most frequently found in these patients. In this review, we will discuss the implication of individual or mixed bacterial infections that most often colonize the lung of patients with CF, and the NETs role on the disease.
TY - JOUR. T1 - Acute inflammatory reaction after myocardial ischemic injury and reperfusion. Development and use of a neutrophil-specific antibody. AU - Hawkins, Hal K.. AU - Entman, Mark L.. AU - Zhu, Jessica Y.. AU - Youker, Keith A.. AU - Berens, Kurt. AU - Doré, Monique. AU - Smith, C. Wayne. PY - 1996/6. Y1 - 1996/6. N2 - Reperfusion of the infarcted canine myocardium after 1 hour of ischemia is associated with an acute inflammatory infiltrate at the border of the infarct. In this paper, we demonstrate that early margination and emigration of neutrophils originate in thin-walled (∼5-μm) venous cisterns that average 200 μm in length and vary from 10 to 70 μm in width and show strong constitutive expression of both ICAM-1 and P-selectin; this class of vessels (venous cisterns) appears to be a unique feature in heart. A monoclonal antibody (SG8H6) with specificity for canine neutrophils was developed that allowed much more sensitive immunohistochemical detection of neutrophils in tissue ...
Neutrophil swarming is a specific type of neutrophil migration behaviour characterised by a high coordination between neutrophils, clustering of neutrophils to the inflammation site and signalling to other neutrophils further away. This specific type of migration rely on the production and secretion of LTB4 and on the use of integrins for neutrophil to stop at the cluster site. Tan, Sioh-Yang; Weninger, Wolfgang (February 2017). Neutrophil migration in inflammation: intercellular signal relay and crosstalk. Current Opinion in Immunology. 44: 34-42. doi:10.1016/j.coi.2016.11.002. L?mmermann, Tim; Afonso, Philippe V.; Angermann, Bastian R.; Wang, Ji Ming; Kastenm?ller, Wolfgang; Parent, Carole A.; Germain, Ronald N. (26 May 2013). Neutrophil swarms require LTB4 and integrins at sites of cell death in vivo. Nature. 498 (7454): 371-375. doi:10.1038/nature12175 ...
TY - JOUR. T1 - Endogenous nitric oxide inhibits neutrophil adherence to lung epithelial cells to modulate interleukin-8 release. AU - Lin, Horng Chyuan. AU - Wang, Chun Hua. AU - Yu, Chih Teng. AU - Hwang, Kuo Shiung. AU - Kuo, Han Pin. PY - 2001/8/3. Y1 - 2001/8/3. N2 - To investigate the effect of neutrophil adherence to epithelial cells on the release of interleukin 8 (IL-8), we measured neutrophil adherence in the presence or absence of IFN-γ+TNF-α+IL-1β (cytomix) stimulation on cultured A549 epithelial cells. The extent of neutrophil adherence to A549 epithelial cells was measured and the concomitant production of IL-8 and nitrite were assayed. The roles of adhesion molecules and nitrite in modulation of neutrophil adherence were examined by pretreatment with oversaturating ICAM-1 blocking antibody and L-NAME (1mM), respectively. There was a time-dependent spontaneous and cytomix-induced release of IL-8 from epithelial cells, as well as a time-dependent increase in the magnitude of ...
TY - CHAP. T1 - Neutrophil isolation from nonhuman species. AU - Siemsen, Daniel W.. AU - Malachowa, Natalia. AU - Schepetkin, Igor A.. AU - Whitney, Adeline R.. AU - Kirpotina, Liliya N.. AU - Lei, Benfang. AU - Deleo, Frank R.. AU - Quinn, Mark T.. PY - 2014. Y1 - 2014. N2 - The development of new advances in the understanding of neutrophil biochemistry requires effective procedures for isolating purified neutrophil populations. Although methods for human neutrophil isolation are now standard, similar procedures for isolating neutrophils from many of the nonhuman species used to model human diseases are not as well developed. Since neutrophils are reactive cells, the method of isolation is extremely important to avoid isolation technique-induced alterations in cell function. We present methods here for reproducibly isolating highly purified neutrophils from large animals (bovine, equine, ovine), small animals (murine and rabbit), and nonhuman primates (cynomolgus macaques), and describe ...
Neutrophil invasion of inflamed tissue is a complex process involving an initial mild adhesive interaction with the venular endothelium, termed rolling, which allows neutrophils to remain in close apposition to the endothelial cells and to sample the environment for local signals of an ongoing inflammatory process.1 2 3 If the appropriate signals (stimuli) are present, the neutrophils become activated, and a strong adhesive interaction takes place. This results in neutrophil arrest and eventual emigration toward the chemotactic stimulus in the interstitium. Although there is a general consensus on the mechanisms (adhesion molecule activation/expression) involved in neutrophil-endothelial cell adhesive interactions,1 2 3 the mechanisms by which neutrophils penetrate the endothelial cell lining to gain access to the interstitium remain controversial. The barriers to neutrophil movement to the site of chemotactic (or inflammatory) stimuli in the interstitium are (1) the endothelial cells lining the ...
Background: The inflamed bronchial mucosal surface is a profoundly hypoxic environment. Neutrophilic airway inflammation and neutrophil-derived proteases have been linked to disease progression in conditions such as COPD and cystic fibrosis, but the effects of hypoxia on potentially harmful neutrophil functional responses such as degranulation are unknown. Methods and results: Following exposure to hypoxia (0.8% oxygen, 3 kPa for 4 h), neutrophils stimulated with inflammatory agonists (granulocyte-macrophage colony stimulating factor or platelet-activating factor and formylated peptide) displayed a markedly augmented (twofold to sixfold) release of azurophilic (neutrophil elastase, myeloperoxidase), specific (lactoferrin) and gelatinase (matrix metalloproteinase-9) granule contents. Neutrophil supernatants derived under hypoxic but not normoxic conditions induced extensive airway epithelial cell detachment and death, which was prevented by coincubation with the antiprotease α-1 antitrypsin; ...
In contrast to other isolation techniques, neutrophils enriched by spontaneous sedimentation were found to be intact both in terms of their function and relative numbers within the
Although resistin was recently found to modulate insulin resistance in preclinical models of type II diabetes and obesity, recent studies also suggested that resistin has proinflammatory properties. We examined whether the human-specific variant of resistin affects neutrophil activation and the severity of LPS-induced acute lung injury. Because human and mouse resistin have distinct patterns of tissue distribution, experiments were performed using humanized resistin mice that exclusively express human resistin (hRTN +/-/-) but are deficient in mouse resistin. Enhanced production of TNF-α or MIP-2 was found in LPS-treated hRtn+/-/- neutrophils compared with control Rtn-/-/- neutrophils. Expression of human resistin inhibited the activation of AMPactivated protein kinase, a major sensor and regulator of cellular bioenergetics that also is implicated in inhibiting inflammatory activity of neutrophils and macrophages. In addition to the ability of resistin to sensitize neutrophils to LPS ...
Looking for online definition of neutrophil microbicidal assay in the Medical Dictionary? neutrophil microbicidal assay explanation free. What is neutrophil microbicidal assay? Meaning of neutrophil microbicidal assay medical term. What does neutrophil microbicidal assay mean?
Are neutrophil/lymphocyte ratio and platelet/lymphocyte ratio reliable parameters as prognostic indicators in malignant mesothelioma? Seda Tural Onur,1 Sinem Nedime Sokucu,1 Levent Dalar,2 Sinem Iliaz,1 Kaan Kara,1 Songül Buyukkale,3 Sedat Altin1 1Department of Chest Diseases, Yedikule Chest Diseases and Thoracic Surgery Training and Research Hospital, 2Department of Pulmonary Medicine, Faculty of Medicine, Istanbul Bilim University, 3Department of Thoracic Surgery, Yedikule Chest Diseases and Thoracic Surgery Training and Research Hospital, Istanbul, Turkey Background: Malignant mesothelioma (MM) is an aggressive asbestos-related pleural tumor. The incidence is increasing with intensive use of asbestos in developing countries. We need an easily accessible, inexpensive, and reliable method for determining the low survival time prognosis of this tumor. The aim of our study was to investigate the viability of neutrophil/lymphocyte ratio (NLR) and platelet/lymphocyte ratio (PLR) as prognostic
Results In vehicle treated neutrophils, there was increased viability and less apoptosis in bronchiectasis patients compared to healthy volunteers; Figure 1. There was a significant increase in CD11b upregulation; p = 0.01 and CD62L shedding; p = 0.01 in bronchiectasis patients compared to healthy volunteers. There was a significant increase in neutrophil degranulation with myeloperoxidase (MPO) release, in bronchiectasis patients; p = 0.04. There was an increase in neutrophil phagocytosis of GFP labelled Pseudomonas aeruginosa by neutrophils from bronchiectasis patients, p = 0.03, compared to healthy volunteers; Figure1.. In LXA4 treated neutrophils, there was no effect of LXA4 on spontaneous neutrophil apoptosis. There was a significant reduction in n-formyl-methyl-leucyl-phenylalanine (fMLF)-induced CD11b upregulation and CD62L shedding by LXA4 in a dose dependent manner in all three groups. There was a significant reduction in cytochalasin-B and fMLF-induced activation of neutrophils and ...
Serine proteinases of human polymorphonuclear neutrophils play an important role in neutrophil-mediated proteolytic events; however, the non-oxidative mechanisms by which the cells can degrade extracellular matrix in the presence of proteinase inhibitors have not been elucidated. Herein, we provide the first report that human neutrophils express persistently active cell surface-bound human leukocyte elastase and cathepsin G on their cell surface. Unstimulated neutrophils have minimal cell surface expression of these enzymes; however, phorbol ester induces a 30-fold increase. While exposure of neutrophils to chemoattractants (fMLP and C5a) stimulates modest (two- to threefold) increases in cell surface expression of serine proteinases, priming with concentrations of lipopolysaccharide as low as 100 fg/ml leads to striking (up to 10-fold) increase in chemoattractant-induced cell surface expression, even in the presence of serum proteins. LPS-primed and fMLP-stimulated neutrophils have ...
Helicobacter pylori (HP) can cause many diseases and malignant conditions. In the stomach, HP causes mucosal injury and inflammation. We determined the association of the platelet/lymphocyte ratio (PLR) and neutrophil/lymphocyte ratio (NLR) with HP-positive and HP-negative gastritis severity. We retrospectively reviewed 234 patients who had undergone upper gastrointestinal endoscopy for the investigation of dyspepsia and reflux symptoms. The patients were divided into three groups according to the results of the histopathologic evaluation: HP-negative gastritis group, HP-positive gastritis group and control group (neither HP positivity nor gastritis). We routinely collected laboratory data, including complete blood count, from all the patients. The mean neutrophil count was higher and the mean lymphocyte count was lower in the HP-positive gastritis group than in the other groups. The mean platelet count was increased in all groups, but the lowest increase was seen in the HP-positive gastritis ...
Neutrophils release neutrophil extracellular traps (NETs) which ensnare pathogens and have pathogenic functions in diverse diseases. We examined the NETosis pathways induced by five stimuli; PMA, the calcium ionophore A23187, nigericin, Candida albicans and Group B Streptococcus. We studied NET production in neutrophils from healthy donors with inhibitors of molecules crucial to PMA induced NETs including protein kinase C, calcium, reactive oxygen species, the enzymes myeloperoxidase (MPO) and neutrophil elastase. Additionally, neutrophils from chronic granulomatous disease patients, carrying mutations in the NADPH oxidase complex or a MPO-deficient patient were examined. We show that PMA, C. albicans and GBS use a related pathway for NET induction whereas ionophores require an alternative pathway but that NETs produced by all stimuli are proteolytically active, kill bacteria and composed mainly of chromosomal DNA. Thus, we demonstrate that NETosis occurs through several signalling mechanisms,
The Predictive Value of Total Neutrophil Count and Neutrophil/ Lymphocyte Ratio in Predicting In-hospital Mortality and Complications after STEMI ...
A wide variety of microbial and inflammatory factors induce DNA release from neutrophils as neutrophil extracellular traps (NETs). Consensus on the kinetics and mechanism of NET release has been hindered by the lack of distinctive methods to specifically quantify NET release in time. Here, we validate and refine a semi-automatic ... read more live imaging approach for quantification of NET release. Importantly, our approach is able to correct for neutrophil input and distinguishes NET release from neutrophil death by other means, aspects that are lacking in many NET quantification methods. Real time visualization shows that opsonized S. aureus rapidly induces cell death by toxins, while actual NET formation occurs after 90 minutes, similar to the kinetics of NET release by immune complexes and PMA. Inhibition of SYK, PI3K and mTORC2 attenuates NET release upon challenge with physiological stimuli but not with PMA. In contrast, neutrophils from chronic granulomatous disease patients show ...
Alpha-1 antitrypsin (AAT) deficiency (AATD) is characterised by excessive neutrophil degranulation and a protease: anti-protease imbalance leading to premature emphysema. Current specialised treatment for AATD consists of once weekly infusion of plasma purified AAT. Neutrophil degranulation is under the control of small GTP-binding proteins, including Ras-related C3 botulinum toxin substrate 2 (Rac2). The molecular basis for aberrant neutrophil degranulation in AATD has not been elucidated to date. The aim of this study was to fully characterise neutrophil degranulation in AATD and to determine the effects of AAT augmentation therapy on the AATD neutrophil. In this study, we examined degranulation by AATD neutrophils by Western blotting. This revealed a 3-fold increase in levels of myeloperoxidase (MPO), human cathelicidin antimicrobial protein (hCAP-18) and matrix metalloprotease-9 (MMP-9), markers of primary, secondary and tertiary granules, respectively (p=0.023, p=0.036 and p=0.042, respectively).
|jats:title|Abstract|/jats:title| |jats:sec| |jats:title|Background|/jats:title| |jats:p|Neutrophil activation results in Plasmodium parasite killing in vitro, but neutrophil products including neutrophil extracellular traps (NETs) mediate host organ damage and may contribute to severe malaria. The role of NETs in the pathogenesis of severe malaria has not been examined.|/jats:p| |/jats:sec| |jats:sec| |jats:title|Methods|/jats:title| |jats:p|In Papua, Indonesia, we enrolled adults with symptomatic Plasmodium falciparum (n = 47 uncomplicated, n = 8 severe), Plasmodium vivax (n = 37), or Plasmodium malariae (n = 14) malaria; asymptomatic P falciparum (n = 19) or P vivax (n = 21) parasitemia; and healthy adults (n = 23) without parasitemia. Neutrophil activation and NETs were quantified by immunoassays and microscopy and correlated with parasite biomass and disease severity.|/jats:p|
The production of reactive oxygen metabolites by neutrophils is thought to play a key role in host defense against invading microorganisms. In this study, the generation of oxygen metabolites induced by two uropathogenic Escherichia coli strains, ABU2 and PN7, and their subsequent killing in neutrophils were investigated. Both strains were grown to promote type 1 (mannose-sensitive) fimbria formation, but they differ with respect to other surface structures. When interacting with human neutrophils, the ABU2 bacteria adhered to and were phagocytized by the neutrophils, whereas PN7 bacteria adhered to the neutrophils but resisted phagocytosis. Both strains induced a pronounced neutrophil chemiluminescence response. However, when the intracellular and extracellular parts of the oxidative response were separated, we found that the predominant part of the response was of intracellular origin with the ABU2 bacteria as prey, whereas a large fraction of the response induced by the PN7 bacteria was ...
TY - JOUR. T1 - Source of iron in neutrophil-mediated killing of endothelial cells. AU - Gannon, D. E.. AU - Varani, J.. AU - Phan, S. H.. AU - Ward, J. H.. AU - Kaplan, J.. AU - Till, G. O.. AU - Simon, R. H.. AU - Ryan, U. S.. AU - Ward, P. A.. PY - 1987/9/10. Y1 - 1987/9/10. N2 - Recently we have shown that human neutrophils activated with phorbol ester are cytotoxic for cultured boving pulmonary artery endothelial cells in an iron-dependent manner. By using the ferric iron chelator deferoxamine mesylate, we have now investigated the source of the iron. Pretreatment of neutrophils with deferoxamine mesylate affected neither their production of O2- nor their cytotoxicity for endothelial cells after addition of phorbol ester. However, similar pretreatment of endothelial cells with deferoxamine mesylate, followed by washing of the cells, resulted in a persistent presence of chelator associated with the endothelial cells and high degrees of protection of endothelial cells from cytotoxicity. The ...
Both cis and trans unsaturated fatty acids and sodium dodecyl sulfate activated NADPH oxidase in plasma membranes of human neutrophils in the presence of neutrophil cytosol. In contrast, 5,8,11,14-icosatetraynoic acid, saturated fatty acids, esters, peroxides and 4 beta-phorbol 12-myristate 13-acetate, a potent activator of protein kinase C, were inactive. 5,8,11,14-icosatetraynoic acid inhibited superoxide formation elicited by fatty acids. Guanosine 5[gamma-thio]triphosphate (GTP[gamma S]), a potent activator of guanine-nucleotide-binding proteins (N-proteins) enhanced superoxide formation elicited by fatty acids up to fourfold, supporting our previous suggestion that NADPH oxidase is regulated by an N-protein [Seifert, R. et al. (1986) FEBS Lett. 205, 161-165]. Cytosols from various tissues, soybean lipoxygenase and protein kinase C, purified from chicken stomach, did not substitute neutrophil cytosol. The activity of neutrophil cytosol was destroyed by heating at 95 degrees C. Superoxide ...
Background: There is a direct relation between C-reactive protein and leukocyte count as indicators of inflammation. The neutrophil lymphocyte ratio (NLR) is the balance between both cells and is considered a marker of low-grade inflammation and an indicator of high risk of cardiovascular events. An elevated NLR is related with type 2 diabetes (T2D), however, even when in type 1 diabetes (T1D) there is an underlying inflammatory process, an elevation of circulating neutrophils isn t observed. NLR is associated with hyperglycemia in adult patients with long-duration T2D. However, reports in pediatric populations with recent-onset type 1 (T1D) and T2D are scarce.. Objective and hypotheses: To evaluate the association between NLR and the degree of glycemic control in pediatric patients with recent-onset T1D and T2D vs healthy controls.. Method: Design: Analytical cross-sectional. Subjects 8 16 years of age were included, with T1D or T2D with diagnosis ≤ 3 months, who, with their guardians, signed ...
Here we investigated microtubule dynamics and function during neutrophil migration in vivo. In accordance with reported in vitro findings, we found that microtubule disruption impairs neutrophil directed migration to wounds but induces cell motility and polarity in a PI(3)K-independent manner. We also found that Rho mediates nocodazole-induced neutrophil motility. These findings are consistent with previous findings in vitro, but further provide a physiological context for neutrophil migration. In addition, we elucidated two previously unidentified roles of microtubules during neutrophil motility in vivo. First, microtubule arrays nucleate in front of the nucleus and mainly radiate towards the uropod. Second, Rac is activated by microtubule depolymerization in primary human neutrophils and is necessary for nocodazole-induced neutrophil motility in vivo.. Leukocytes are often described as having the microtubule cytoskeleton and MTOC behind the nucleus at the uropod (Friedl and Weigelin, 2008; ...
We have previously shown that gadolinium oxide (Gd2O3) nanoparticles are promising candidates to be used as contrast agents in magnetic resonance (MR) imaging applications. In this study, these nanoparticles were investigated in a cellular system, as possible probes for visualization and targeting intended for bioimaging applications. We evaluated the impact of the presence of Gd2O3 nanoparticles on the production of reactive oxygen species (ROS) from human neutrophils, by means of luminol-dependent chemiluminescence. Three sets of Gd2O3 nanoparticles were studied, i.e. as synthesized, dialyzed and both PEG-functionalized and dialyzed Gd2O3 nanoparticles. In addition, neutrophil morphology was evaluated by fluorescent staining of the actin cytoskeleton and fluorescence microscopy. We show that surface modification of these nanoparticles with polyethylene glycol (PEG) is essential in order to increase their biocompatibility. We observed that the as synthesized nanoparticles markedly decreased the ...
Neutrophils play a critical role in host defense against invading pathogens. Chemotaxis, the directed migration of cells, allows neutrophil to seek out the sites of inflammation and infection. Neutrophil chemotaxis as well as other type of cell migration are considered as cycles composed of highly orchestrated steps. Recently the underlying signaling mechanisms of neutrophil chemotaxis are better understood with the studies in knockout mice and neutrophil-like cell lines: a number of signaling molecules in neutrophil chemotaxis have been identified, and a feedback loop-based model of frontness and backness pathways has been proposed to explain the establishment of neutrophil polarity and chemotaxis. However, the signaling mechanisms that control actin cytoskeleton reorganization and interaction between the cells and the substratum on which cells migrate are still not fully understood. In my first research project, we have identified a signaling pathway, mediated by non-receptor tyrosine ...
TY - JOUR. T1 - Neutrophil Extracellular Traps Enhance Staphylococcus Aureus Vegetation Formation through Interaction with Platelets in Infective Endocarditis. AU - Hsu, Chih-Chieh. AU - Hsu, Ron-Bin. AU - Ohniwa, Ryosuke L. AU - Chen, Jeng-Wei. AU - Yuan, Chang-Tsu. AU - Chia, Jean-San. AU - Jung, Chiau-Jing. N1 - Georg Thieme Verlag KG Stuttgart · New York.. PY - 2019/5. Y1 - 2019/5. N2 - The mechanisms or host factors involved in septic thrombus or vegetation formation in Staphylococcus aureus-induced infective endocarditis (IE) are unclear. Using an experimental endocarditis rat model, here we demonstrated that S. aureus HG001-induced vegetation was composed of bacterial floes encased in aggregated platelets and surrounded by neutrophil extracellular traps (NETs). In vitro data demonstrated that platelets contribute to both biofilm and NET formation. Prophylactic administration of DNase I significantly reduced the size of vegetation induced by methicillin-resistant S. aureus (MRSA) and ...
Introduction Neutrophils accumulate in the lungs of patients with bronchiectasis and cystic fibrosis, and the resulting inflammation causes tissue hypoxia. Neutrophils have a unique ability to survive and function in such hypoxic environments, a response regulated by the hypoxia-inducible transcription factor (HIF)/hydroxylase oxygen sensing pathway.. Pseudomonas aeruginosa is an opportunistic pathogen which colonises patients with chronic lung disease, including cystic fibrosis. It secretes the toxin pyocyanin, which induces neutrophil apoptosis in an oxygen-dependent manner, as a means of immune-evasion. P. aeruginosa has recently been shown to possess hydroxylase-homologs, suggesting that prokaryotes may also have oxygen-sensing capabilities. A prolyl-hydroxylase (PHD)-deficient strain secretes higher levels of pyocyanin compared with wild-types.. We hypothesised that PHD-deficient P. aeruginosa induces a higher degree of neutrophil death compared with an otherwise genetically identical ...
Synergistic regulation of endogenous TRPM2 channels by adenine dinucleotides in primary human neutrophils. Cell Calcium.2008 Dec;44(6):604-15; Epub 2008 Jun 24; PubMed Central PMCID: PMC2597220.PMED ID: 18572241. ...
article{f7336ebb-e740-4acd-bf1a-ccf3f3a2c8e1, author = {Weineisen, Maria and Sjöbring, Ulf and Fällman, Maria and Andersson, Tommy}, issn = {1550-6606}, language = {eng}, number = {6}, pages = {3798--3807}, publisher = {American Association of Immunologists}, series = {Journal of Immunology}, title = {Streptococcal M5 protein prevents neutrophil phagocytosis by interfering with CD11b/CD18 receptor-mediated association and signaling.}, volume = {172}, year = {2004 ...
COVID-19 affects millions of patients worldwide with clinical presentation ranging from isolated thrombosis to acute respiratory distress syndrome (ARDS) requiring ventilator support. Neutrophil extracellular traps (NETs) originate from decondensed chromatin released to immobilize pathogens and can trigger immunothrombosis. We studied the connection between NETs and COVID-19 severity and progression. We conducted a prospective cohort study of COVID-19 patients (n=33) with age- and sex-matched controls (n=17). We measured plasma myeloperoxidase (MPO)-DNA complexes (NETs), Platelet Factor 4, RANTES, and selected cytokines. Three COVID-19 lung autopsies were examined for NETs and platelet involvement. We assessed NET formation ex vivo in COVID-19 neutrophils and in healthy neutrophils incubated with COVID-19 plasma. We also tested the ability of neonatal NET-Inhibitory Factor (nNIF) to block NET formation induced by COVID-19 plasma. Plasma MPO-DNA complexes increased in COVID-19 with intubation ...
Neutrophil granulocytes constitute the front line of defense in the innate immune response to invading microorganisms, but can also contribute to development of inflammatory disease and tissue destruction following e.g. myocardial infarction or stroke. During inflammatory activation, neutrophils leave the blood, interact with extracellular matrix proteins, and migrate into tissues in response to chemotactic factors to phagocytose and kill infectious agents by using toxic granule contents and reactive oxygen metabolites. The functional neutrophil response relies on exocytosis of cytoplasmic granules, each containing membrane proteins, which are thereby mobilized to the plasma membrane. Specific programmed cell death (apoptotic) pathways regulate neutrophil homeostasis, where an inflammatory milieu can prolong the life span of neutrophils to several days, whereas non-activated neutrophils are committed to constitutive/spontaneous apoptosis within hours.. Signal regulatory protein alpha (SIRPα) is ...
Activated neutrophils release proteases that function in neutrophil extracellular traps to mediate bacterial killing and that also function as autocrine regulators of neutrophil function. Previous work had shown that neutrophils deficient in two proteases, cathepsin G and elastase (CG/NE), did not respond to activation by immune complexes in vitro and that the response was restored by exogenous addition of cathepsin G. Woloszynek et al. performed a proteomic proteolysis screen of CG/NE-deficient neutrophils stimulated with immune complexes and then treated with cathepsin G and identified four candidate targets of cathepsin G. Of these, Annexin A1 (AnxA1) and CRAMP (the mouse ortholog of human cathelicidin) had been previously reported as substrates of serine proteases that modulate neutrophil function, and those were selected for further evaluation. Both AnxA1 and CRAMP were substrates of cathepsin G in vitro, with AnxA1 cleaved to the active product and CRAMP only partially cleaved. Comparison ...
Neutrophil extracellular traps (NETs) have been implicated in the pathogenesis of systemic Lupus erythematosus (SLE), since netting neutrophils release potentially immunogenic autoantigens including histones, LL37, human neutrophil peptide (HNP), and self-DNA. In turn, these NETs activate plasmacytoid dendritic cells resulting in aggravation of inflammation and disease. How suppression of NET formation can be targeted for treatment has not been reported yet. Signal Inhibitory Receptor on Leukocytes-1 (SIRL-1) is a surface molecule exclusively expressed on phagocytes. We recently identified SIRL-1 as a negative regulator of human neutrophil function. Here, we determine whether ligation of SIRL-1 prevents the pathogenic release of NETs in SLE. Peripheral blood neutrophils from SLE patients with mild to moderate disease activity and healthy donors were freshly isolated. NET release was assessed spontaneously or after exposure to anti-neutrophil antibodies or plasma obtained from SLE patients. The ...
TY - JOUR. T1 - Conditioned medium from stimulated mononuclear leucocytes potentiates the ability of human neutrophils do damage human articular cartilage. AU - Bates, E. J.. AU - Kowanko, I. C.. AU - Ferrante, A.. N1 - Copyright: Copyright 2017 Elsevier B.V., All rights reserved.. PY - 1988. Y1 - 1988. N2 - Human neutrophils were able to degrade proteoglycan and inhibit its synthesis when incubated with human articular cartilage coated with heat aggregated immunoglobulin G. These effects were potentiated when culture medium conditioned by mononuclear leucocytes stimulated with killed Staphylococcus aureus was also present during the incubations. Neutrophils preincubated with this conditioned medium and washed before incubation with cartilage also showed an increased ability to degrade proteoglycan and inhibit its synthesis. The percentage of neutrophils binding to cartilage was significantly increased in the presence of this conditioned medium.. AB - Human neutrophils were able to degrade ...
The coronavirus disease 2019 (COVID-19) has become a pandemic. Rapidly distinguishing COVID-19 from other respiratory infections is a challenge for first-line health care providers. This retrospective study was conducted at the Taipei Medical University Hospital, Taiwan. Patients who visited the outdoor epidemic prevention screening station for respiratory infection from February 19 to April 30, 2020, were evaluated for blood biomarkers to distinguish COVID-19 from other respiratory infections. Monocyte distribution width (MDW) ≥ 20 (odds ratio [OR]: 8.39, p = 0.0110, area under curve [AUC]: 0.703) and neutrophil-to-lymphocyte ratio (NLR) | 3.2 (OR: 4.23, p = 0.0494, AUC: 0.673) could independently distinguish COVID-19 from common upper respiratory tract infections (URIs). Combining MDW ≥ 20 and NLR | 3.2 was more efficient in identifying COVID-19 (AUC: 0.840). Moreover, MDW ≥ 20 and NLR | 5 effectively identified influenza infection (AUC: 0.7055). Thus, MDW and NLR can distinguish COVID-19 from
We have developed induced pluripotent stem cells (iPSCs) from a patient with X-linked chronic granulomatous disease (X-CGD), a defect of neutrophil microbicidal reactive oxygen species (ROS) generation resulting from gp91phox deficiency. We demonstrated that mature neutrophils differentiated from X-CGD iPSCs lack ROS production, reproducing the pathognomonic CGD cellular phenotype. Targeted gene transfer into iPSCs, with subsequent selection and full characterization to assure no off-target changes, holds promise for correction of monogenic diseases without the insertional mutagenesis caused by multisite integration of viral or plasmid vectors. Zinc finger nuclease mediated gene targeting of a single copy gp91phox therapeutic minigene into one allele of the safe harbor AAVS1 locus in X-CGD iPSCs without off-target inserts resulted in sustained expression of gp91phox and substantially restored neutrophil ROS production. Our findings demonstrate how precise gene targeting may be applied to ...
Neutrophil-To-Lymphocyte Ratio (NLR) Platelet-To-Lymphocyte Ratio (PLR), and Outcomes With Nivolumab in Pretreated Non-Small Cell Lung Cancer (NSCLC): A Large Retrospective Multicenter Study
Background: In this study, we explored the relationship between                  neutrophil-to-lymphocyte ratio (NLR) and grade 3 or higher treatment related small bowel toxicity and treatment outcome of patients with rectal cancer undergoing capecitabine and concurrent intensity modulated radiotherapy (IMRT). Materials and Methods: From the year of 2012 to 2013, 117 rectal cancer ...
BACKGROUND: The preoperative neutrophil-to-lymphocyte ratio (NLR) and the platelet-to-lymphocyte ratio (PLR) are associated with poor prognosis of gastric cancer. We aimed to determine whether the combination of NLR and PLR (NLR-PLR) could better predict survival of patients after curative resection for stage I-II gastric cancer.. METHODS: We collected data from the medical records of patients with stage I-II gastric cancer undergoing curative resection between December 2000 and November 2012 at the Sun Yat-sen Cancer Center. The preoperative NLR-PLR was calculated as follows: patients with both elevated NLR (≥2.1) and PLR (≥120) were given a score of 2, and patients with only one or neither were given a score of 1 or 0, respectively.. RESULTS: Kaplan-Meier analysis and log-rank tests revealed significant differences in overall survival (OS) among patients with NLR-PLR scores of 0, 1 and 2 (P , 0.001). Multivariate analysis showed that OS was independently associated with the NLR-PLR score ...
The prognostic significance of neutrophil-to-lymphocyte ratio at different time points in patients with hepatocellular carcinoma receiving liver resection
Postoperative neutrophil-to-lymphocyte ratio change is a potential marker for the early detection of recurrence in urothelial carcinoma
The application of fluid shear stress on leukocytes is critical for physiological functions including initial adhesion to the endothelium, the formation of pseudopods, and migration into tissues. The formyl peptide receptor (FPR) on neutrophils, which binds to formyl-methionyl-leucyl-phenylalanine (fMLP) and plays a role in neutrophil chemotaxis, has been implicated as a fluid shear stress sensor that controls pseudopod formation. The role of shear forces on earlier indicators of neutrophil activation, such as L-selectin shedding and α(M)β(2) integrin activation, remains unclear. Here, human neutrophils exposed to uniform shear stress (0.1-4.0 dyn/cm(2)) in a cone-and-plate viscometer for 1-120 min showed a significant reduction in both α(M)β(2) integrin activation and L-selectin shedding after stimulation with 0.5 nM of fMLP. Neutrophil resistance to activation was directly linked to fluid shear stress, as the response increased in a shear stress force- and time-dependent manner. Significant shear
TY - JOUR. T1 - Inhibition of CD18-dependent neutrophil adherence reduces organ injury after hemorrhagic shock in primates. AU - Mileski, W. J.. AU - Winn, R. K.. AU - Vedder, N. B.. AU - Pohlman, T. H.. AU - Harlan, J. M.. AU - Rice, C. L.. PY - 1990. Y1 - 1990. N2 - Neutrophil adherence or aggregation may be important in the development of organ injury after hemorrhagic shock. Monoclonal antibody (MAb) 60.3 prevents both adherence and aggregation. Therefore we investigated MAb 60.3 treatment in prevention of organ injury after hemorrhagic shock in rhesus monkeys (Macaca mulatta). We performed esophagogastroscopy and placed catheters to measure cardiac output, mean arterial pressure, arterial blood gases, and urine output. Blood was removed to decrease CO to 30% of baseline for 90 minutes. Just before resuscitation, MAb 60.3 (2 mg/kg) or saline solution (control) was administered intravenously. Monitoring and fluid resuscitation continued for 24 hours, with lactated Ringers solution given as a ...
TY - JOUR. T1 - Adherent neutrophils activate endothelial myosin light chain kinase. T2 - Role in transendothelial migration. AU - Garcia, Joe G.N.. AU - Verin, Alexander D.. AU - Herenyiova, Maria. AU - English, Denis. PY - 1998/5/1. Y1 - 1998/5/1. N2 - Increased vascular endothelial cell (EC) permeability and neutrophilic leukocyte (PMN) diapedesis through paracellular gaps are cardinal features of acute inflammation. Activation of the EC contractile apparatus is necessary and sufficient to increase vascular permeability in specific models of EC barrier dysfunction. However, it is unknown whether EC contraction with subsequent paracellular gap formation is required for PMN transendothelial migration in response to chemotactic factors. To test this possibility, we assessed migration of human PMNs across confluent bovine pulmonary arterial EC monolayers. Transendothelial PMN migration in the absence of a chemotactic gradient was minimal, whereas abluminal addition of leukotriene B4 (LTB4; 5 μM) ...
Role of Neutrophils in Fibrin Structure and Function: How do Cells, Fibrin and Neutrophil Extracellular Traps (NETs) Integrate in Thrombi and Blood Cl, School of Medicine, University of Leeds
Immunoglobulin intravenous (IVIG) is widely used in mucocutaneous lymph node syndrome, known as Kawasaki disease (KD). However, the patients inflammatory response during usage remains unclear. In the present study, the association between inflammatory response and lymphocyte count in children with KD from different ages was evaluated before and after IVIG. The medical records of 50 children with KD were retrospectively reviewed and divided into five groups according to age. As compared with the data from healthy children, the relative neutrophil count of all children with KD was increased, and that of lymphocytes was decreased. The neutrophil/lymphocyte ratio (NLR) was different among all groups and was higher in children aged ≥4 years, as compared with other groups. Following IVIG, the relative neutrophil and lymphocyte counts of all children with KD returned to normal levels. The altered levels of neutrophils and lymphocytes were found to be linearly correlated. The correlation coefficient in the
The presence of anti-neutrophil cytoplasmic antibodies (ANCA) in Wegeners granulomatosis (WG), implicate the neutrophil as a key effector cell. Previous studies have reported elevated neutrophil counts in the lung although the determinants of neutrophil chemotaxis in the WG lung are unknown.. BALF cell counts, myeloperoxidase (MPO) and chemokines were measured in 27 patients with WG, 20 disease controls with idiopathic pulmonary fibrosis (IPF) and 6 healthy controls. CXCL-8, IL-1β, ENA-78, G-CSF and GM-CSF were measured by ELISA. The neutrophil chemotactic potential of BALF was investigated using the under agarose method and specific antibodies examined the role of CXCL-8 and IL-1β.. WG BALF had an increased neutrophil percentage and elevated MPO, CXCL-8 and G-CSF concentrations compared with healthy controls. Chemotaxis of control neutrophils towards BALF from patients with active (p=0.006) and remission WG (p=0.077) and IPF patients (p=0.001) was increased compared with normal controls. ...
Background: Clinical and experimental studies showing lung damage associated with biologically active neutrophil derivatives suggests the possibility that intrauterine neutrophil activation may predispose to the development of pulmonary haemorrhage in extremely low birthweight infants early after birth.. Objectives: To assess neutrophil functional activity in cord blood from extremely low birthweight infants who subsequently developed severe pulmonary haemorrhage.. Methods: Neutrophil functional activity was evaluated in the cord blood of preterm neonates (gestational age ,28 weeks and weight ,800 g) who developed pulmonary haemorrhage (n = 6) and in controls who did not (n = 6). Infants with congenital abnormalities and noteworthy maternal complications such as diabetes, pre-eclampsia, haemorrhagic disorders, and connective tissue disease were excluded. Neutrophils isolated from cord blood immediately after delivery were tested to evaluate neutrophil chemotaxis, random motility, and ...
alpha-Tocopherol augmentation in human neutrophils was investigated for effects on neutrophil activation and tyrosine phosphorylation of proteins, through its modulation of protein kinase C (PKC) and tyrosine phosphatase activities. Incubation of neutrophils with alpha-tocopherol succinate (TS) resulted in a dose-dependent incorporation into cell membranes, up to 2.5 nmol/2 X 10(6) cells. A saturating dose of TS (40 mumol/l) inhibited oxidant production by neutrophils stimulated with phorbol myristate acetate (PMA) or opsonized zymosan (OZ) by 86 and 57%, as measured by luminol-amplified chemiluminescence (CL). With PMA, TS inhibited CL generation to a similar extent to staurosporine (10 nmol/l) or genistein (100 mumol/l), and much more than Trolox (40 mumol/l). With OZ, TS inhibited CL to a similar extent to Trolox. Neutrophil PKC activity was inhibited 50% or more by TS or staurosporine. the enzyme activity was unaffected by genistein or Trolox, indicating a specific interaction of ...
Neutrophil to lymphocyte ratio see Neutrophil to lymphocyte ratio for subarachnoid hemorrhage. see Neutrophil to lymphocyte ratio for glioma. see Neutrophil to lymphocyte ratio for intracerebral hemorrhage. Normal Neutrophil to lymphocyte ratio values in an adult, non-geriatric, population in good health are between 0.78 and 3.53. These data may help the researcher as the clinician searching for a cut-off for the NLR, until now lacking
Neither dead cell debris nor attacking microorganisms can be dealt with effectively by the neutrophils. Unlike neutrophils, ... neutrophil-killers and neutrophil-cagers. They defend against bacterial or fungal infection. They are usually first responders ... A decrease in levels of neutrophils on lab tests is due to either decreased production of neutrophils or increased removal from ... Neutrophils are active in phagocytosing bacteria and are present in large amount in the pus of wounds. These cells are not able ...
Neutrophils do not normally exit the bone marrow until maturity, but during an infection neutrophil precursors called ... Neutrophils do not return to the blood; they turn into pus cells and die.[7] Mature neutrophils are smaller than monocytes, and ... neutrophils,[5] which are about 12-15 micrometers in diameter.[6] Once neutrophils have received the appropriate signals, it ... and generation of neutrophil extracellular traps (NETs).[9] Neutrophils are professional phagocytes:[10] they are ferocious ...
Neutrophil dysfunction[edit]. In widespread diseases such as sepsis, leukocyte extravasation enters an uncontrolled stage, ... Neutrophils extravasate from blood vessels to the site of tissue injury or infection during the innate immune response. ... Neutrophil dysfunction is usually preceded by an infection of some sort, which triggers pathogen-associated molecular patterns ... In other words, adhesion of neutrophils is heavily impacted by shear forces as well as molecular interactions. Moreover, as ...
This process characterizes neutrophils as a type of phagocyte. Neutrophils contain neutrophil extracellular traps (NETs), ... Neutrophils are a type of phagocyte, abundant in blood, that phagocytize pathogens in acute inflammation. Neutrophils, along ... After stimulation of the neutrophil response, neutrophils lose their shape, allowing euchromatin and heterochromatin to ... Neutrophils are some of the first immune cells to travel to sites of infection that aid in fighting infection by ingesting ...
Chemical factors produced during inflammation attract phagocytes, especially neutrophils.[5] Neutrophils then trigger other ... Neutrophil granules contain a variety of toxic substances that kill or inhibit growth of bacteria and fungi. The main products ... Neutrophils are the most abundant type of phagocyte, with 50 to 60% of the total circulating leukocytes. They are usually the ... Neutrophils and two other cell types (eosinophils and basophils), are known as granulocytes (because they have granules in ...
Neutrophils[change , change source]. Neutrophils are the most abundant type of white blood cells in mammals, 70% of leukocytes ...
... neutrophils, dendritic cells, mast cells, eosinophils, basophils, etc.) in variable proportions. Their abundance varies with ... "high neutrophils". Science. 358 (6367): eaal5081. doi:10.1126/science.aal5081. PMC 6343476. PMID 29191879. Gentles AJ, Newman ...
van Rees DJ, Szilagyi K, Kuijpers TW, Matlung HL, van den Berg TK (April 2016). "Immunoreceptors on neutrophils". Seminars in ... self-antigens or self-structures that play major role in inhibiting harmful immune system activity by regulating neutrophils ...
Also present are neutrophils and red blood cells in large numbers. The red blood cells are due to the proliferation of vaginal ... Neutrophils are increased. Red blood cells may be absent or present. Bacteria is commonly observed. A smear made during late ... No neutrophils are seen unless there is inflammation. There is usually no mucous in the background. In diestrus, superficial ... Late-proestrus - there is a decrease in neutrophils because they are unable to cross the thickening vaginal wall. Cytology ...
Segal AW (2005). "How neutrophils kill microbes". Annu. Rev. Immunol. 23: 197-223. doi:10.1146/annurev.immunol.23.021704.115653 ... platelets and polymorphonuclear neutrophils of patients with sickle cell disease exhibit oxidative stress that can be ...
Sengeløv H (1996). "Complement receptors in neutrophils". Critical Reviews in Immunology. 15 (2): 107-31. doi:10.1615/ ...
Neutrophils carry MMP-9., which has also been shown to degrade occludin. This leads to further disruption of the BBB and BSCB ... The increase in blood-brain barrier and blood-spinal cord barrier permeability allows for more neutrophils to infiltrate the ... Gurney KJ, Estrada EY, Rosenberg GA (Jul 2006). "Blood-brain barrier disruption by stromelysin-1 facilitates neutrophil ... "Neutrophils mediate blood-spinal cord barrier disruption in demyelinating neuroinflammatory diseases". Journal of Immunology. ...
Polymorphonuclear neutrophilsEdit. Within an hour of wounding, polymorphonuclear neutrophils (PMNs) arrive at the wound site ... Neutrophils phagocytise debris and kill bacteria by releasing free radicals in what is called a 'respiratory burst.[20][21] ... Functional neutrophils at the wound site only have life-spans of around 2 days, so they usually undergo apoptosis once they ... As inflammation dies down, fewer inflammatory factors are secreted, existing ones are broken down, and numbers of neutrophils ...
A naive (or inexperienced) B cell is one which belongs to a clone which has never encountered the epitope to which it is specific. In contrast, a memory B cell is one which derives from an activated naive or memory B cell. The activation of a naive or a memory B cell is followed by a manifold proliferation of that particular B cell, most of the progeny of which terminally differentiate into plasma B cells;[note 8] the rest survive as memory B cells. So, when the naive cells belonging to a particular clone encounter their specific antigen to give rise to the plasma cells, and also leave a few memory cells, this is known as the primary immune response. In the course of proliferation of this clone, the B cell receptor genes can undergo frequent (one in every two cell divisions)[8] mutations in the genes coding for paratopes of antibodies. These frequent mutations are termed somatic hypermutation. Each such mutation alters the epitope-binding ability of the paratope slightly, creating new clones of ...
... is leukocytosis of neutrophils, that is, a high number of neutrophils in the blood. Because neutrophils are the main type of ... A "left shift" refers to the presence of increased proportions of younger, less well differentiated neutrophils and neutrophil- ... Neutrophils are also increased in any acute inflammation, so will be raised after a heart attack, other infarct or burns. Some ... Neutrophils are the primary white blood cells that respond to a bacterial infection, so the most common cause of neutrophilia ...
Attracts macrophages, monocytes and neutrophils. Macrophage inflammatory proteins ENSG00000277632, ENSG00000274221 GRCh38: ... "Macrophages secrete a novel heparin-binding protein with inflammatory and neutrophil chemokinetic properties". The Journal of ...
PRTN3 is a serine protease enzyme expressed mainly in neutrophil granulocytes. Its exact role in the function of the neutrophil ... It is also the target of anti-neutrophil cytoplasmic antibodies (ANCAs) of the c-ANCA (cytoplasmic subtype) class, a type of ... Ohlsson K, Linder C, Rosengren M (July 1990). "Monoclonal antibodies specific for neutrophil proteinase 4. Production and use ... Kettritz R (September 2016). "Neutral serine proteases of neutrophils". Immunological Reviews. 273 (1): 232-48. doi:10.1111/imr ...
Neutrophils may fill some ducts. It is characterized as a "fissured" or "dried mud" appearance from excess keratin production ...
There is an accumulation of mononuclear cells and neutrophils around the blood vessels (perivascular) of the CNS. Meningitis is ... Typically small mature lymphocytes are the majority of cells seen, with monocytes and neutrophils making up the rest. ... CSF analysis shows predominantly neutrophils. In Beagles this condition is also known as Beagle pain syndrome. Eosinophilic ...
... neutrophils, basophils, monocytes, and eosinophils; or 2) lymphoid precursor cells which differentiate into T lymphocytes, B ...
Neutrophils and other phagocytes use peroxide to kill bacteria. The enzyme NADPH oxidase generates superoxide within the ... Winterbourn, Christine C.; Kettle, Anthony J.; Hampton, Mark B. (2016-06-02). "Reactive Oxygen Species and Neutrophil Function ... Murphy, Patrick (2012-12-06). The Neutrophil. Springer Science & Business Media. ISBN 9781468474183. Le, Tao; Bhushan, Vikas ( ...
Dockrell, David H.; McGrath, Emmet E.; Whyte, Moria K.B.; Sabroe, Ian (2007). "The Neutrophil". Immunology of Fungal Infections ... In healthy people, innate and adaptive immune responses are triggered by various immune cells (notably neutrophils, resident ... Proteases released by both the fungus and neutrophils induce further injury to the respiratory epithelium, leading to ...
Neutrophil actin dysfunction and abnormal neutrophil behavior. New Engl J Med. 1974; 291:1093-1099. 26. Smith AL, Rosenberg I, ... Neutrophil actin dysfunction is a genetic disorder associated with partial impairment of neutrophil actin assembly in three ... Neutrophil function tests and neutrophil transfusion. Exp Hemat. 1977; 5:9-14. 22. Stossel TP. Phagocytosis: clinical disorders ... Neutrophil function: normal and abnormal. In: Gordon AS, Silber R, LoBue J, eds. The Year in Hematology. New York: Plenum ...
Neutrophil collagenase. CLG1, HNC, MMP-8, PMNL-CL. secreted. Substrates include Col I, II, III, VII, VIII, X, aggrecan, gelatin ...
Defensin, alpha 4 (DEFA4), also known as neutrophil defensin 4 or HNP4, is a human defensin peptide that is encoded by the ... HNP4 is expressed in the granules of the neutrophil where it defends the host against bacteria and viruses. Defensins are a ... 3 January 2005). "Human neutrophil alpha-defensin 4 inhibits HIV-1 infection in vitro". FEBS Lett. 579 (1): 162-6. doi:10.1016/ ... 1989). "Purification and characterization of human neutrophil peptide 4, a novel member of the defensin family". J. Biol. Chem ...
... neutrophil-killers and neutrophil-cagers. One litre of human blood contains about five billion (5x109) neutrophils, which are ... Neutrophils do not return to the blood; they turn into pus cells and die. Mature neutrophils are smaller than monocytes, and ... Neutrophils do not normally exit the bone marrow until maturity, but during an infection neutrophil precursors called ... and generation of neutrophil extracellular traps (NETs). Neutrophils are professional phagocytes: they are ferocious eaters and ...
Neutrophils begin to fill the pustule. Toxins are produced by S. aureus and target desmoglein, which is a desmosomal cell-cell ...
Neutrophils are numerous in pleural empyema. If lymphocytes predominate and mesothelial cells are rare, this is suggestive of ...
It leads to the production of three types of mature granulocytes: neutrophils (most abundant, making up to 60% of all white ... Summers C, Rankin SM, Condliffe AM, Singh N, Peters AM, Chilvers ER (August 2010). "Neutrophil kinetics in health and disease ... Lawrence SM, Corriden R, Nizet V (June 2018). "The Ontogeny of a Neutrophil: Mechanisms of Granulopoiesis and Homeostasis". ... Cowland JB, Borregaard N (September 2016). "Granulopoiesis and granules of human neutrophils". Immunological Reviews. 273 (1): ...
Neutrophils phagocytose mainly via the Fcγ receptors and complement receptors 1 and 3. The microbicidal effect of neutrophils ... The role of neutrophils is patrolling the bloodstream and rapid migration to the tissues in large numbers only in case of ... Play media Neutrophils, macrophages, monocytes, dendritic cells, osteoclasts and eosinophils can be classified as professional ... After ingestion, neutrophils are efficient in intracellular killing of pathogens. ...
Inhibition of leukotriene B4 formation in rat peritoneal neutrophils by an ethanolic extract of the gum resin exudate of ...
Neutrophils may be subdivided into segmented neutrophils and banded neutrophils (or bands). They form part of the ... Neutrophil antigens[edit]. There are five (HNA 1-5) sets of neutrophil antigens recognized.[49] The three HNA-1 antigens (a-c) ... Normally, neutrophils contain a nucleus divided into 2-5 lobes. Neutrophils are a type of phagocyte and are normally found in ... Neutrophils will show increasing segmentation (many segments of the nucleus) as they mature. A normal neutrophil should have 3- ...
Neutrophils are produced in the bone marrow and released into the bloodstream to travel ... Neutrophils are a type of white blood cell that is responsible for much of the bodys protection against infection. ... Neutrophils are a type of white blood cell that is responsible for much of the bodys protection against infection. Neutrophils ... Large numbers of immature forms of neutrophils, called neutrophilic band cells, are produced by the bone marrow when the demand ...
Absence of Neutrophils Br Med J 1964; 2 :892 doi:10.1136/bmj.2.5414.892 ... Absence of Neutrophils. Br Med J 1964; 2 doi: (Published 10 October 1964) Cite this as: ...
Phagocytosis is central to the microbicidal function of neutrophils. Pathogens are initially engulfed into a plasma membrane- ... Phagocytosis by neutrophils Microbes Infect. 2003 Nov;5(14):1299-306. doi: 10.1016/j.micinf.2003.09.014. ... Phagocytosis is central to the microbicidal function of neutrophils. Pathogens are initially engulfed into a plasma membrane- ... we discuss the current knowledge of the molecular mechanisms underlying phagosome formation and maturation in neutrophils. ...
Neutrophils are a type of white blood cell that helps your body fight infection. You may develop low levels of neutrophils, ... Staying Healthy with Low Neutrophils * {"smallUrl":"https:\/\/\/images\/thumb\/5\/5b\/Raise-Neutrophils-Step-11. ... Neutrophils are a type of white blood cell that helps your body fight infection. You may develop low levels of neutrophils, ... If your neutrophils are low because of cancer treatment, talk to your doctor about getting a prescription for neutrophil- ...
Source for information on neutrophil: A Dictionary of Biology dictionary. ... neutrophil A type of white blood cell (leucocyte) that has a lobed nucleus and granular cytoplasm (see granulocyte). ... neutrophil A type of white blood cell (leucocyte) that has a lobed nucleus and granular cytoplasm (see granulocyte). ... neutrophil A Dictionary of Biology © A Dictionary of Biology 2004, originally published by Oxford University Press 2004. ...
Isolation of murine neutrophils from several anatomical compartments allows for functional characterization and analysis of ... Ubags N.D.J., Suratt B.T. (2018) Isolation and Characterization of Mouse Neutrophils. In: Alper S., Janssen W. (eds) Lung ... Isolation of murine neutrophils from several anatomical compartments allows for functional characterization and analysis of ... Summers C, Rankin SM, Condliffe AM, Singh N, Peters AM, Chilvers ER (2010) Neutrophil kinetics in health and disease. Trends ...
"The impact of cationic solid lipid nanoparticles on human neutrophil activation and formation of neutrophil extracellular traps ... "Cationic liposomes evoke proinflammatory mediator release and neutrophil extracellular traps (NETs) toward human neutrophils," ... Activation of Neutrophils by Nanoparticles. David M. Goncalves, Rafael de Liz, and Denis Girard ... K. Babin, D.M. Goncalves, and D. Girard, "Nanoparticles enhance the ability of human neutrophils to exert phagocytosis by a Syk ...
Dental plaque increases neutrophil activity in black males Will neglecting to brush your teeth damage more than just your smile ...
Your doctor may request an absolute neutrophils count (ANC) to help diagnose various medical conditions. ... Neutrophils are a type of white blood cell. ... Absolute neutrophil count (ANC). An absolute neutrophil count ( ... neutrophils (ANC). 1,500-8,000 (1.5-8.0) neutrophils/mcL. 45-75% of total white blood cells. mild: 1,000-1,500 neutrophils/mcL ... What causes low neutrophil levels?. Neutropenia is the term for low neutrophil levels. Low neutrophil counts are most often ...
Excessive leukocyte activation (including neutrophils and monocyte-macrophage lineage) with cytokinemia play a critical role in ...
Neutrophils, along with eosinophils and basophils, constitute a group of ... Neutrophil, type of white blood cell (leukocyte) that is characterized histologically by its ability to be stained by neutral ... More About Neutrophil. 9 references found in Britannica articles. Assorted References. *major reference* In blood: Neutrophils ... blood: Neutrophils. The neutrophils are fairly uniform in size with a diameter between 12 and 15 μm. The nucleus consists of ...
Neutrophils are a primary defense against bacterial infection. Neutrophils are made in the bone marrow (like all the cells of ... Neutrophils perform their function partially through phagocytosis, a process by which some cells ... Neutrophil Neutrophils are Leukocytes (white blood cells) of the Polymorphonuclear Leukocyte subgroup. Neutrophils form a ... However, neutrophils move out of blood vessels into infected tissue in order to attack the foreign substance ( allergen , ...
... whereas circulating neutrophils become activated tissue neutrophils. Extending this to the tumor microenvironment, recent ... Origins of tumor-associated macrophages and neutrophils. Virna Cortez-Retamozo, Martin Etzrodt, Andita Newton, Philipp J. Rauch ... Origins of tumor-associated macrophages and neutrophils. Virna Cortez-Retamozo, Martin Etzrodt, Andita Newton, Philipp J. Rauch ... D) Total number of monocytes and neutrophils retrieved from spleens of the same patients. (E) Fate of human Lin− cKit+ splenic ...
Tumor-infiltrating neutrophils in pancreatic neoplasia.. Reid MD1, Basturk O, Thirabanjasak D, Hruban RH, Klimstra DS, Bagci P ... components of these neoplasms did not have tumor-infiltrating neutrophils. Tumor-infiltrating neutrophils were not striking in ... 11 showed significant tumor-infiltrating neutrophils (mean, 25; range, 14-63 tumor-infiltrating neutrophils). Among intraductal ... In this study, the presence of tumor-infiltrating neutrophils within and/or adjacent to neoplastic cells was investigated in ...
Berger, M., OShea, J., Cross, A. S., Folks, T. M., Chused, T. M., Brown, E. J., and Frank, M. M., 1984, Human neutrophils ... Katz, J. D., Rimmemran, C. M., Berrettoni, C. M., and Hafeman, D. G., 1987, Receptors for C3b on the neutrophil surface ... Richerson, H. B., Walsh, G. M., Walport, M. J., Moqbel, R., and Kay, A. B., 1985, Enhancement of human neutrophil complement ... Jack, R. M., and Fearon, D. T., 1984, Altered surface distribution of both C3b receptors and Fc receptors on neutrophils ...
Neutrophils are among the first responders at sites of infection and are an essential arm of the innate immune system. They ... Neutrophils isolated from the lungs of mice 5 weeks after infection with Mycobacterium tuberculosis produced large amounts of ... When neutrophils were depleted from these mice, proinflammatory dendritic cells and cytokines became more abundant in the lung ... M. A. Cassatella, M. Locati, A. Mantovani, Never underestimate the power of a neutrophil. Immunity 31, 698-700 (2009). [Online ...
Your body is a walking miracle. At any given time, at the cellular level, your body is fighting a very real war - a war against infections, bacteria and unwanted microorganisms. But what if you are an unknown carrier of a genetic disorder that disables certain white blood cells, called phagocytes, from responding properly? These […]. ...
These contain proteins that enable the neutrophil to deliver lethal hits against microorganisms, but also to cause great tissue ... Neutrophils are produced in the bone marrow from stem cells that proliferate and differentiate to mature neutrophils fully ... Neutrophils are produced in the bone marrow from stem cells that proliferate and differentiate to mature neutrophils fully ... Neutrophils circulate in the blood as dormant cells. At sites of infection, endothelial cells capture bypassing neutrophils and ...
... neutrophils) defend our brains from infection -- they move the microbes from our brains blood vessels or vasculature so they ... Neutrophils vacuum microbes away from the brain New research published in the Journal of Leukocyte Biology suggests that ... "These new studies that demonstrate the ability to neutrophils to move dangerous germs away from the brain makes us rethink the ... Real-time in vivo imaging reveals the ability of neutrophils to remove Cryptococcus neoformans directly from the brain ...
This should be an interesting line of future neutrophil research.. Neutrophils are potent regulators of inflammation via the ... Recent findings on the mechanisms for neutrophil recruitment to the tumor, for neutrophils supporting tumor progression, and ... Once at sites of infection, neutrophils actively phagocytose microorganisms or form neutrophil extracellular traps (NETs) to ... they can also form neutrophil extracellular traps (NETs) to kill microbes. NETs are fibers composed of chromatin and neutrophil ...
describe a dynamic system model of neutrophil bactericidal activity that confirms and extends the concept of critical ... The authors demonstrate that when the neutrophil concentration approaches the critical concentration, bacterial populations in ... Their experimental findings raise the intriguing possibility of greater variability in bactericidal activity of neutrophils ...
... destruction of neutrophils in the bloodstream and hereditary diseases, such as congenital... ... Causes of low levels of neutrophils include the reduction of neutrophil production in the bone marrow, ... Neutrophils are cells that protect the body from infections. Low levels of neutrophils, called neutropenia, mean that the body ... Causes of low levels of neutrophils include the reduction of neutrophil production in the bone marrow, destruction of ...
Activities of the neutrophil polymorph.. Br Med J 1972; 2 doi: (Published 13 May 1972) ...
Neutrophils may be subdivided into segmented neutrophils and banded neutrophils (or bands). They form part of the ... Normally, neutrophils contain a nucleus divided into 2-5 lobes. Neutrophils are a type of phagocyte and are normally found in ... Neutrophils will show increasing segmentation (many segments of the nucleus) as they mature. A normal neutrophil should have 3- ... Though neutrophils can kill many microbes, the interaction of neutrophils with microbes and molecules produced by microbes ...
Neutrophils, segmented - Neutrophils are the larger and physiologically most numerous class of infection-fighting white blood ... so a high segmented neutrophil count implies vigorous response, is clearly explained in Medindia s glossary of medical terms ... Medical Word - Neutrophils, segmented. Ans : Neutrophils are the larger and physiologically most numerous class of infection- ... Neutrophils, segmented - Glossary. Written & Compiled by Medindia Content Team. Medically Reviewed by The Medindia Medical ...
... neutrophils gained the ability to migrate to MKYMYm; however, this was lost when the wild-type neutrophils were blocked from ... a chemokine that induces comparatively little LTB4 secretion from neutrophils. Mouse neutrophils deficient in either BLT1 or an ... Neutrophils are the first responders to sites of infection and inflammation, and they are recruited from the blood by primary ... Together, these data suggest that the secretion of LTB4 by neutrophils migrating to fMLP acts as a second gradient to increase ...
Neutrophils from 90 days-old rats showed a decrease in phagocytic and fungicidal capacity, without change in cellular viability ... The aim of the present study was to evaluate the function of neutrophils submitted to in vivo lower and higher concentration of ... In conclusion, our data suggest that increase in testosterone levels induced significant alteration in neutrophil function, ... Using different approaches we evaluated cell viability and function and gene expression in rat neutrophils from 60 and 90 days- ...
... then sent home but cant remember the neutrophils. I know when my WBC went to 2.8, my neutrophils were 11 so I can imagine they ... My neutrophils have dropped extremly low before, but I know this was because of Cytoxan. I know my WBC was .08 and I know the ... My doctor hasnt commented on the low neutrophils yet. I figure that hed call me in if he was worried about it. I figure that ... But as for the Neutrophils, I hope that it goes up, not down, thats for sure. Thanks for the link too...I checked it out and ...
  • The force of attraction that determines the direction in which neutrophils will move is known as chemotaxis and is attributed to substances liberated at sites of tissue damage. (
  • Chemotaxis, the directional movement of the cell guided by extracellular chemoattractant gradients, plays an essential role in the recruitment of neutrophils to sites of inflammation. (
  • The article by X. Xu and T. Jin describes the novel functions of the PLC/PKC/PKD signaling axis in GPCR-mediated chemotaxis of neutrophils. (
  • For example, fMLF gradients around bacterial targets are assumed to elicit rapid and directional chemotaxis of neutrophils in the close vicinity of the source 1 . (
  • Chemotaxis of immature vs. mature neutrophils. (
  • However, during the acute phase of inflammation , particularly as a result of bacterial infection , neutrophils leave the vasculature and migrate toward the site of inflammation in a process called chemotaxis . (
  • Neutrophils undergo a process called chemotaxis that allows them to migrate toward sites of infection or inflammation. (
  • Inhibits C5a-dependent neutrophil enzyme release and chemotaxis. (
  • Our microfluidic model suggests a new paradigm for neutrophil accumulation at sites of inflammation, which depends on the balance of three simultaneous processes: chemotaxis along diffusion gradients, retrotaxis following mechanical guides, and stopping triggered by phagocytosis. (
  • Once at sites of infection, neutrophils actively phagocytose microorganisms or form neutrophil extracellular traps (NETs) to trap and kill pathogens. (
  • Part V provides multiple assays for measuring production of intracellular and/or extracellular reactive oxygen species, and a method that details use of the cell-free NADPH oxidase assay, an iconic assay for studies of the neutrophil NADPH oxidase. (
  • Part VI provides chapters that describe how to analyze formation and function of neutrophil extracellular traps. (
  • Here, we describe that, upon activation, neutrophils release granule proteins and chromatin that together form extracellular fibers that bind Gram-positive and -negative bacteria. (
  • These neutrophil extracellular traps (NETs) degrade virulence factors and kill bacteria. (
  • Neutrophils also degranulate, releasing antimicrobial factors into the extracellular medium ( 3 ). (
  • Here, we show that neutrophils generate extracellular fibers, or neutrophil extracellular traps (NETs), which are structures composed of granule and nuclear constituents that disarm and kill bacteria extracellularly. (
  • Surprisingly, we found that activated neutrophils but not naïve cells made prominent extracellular structures (arrows, Fig. 1, B and D ). These fibers, or NETs, were very fragile, and specimens had to be washed and fixed carefully to preserve them. (
  • Neutrophils were activated with 10 ng of IL-8 for 30 min and stained for neutrophil elastase ( A ), DNA ( B ), and the complex formed by H2A-H2B-DNA ( C ). Extracellular fibrous material is stained brightly. (
  • These DNA snares are called neutrophil extracellular traps or NETs. (
  • Neutrophils are white blood cells that use their own DNA snares called neutrophil extracellular traps (NETs) as a last line of defense against pathogens. (
  • Additionally, we show that OPA1-dependent ATP production in these cells is required for microtubule network assembly and for the formation of neutrophil extracellular traps. (
  • Neutrophils release many toxic substances, such as reactive oxygen species, cytokines, and neutrophil extracellular traps (NETs), proteins that cage bacteria and damage tissue. (
  • Fluoride ion, at concentrations above 10 mM, has been found to activate a superoxide production response in human neutrophils which is strongly dependent on the presence of extracellular calcium. (
  • During inflammatory activation, neutrophils leave the blood, interact with extracellular matrix proteins, and migrate into tissues in response to chemotactic factors to phagocytose and kill infectious agents by using toxic granule contents and reactive oxygen metabolites. (
  • While neutrophil extracellular traps help guard the body from infection, they also can contribute to a range of diseases. (
  • When a neutrophil encounters a pathogen, it can respond in several ways: phagocytosis, degranulation, or by releasing neutrophil extracellular traps (NETs). (
  • Neutrophil granulocyte migrates from the blood vessel to the matrix, secreting proteolytic enzymes, in order to dissolve intercellular connections (to the improvement of its mobility) and envelop bacteria through phagocytosis. (
  • Phagocytosis is central to the microbicidal function of neutrophils. (
  • Neutrophils engulf bacteria (see phagocytosis ) and release various substances, such as lysozyme and oxidizing agents. (
  • Neutrophils perform their function partially through phagocytosis, a process by which they "eat" other cells and foreign substances. (
  • Egression from the bone marrow and blood stream, adhesion, migration, activation, phagocytosis and killing of pathogens describe the basic mechanisms associated with neutrophils. (
  • Phagocytosis of Gram-positive and Gram-negative bacteria by immature vs. mature neutrophils. (
  • Change in status of Neutrophil function (phagocytosis and oxidative burst) in subjects on AZD5069 and placebo [ Time Frame: Day -1, Day 1, Day 2, Day 3, Day 4 and 7 days after end of treatment. (
  • TNF-dependent phagocytosis, as measured indirectly by iodination, is inhibited by monoclonal antibodies (Mab) 60.1 and 60.3, which recognize different epitopes on the C3bi receptor/adherence-promoting surface glycoprotein of neutrophils. (
  • TNF may be a natural stimulant of neutrophils which promotes adherence to endothelial cells and to particles, leading to increased phagocytosis, respiratory burst activity, and degranulation. (
  • This amino acid has been shown to play a role in lymphocyte proliferation, cytokine production by lymphocytes and macrophages and phagocytosis and superoxide production by macrophages and neutrophils. (
  • Scientists have shown for the first time that platelets, the cells needed for blood clotting, help white blood cells called neutrophils fight inflammation. (
  • To guard against rapid depletion of the short-lived neutrophil (for example, during infection), the bone marrow holds a large number of them in reserve to be mobilized in response to inflammation or infection. (
  • Neutrophils migrate to sites of inflammation and infection where they recognize and phagocytose invading microorganisms, in order to kill them via different cytotoxic mechanisms. (
  • In recent years, it has become evident that neutrophils not only have a fundamental role in the acute phase of inflammation when they actively eliminate pathogens, but also are capable of modifying the overall immune response. (
  • To illuminate the complex role of neutrophils in infection, inflammation, and immunity, this special issue has gathered original and review articles that will help us expand our knowledge on neutrophil biology. (
  • As stated before, any neutrophil response begins with migration of these leukocytes to the site of infection or inflammation. (
  • Neutrophils are the first responders to sites of infection and inflammation, and they are recruited from the blood by primary chemoattractants such as the bacterial formyl peptide fMLP. (
  • Noting that the secondary chemoattractant leukotriene B 4 (LTB 4 ), a metabolite of arachidonic acid (AA), is thought to be secreted by neutrophils upon reaching the site of inflammation, Afonso et al . (
  • Abnormal aspects of host response, such as lack of fever, local inflammation or pus, should immediately alert the clinician to the possibility of a neutrophil defect. (
  • [2] Neutrophils are more associated with acute inflammatory response than macrophages , which are more involved in chronic inflammation. (
  • Simulations suggest that a systemic inflammation leads to functionally heterogeneous neutrophil subsets. (
  • Among the most original findings presented in this publication figure the observations that neutrophils cause increased vascular permeability during acute inflammation, regulate directly the angiogenic process, and influence tumor development. (
  • Neutrophils react within an hour of tissue injury and are the hallmark of acute inflammation. (
  • However, because neutrophil antimicrobial products can also damage host tissues , other authorities feel that their short life is an adaptation to limit damage to the host during inflammation . (
  • Neutrophils are the first immune cells recruited to the site of inflammation, and their action is crucial to limit invasion by microorganisms. (
  • Neutrophils in Post-myocardial Infarction Inflammation: Damage vs. Resolution? (
  • Neutrophil depletion in experimental MI results in impaired resolution of inflammation and uncoordinated fibrotic scar formation, which translates into adverse remodeling and decreased cardiac function ( 9 ). (
  • These findings therefore suggest that an increased amount of SIRPα on the surface of activated neutrophils could serve to negatively fine-tune neutrophil accumulation in inflammation. (
  • This way, SIRPα can negatively fine-tune neutrophil migration and accumulation in inflammation. (
  • They are formed from stem cells in the bone marrow and differentiated into subpopulations of neutrophil-killers and neutrophil-cagers. (
  • Neutrophils are produced in the bone marrow and released into the bloodstream to travel to wherever they are needed. (
  • Large numbers of immature forms of neutrophils, called neutrophilic band cells, are produced by the bone marrow when the demand is high. (
  • Here we describe the isolation of bone marrow, peripheral blood, and lung airspace and interstitial neutrophil populations, using density gradient separation, lavage, and flow cytometry techniques. (
  • The bone marrow of a normal adult produces about 100 billion neutrophils daily. (
  • Like all the cells of the immune system , neutrophils are produced in the bone marrow and circulate in the bloodstream. (
  • Granulocyte/macrophage progenitors (GMPs), for example, are clonogenic bone marrow cells that descend from HSCs and commit to either neutrophils or monocytes. (
  • Causes of low levels of neutrophils include the reduction of neutrophil production in the bone marrow, destruction of neutrophils in the bloodstream and hereditary diseases, such as congenital agranulocytosis, states Medical News Today. (
  • Infections like tuberculosis, viral hepatitis, HIV and folic acid deficiency can affect the bone marrow, causing a reduced production of neutrophils. (
  • Leukaemia is a type of cancer which begins in bone-marrow cells and then spreads to affect other cells in the body including neutrophils, a type of white blood cell which is responsible for attacking blood-borne bacteria. (
  • Neutropenia results from damage to the bone marrow or depletion or destruction of neutrophils by drugs, diseases, or congenital disorders that block neutrophil differentiation. (
  • Band neutrophils are immature cells, released by the bone marrow in response to demand. (
  • While the role of neutrophils has been studied in different animal models of IBD for many years, their contribution to the pathogenesis of IBD remains poorly understood, and no molecules targeting neutrophils are used and validated for the treatment of these pathologies. (
  • Wéra O, Lancellotti P, Oury C. The Dual Role of Neutrophils in Inflammatory Bowel Diseases. (
  • Role of Neutrophils in Cystic Fibrosis Lung Disease, Role of Neutrophils in Disease Pathogenesis Maitham Khajah, IntechOpen, DOI: 10.5772/67798. (
  • Neutrophil Role in Periodontal Disease, Role of Neutrophils in Disease Pathogenesis Maitham Abbas Khajah, IntechOpen, DOI: 10.5772/67789. (
  • You should also take steps to stay healthy and avoid germs or bacteria, as you will be more susceptible to catching an infection or illness when your neutrophil levels are low. (
  • However, neutrophils move out of blood vessels into infected tissue in order to attack the foreign substance ( allergen , bacteria, etc. (
  • investigated the responses of mouse neutrophils to bacteria and various agonists of pattern-recognition receptors, such as Toll-like receptors (TLRs) and C-type lectin receptors (CLRs). (
  • Exposure of neutrophils to bacteria resulted in the production of much greater amounts of IL-10, which led the authors to investigate which other signals might synergize with TLR agonists in IL-10 production. (
  • Coactivation of TLR2 and the CLR Dectin-1, which recognizes carbohydrate moieties on bacteria and fungi, stimulated neutrophils to produce large quantities of IL-10, an effect that depended on MyD88 (an adaptor protein that is part of the TLR2 pathway) and the tyrosine kinase Syk, which mediates CLR-dependent responses. (
  • When neutrophils were depleted from these mice, proinflammatory dendritic cells and cytokines became more abundant in the lung and the number of bacteria was substantially reduced. (
  • X. Zhang, L. Majlessi, E. Deriaud, C. Leclerc, R. Lo-Man, Coactivation of Syk kinase and MyD88 adaptor protein pathways by bacteria promotes regulatory properties of neutrophils. (
  • found that the capacity of neutrophils to engulf bacteria is reduced when simple sugars like glucose, fructose as well as sucrose, honey and orange juice were ingested, while the ingestion of starches had no effect. (
  • Fasting, on the other hand, strengthened the neutrophils' phagocytic capacity to engulf bacteria. (
  • Polymorphonuclear neutrophils (PMNs) are the most abundant leukocytes in the blood and constitute the first line of host defense against numerous infectious pathogens, including bacteria, fungi, and protozoa. (
  • Most complications that occur following low levels of neutrophils are due to bacteria that mainly live in the urinary tract or on the skin, notes MedicineNet. (
  • Engulfing of bacteria by neutrophils is accompanied by the consumption of large amounts of oxygen, a so-called respiratory burst. (
  • Neutrophils engulf and kill bacteria when their antimicrobial granules fuse with the phagosome. (
  • In response to inflammatory stimuli, neutrophils migrate from the circulating blood to infected tissues, where they efficiently bind, engulf, and inactivate bacteria. (
  • I know neutrophils fight bacteria. (
  • Neutrophils are phagocytes and constitute the most numerous and important effector cells of the innate immune system, especially in the defence against bacteria and fungi. (
  • Neutrophils engulf bacteria and cellular debris. (
  • Model parameters were optimized to reproduce key serum cytokine (TNF-a, IL1, IL10, IL6) time courses and neutrophil/bacteria counts for each compartment during sublethal and lethal sepsis in bacteria-induced or lipopolysaccharide-induced rodent experimental models. (
  • In these cases, the bacteria replicate to high numbers, and inflammatory mediators call in neutrophils to reinforce the defenses. (
  • However, the method by which neutrophils kill the pneumococcus as well as other Gram-positive bacteria, is not fully understood. (
  • neutrophil A type of white blood cell ( leucocyte ) that has a lobed nucleus and granular cytoplasm (see granulocyte ). (
  • A neutrophil is a type of white blood cell, a type of granulocyte, and a type of phagocyte. (
  • In this issue of Blood , Bartels and colleagues demonstrate that acetylation of the transcription factor CCAAT enhancer binding protein ε (C/EBPε) is essential for terminal neutrophil granulocyte differentiation. (
  • 2 Prophylactic use of granulocyte colony-stimulating factor (G-CSF) reduces mortality by increasing neutrophil numbers. (
  • 3 C/EBPβ-deficient mice display normal granulocyte differentiation and steady-state levels of neutrophils but are unable to produce neutrophils in response to cytokine exposure or infection during "emergency" granulopoiesis. (
  • The cytokine granulocyte-macrophage colony-stimulating factor ( GM-CSF ) causes differentiation into the neutrophils, with maturation to polymorphonuclear neutrophils via juvenile and band forms. (
  • The neutrophil granulocyte is activated through recognition of target molecules, viz the many different surface receptors the neutrophil expresses, some of which bind molecules that are unique to pathogens [8] such as peptidoglycan , a component of bacterial cell walls. (
  • The neutrophil granulocyte is a phagocyte , capable of ingesting and lysing many pathogens. (
  • You may develop low levels of neutrophils, called neutropenia, if you have cancer or are undergoing treatment for cancer, such as chemotherapy. (
  • Neutropenia is the term for low neutrophil levels. (
  • Neutropenia, or a low neutrophil count, can last for a few weeks or it can be chronic. (
  • An abnormally low number of neutrophils is called neutropenia . (
  • Low levels of neutrophils, called neutropenia, mean that the body cannot fight against bacterial infections, reports Healthline. (
  • Chronic neutropenia often accompanies HIV infection, the result of impaired production of neutrophils and accelerated destruction of neutrophils by antibodies (see Ch. 145). (
  • In three weeks, she hopes I'll be healthy enough to get a base line neutrophil count to see if I have naturally occuring neutropenia. (
  • Neutropenia is an abnormal drop in the blood neutrophil count, which may be due to drugs, infections, blood disorders, cancer, or birth defects. (
  • Leukaemia and leukaemia treatments (such as chemotherapy) can cause low neutrophil counts, a condition known as neutropenia. (
  • The National Neutropenia Network classifies mild neutropenia as being characterised by neutrophil levels between 1000 per mm3 and 1500 per mm3. (
  • Moderate neutropenia is characterised by neutrophil levels between 500 per mm3 and 999 per mm3. (
  • Severe neutropenia is characterised by neutrophil levels which are lower than 500 per mm3. (
  • According to The National Neutropenia Network, the risk of infection increases as neutrophil levels decrease. (
  • 2 A better understanding of the mechanisms that regulate granulopoiesis and terminal neutrophil differentiation could spur development of new strategies to overcome neutropenia and improve clinical outcomes. (
  • But new evidence, which may lead to better drugs to fight deadly pathogens, indicates that neutrophils might actually distinguish among their targets. (
  • Together, these data suggest that neutrophils can respond to pathogens by producing IL-10 to modulate the inflammatory response. (
  • Neutrophils are the first leukocytes to migrate from the blood to injured or infected sites for killing pathogens and removing cellular debris. (
  • Apart from the innate ability to recognize potential pathogens, the neutrophil is also able to be activated by target-bound opsonins ( antibodies ), thus making the neutrophil a humoral effector cell. (
  • In order to facilitate the lysis of ingested pathogens, the neutrophil synthesizes strong oxidants in what has been termed the respiratory burst, though it does not involve respiration. (
  • In the past, neutrophils were often reduced to their ability to release preformed mediators and kill pathogens. (
  • Some experts feel that the short lifetime of neutrophils is an evolutionary adaptation to minimize propagation of those pathogens that parasitize phagocytes. (
  • The primary function of neutrophils in host defense is to contain and eradicate invading microbial pathogens. (
  • Neutrophils are the most abundant circulating leukocytes in humans and are essential for the defense against invading pathogens. (
  • Our findings show that Gram-positive pathogens are killed by human neutrophils via different mechanisms involving serine proteases. (
  • Neutrophils are a type of white blood cell that is responsible for much of the body's protection against infection. (
  • Neutrophils are a type of white blood cell that helps your body fight infection. (
  • You're at greatest risk of infection if your neutrophil count drops below 1,500 neutrophils per microliter. (
  • If your neutrophil counts are high, it can mean you have an infection or are under a lot of stress. (
  • Within the body the neutrophils migrate to areas of infection or tissue injury. (
  • Neutrophils form a primary defense against bacterial infection. (
  • Normally a serious bacterial infection causes the body to produce an increased number of neutrophils, resulting in a higher than normal WBC count . (
  • Macrophages and neutrophils participate in defense mechanisms that protect the host against injury and infection. (
  • Neutrophils are among the first responders at sites of infection and are an essential arm of the innate immune system. (
  • Neutrophils isolated from the lungs of mice 5 weeks after infection with Mycobacterium tuberculosis produced large amounts of IL-10. (
  • Researchers from the University of Maryland, College Park, and Nanjing Medical University, China, have discovered a new way that white blood cells (neutrophils) defend our brains from infection--they move the microbes from our brains' blood vessels or vasculature so they can be disposed elsewhere instead of just killing them at the site of infection. (
  • Neutrophils, the most abundant white cells in humans, serve as the primary cellular defense against infection. (
  • Neutrophils help fight infection by ingesting microorganisms and releasing enzymes that kill the microorganisms. (
  • Numbers of neutrophils can go down after or during a viral infection because many of the neutrophils leave the blood to fight the infection in the tissues and so normal blood values are reduced. (
  • In a viral infection, the role of the neutrophils is mostly to clean up the cellular debris, AFAIK. (
  • Influenza-infected mouse trachea: virus (green), neutrophils (red), collagen (blue) UNIVERSITY OF ROCHESTER, KIHONG LIM Part of the innate immune system, white blood cells called neutrophils circulate in the blood and are the first responders to an influenza respiratory infection, guiding T cells-part of the adaptive immune response-to the site. (
  • Neutrophils create a physical trail of chemokines that allow T cells to home in on the infection site, according to a study published today (September 3) in Science . (
  • In the current study, the researchers find that neutrophils are the first-responder cells, appearing in the trachea at infection day three or four. (
  • Yet these T cells did not efficiently home to the virus-infected epithelial cells of the trachea, and cleared their infection less efficiently, suggesting that an early-mounted neutrophil response in necessary for T cells to reach the infection site. (
  • Neutropenic sepsis is a potentially life-threatening condition when a patient with low neutrophil counts develops an infection that spirals out of control if not treated urgently and is usually seen in cancer patients on chemotherapy. (
  • Patients with low neutrophil levels for three or more days are at a greater risk of developing an infection such as a fungal infection, ear infection or tonsillitis. (
  • The rate of growth of Listeria monocytogenes in the livers of mice infected intravenously with a lethal or sublethal inoculum of this facultative intracellular bacterium is greatly increased if neutrophils and other host cells are prevented from accumulating at foci of infection during the first 24 h by treatment with a monoclonal antibody (5C6) specific for the type 3 complement receptor of myelomonocytic cells. (
  • In this way, neutrophils serve to break the chain of cell-to-cell spread of infection. (
  • When nearing the site of infection, the neutrophil will attach repeatedly to the endothelial blood vessel lining viz. (
  • Because of their relative abundance compared to other leukocytes, neutrophil granulocytes are often the first to arrive at sites of new infection. (
  • Adequate recruitment of neutrophils to sites of infection is one of the early and important events of the innate immune response. (
  • Simulations support that the positive effect of HA could be ascribed partly to reducing circulating levels of inflammatory effectors, thus reducing lung endothelial activation and promoting neutrophil recruitment to the primary site of infection, resulting in improved clearance of infection. (
  • Being highly motile, neutrophils quickly congregate at a focus of infection , attracted by cytokines expressed by activated endothelium , mast cells and macrophages . (
  • In support of this beneficial role for neutrophils during tissue repair, there is also evidence for anti-inflammatory and reparative properties of neutrophils in other, non-cardiovascular inflammatory conditions, including bacterial infection and non-sterile injury. (
  • Neutrophils, or polymorphonuclear leukocytes, comprise a crucial component of innate immunity, controlling bacterial and fungal infection through a combination of both oxidative and nonoxidative mechanisms. (
  • Indeed, neutrophils are believed to play an important role in controlling infection caused by the major human pathogen Streptococcus pneumoniae . (
  • Infiltration of neutrophils into CT26 tumors after bacterial infection. (
  • Neutrophils were depleted by triple i.p. injections of 25 or 100 μg anti-Gr1, respectively, 1 d before (−1), simultaneously (0), and 1 d after (1) infection. (
  • 1982). In addition, the human neutrophil CR1 mediates endocytosis of soluble multivalent ligand or soluble C3b-bearing complexes (Fearon et al . (
  • Up to 17% of female human neutrophil nuclei has a drumstick-shaped appendage which contains the inactivated X chromosome. (
  • Human neutrophil collagenase. (
  • 3 Interestingly, mutations in the CEBPE gene account for some cases of human neutrophil-specific granule disease, a rare congenital disorder, characterized by increased circulating, immature neutrophils, and recurrent pyogenic infections. (
  • A human neutrophil interacting with Klebsiella pneumoniae (pink), a multidrug-resistant bacterium that causes severe hospital infections. (
  • Here, we designed a microfluidic platform inside which we observed human neutrophil migration in response to chemoattractant sources inside channels, simulating the biochemical and mechanical confinement conditions at sites of injury in tissues. (
  • We investigated human neutrophil killing of the pneumococcus in a complement-dependent opsonophagocytic assay. (
  • Neutrophils are key cellular components of the innate immune response and characteristically migrate from the blood towards and throughout tissues. (
  • Thus, neutrophils must integrate all signals to migrate effectively. (
  • The neutrophil is able to chemotactically migrate to infected tissue, moving upstream against a concentration gradient of Interleukin-6, [7] secreted by activated endothelial cells , mast cells and macrophages . (
  • When the neutrophil has been slowed down enough, it will migrate from the blood vessel lumen to the infected tissue via an integrin -mediated pathway. (
  • While primed blood neutrophils migrate to the infectious site and become activated locally in tissue, systemically activated blood neutrophils, which have fewer essential chemokine receptors, have impaired ability to migrate. (
  • We observed that, after initially following the direction of chemoattractant gradients, more than 90% of human neutrophils can reverse their direction and migrate persistently and for distances longer than one thousand micrometers away from chemoattractant sources (retrotaxis). (
  • Ubags N.D.J., Suratt B.T. (2018) Isolation and Characterization of Mouse Neutrophils. (
  • Syk- and MyD88-dependent signaling pathways converge to endow mouse neutrophils with regulatory properties. (
  • Mouse neutrophils deficient in either BLT1 or an LTB 4 -generating enzyme migrated poorly to MKYMYm, a synthetic agonist of the fMLP receptor (FPR1). (
  • To test this, the researchers inhibited the cell cycle proteins in mouse neutrophils, and found that indeed, fewer NETs were released. (
  • They identified them by staining for Ly6G, a cell-surface receptor specific for mouse neutrophils. (
  • Our understanding of the origins of tissue macrophages and neutrophils, going back to self-renewing hematopoietic stem cells (HSCs), is largely based on studies not involving cancer ( 10 ⇓ ⇓ - 13 ). (
  • Circulating monocytes become tissue macrophages (or dendritic cells), whereas circulating neutrophils become activated tissue neutrophils. (
  • How neutrophils integrate the various signals in the tissue microenvironment and mount effective responses is not fully understood. (
  • Neutrophil sequestration may occur after viral tissue damage. (
  • When influenza invades the mouse respiratory tract, neutrophils guide the subsequent T-cell attack on infected tissue, scientists show. (
  • Once a neutrophil is induced to release its NETs, it anchors itself in the tissue and breaks down its nuclear envelope: the barrier between the nuclear DNA and the rest of the cell. (
  • Systemically activated neutrophils cause impairment of neutrophil migration to the tissue, and systemic neutrophil activation favors blood neutrophils sequestration in the lung. (
  • The results highlight the importance of peripheral innate immunity in Alzheimer's, and hint that neutrophils might be one source of tissue damage. (
  • Few researchers have focused on neutrophils, perhaps because these cells live for only hours and would be unlikely to accumulate in tissue. (
  • The authors detected NETs and the pro-inflammatory cytokine IL-17 around neutrophils in brain tissue, hinting that the phagocytes might be wreaking havoc. (
  • When these processes are not tightly regulated, they can trigger positive feedback amplification loops that promote neutrophil activation, leading to significant tissue damage and evolution toward chronic disease. (
  • Subsequently, blood monocyte-derived macrophages infiltrate the infarct area to remove cardiac tissue debris and apoptotic neutrophils, which, in turn activates reparative pathways necessary for scar formation ( 1 ). (
  • Neutrophil granulocytes constitute the front line of defense in the innate immune response to invading microorganisms, but can also contribute to development of inflammatory disease and tissue destruction following e.g. myocardial infarction or stroke. (
  • Middle and right, higher magnifications of the neutrophil border between viable and necrotic tumor tissue. (
  • We analyzed neutrophil gelatinase-associated lipocalin (NGAL) and seven other urine biomarkers to evaluate their usefulness in the diagnosis of UTI in infants.Eight urine biomarkers were analyzed in 108 infants with UTI. (
  • Journal of Critical Care found that a new bedside blood test for a blood biomarker called neutrophil gelatinase-associated lipocalin (NGAL) offered the promise of rapidly assessing if a critically ill patient is suffering from AKI. (
  • The present volume of Chemical Immunology and Allergy, however, offers a very broad and timely view by highlighting the versatile functions of neutrophils in inflammatory, immune and antitumoral responses. (
  • Basic science research is being performed in the fields of NK cells, T cell function in atopic dermatitis, HIV, neutrophil biology, DiGeorge syndrome, and other fields in basic immunology as described above. (
  • Having a high percentage of neutrophils in your blood is called neutrophilia. (
  • More important than the percentage of neutrophils is the absolute neutrophil count (ANC), which should fall between 1.0 to 8.0 k/ul. (
  • The reason the ANC represents the true clinical picture better than the percentage of neutrophils is that, in cases where blood counts are suppressed by therapy, the percentage of neutrophils will be higher when the overall counts are low. (
  • One may calculate the ANC by multiplying the percentage of neutrophils (in decimal form) plus the percentage of bands (in decimal form) by the total number of white blood cells. (
  • So, if your percentage of neutrophils is low normal, and your wbc count is low normal, then your ANC could easily be below normal. (
  • They found that a therapeutic strategy aimed at enhancing the accumulation of neutrophils could help prevent cryptococcal meningoencephalitis. (
  • A histological examination of the livers of control mice showed that the accumulation of neutrophils at infectious foci resulted in the focal destruction of infected hepatocytes. (
  • Mounting evidence shows that severe sepsis is characterized by impaired neutrophil migration to the primary infectious inflammatory site and deleterious accumulation of neutrophils in distant organs, resulting in organ dysfunction and death. (
  • There is strong evidence that non-specific adsorption of circulatory cytokines (hemadsorption[HA]) decreases lung accumulation of neutrophils and improves outcome, but the underlying mechanisms remain elusive. (
  • In mice expressing a mutated form of SIRPα, where the cytoplasmic signaling domain was deleted, we found an enhanced accumulation of neutrophils in the peritoneal cavity in a peritonitis model. (
  • It is the goal of this proposal to study the fate and the innate immune functions of immature neutrophils obtained in patients with early septic shock. (
  • Immature neutrophils will be separated from mature neutrophils. (
  • 5% immature neutrophils. (
  • Surface expression of receptors of the innate immunity in immature vs. mature neutrophils. (
  • Production by immature vs. mature neutrophils of inflammatory mediators and reactive oxygen species in response to bacterial agonists. (
  • Ex vivo viability and resistance to apoptosis of immature vs. mature neutrophils. (
  • there may be an additional 0 to 3 percent of immature band neutrophils. (
  • Immature forms of neutrophil are juvenile and band . (
  • Although we do not yet understand the molecular mechanisms that mediate this transmigration process, the last years witnessed the discovery of the first neutrophil and epithelial cell surface proteins critically involved in transepithelial migration of neutrophils. (
  • investigated whether LTB 4 might instead play a role during neutrophil migration. (
  • In a transwell assay, blocking LTB 4 production or signaling inhibited migration of neutrophils to fMLP, but not to interleukin-8, a chemokine that induces comparatively little LTB 4 secretion from neutrophils. (
  • Together, these data suggest that the secretion of LTB 4 by neutrophils migrating to fMLP acts as a second gradient to increase selective fMLP-dependent signaling and enhance migration. (
  • Neutrophils following a gradient of primary chemoattractant secrete leukotriene B 4 , generating a secondary gradient that enhances migration. (
  • Here, we employed microfluidic mazes that replicate features of interstitial spaces and chemoattractant gradients within tissues to analyze the migration patterns of human neutrophils. (
  • We find that neutrophils respond to LTB4 and fMLF gradients with highly directional migration patterns and converge towards the source of chemoattractant. (
  • Moreover, neutrophils respond to gradients of C5a and IL-8 with a low-directionality migration pattern and disperse within mazes. (
  • Inhibitors of MAP kinase and PI-3 kinase signaling pathways do not alter either convergent or divergent migration patterns, but reduce the number of responding neutrophils. (
  • Overlapping gradients of chemoattractants conserve the convergent and divergent migration patterns corresponding to each chemoattractant and have additive effects on the number of neutrophils migrating. (
  • These results suggest that convergent and divergent neutrophil migration-patterns are the result of simultaneous activation of multiple signaling pathways. (
  • The team next identified CXCL12, a neutrophil-produced chemokine that could induce T-cell migration in vivo. (
  • In order to capture impaired recruitment of neutrophil in severe sepsis, several lines of evidence about the mechanisms influencing neutrophil migration in sepsis were reviewed and incorporated in the model. (
  • Herein, we review the mechanisms involved in the physiologic process of neutrophil transepithelial migration, including the role of specific adhesion molecules on the leukocyte and epithelial cells. (
  • The current paradigm of unidirectional migration of neutrophils from circulation to sites of injury in tissues has been recently challenged by observations in zebrafish showing that neutrophils can return from tissues back into the circulation. (
  • However, the relevance of these observations to human neutrophils remains unclear, the forward and reverse migration of neutrophils is difficult to quantify, and the precise conditions modulating the reverse migration cannot be isolated. (
  • The aim of the present thesis was to investigate neutrophil SIRPα expression in response to inflammatory activation or apoptosis, and how this receptor can regulate neutrophil adhesion and cell migration. (
  • NETs contained proteins from azurophilic (primary) granules ( 5 , 6 ) such as neutrophil elastase ( Fig. 2A ), cathepsin G, and myeloperoxidase (table S1). (
  • DNA binds neutrophil elastase and. (
  • All three compounds inhibited intracellular activity of the three major neutrophil serine proteases: elastase, cathepsin G, and proteinase 3. (
  • In NET release, shown here, the enzyme complex NADPH oxidase generates reactive oxide species (ROS), which in turn initiate the disintegration of granules, releasing neutrophil elastase (NE). (
  • The stated normal range for human blood counts varies between laboratories, but a neutrophil count of 2.5-7.5 x 10 9 /L is a standard normal range. (
  • Very low neutrophil counts can lead to life-threatening infections. (
  • If abnormal neutrophil counts are due to an underlying condition, your outlook and treatment will be determined by that condition. (
  • I've had two blood tests showing very low neutrophil counts (700 followed by 439) despite all other counts being normal. (
  • Mice with CXCL12-depleted neutrophils had fewer T cells within the infected trachea and had a slower clearance of the virus, similar to the mice with reduced neutrophil counts. (
  • SCN1 is a disorder of hematopoiesis characterized by a maturation arrest of granulopoiesis at the level of promyelocytes with peripheral blood absolute neutrophil counts below 0.5 x 10(9)/l and early onset of severe bacterial infections. (
  • Sixty paired venous and capillary total neutrophil counts (TNCs) were obtained from 30 healthy, term neonates on days 1 and 2 of life. (
  • When adhered to a surface, neutrophil granulocytes have an average diameter of 12-15 micrometers (µm) in peripheral blood smears . (
  • Neutrophil granulocytes have an average volume of 330 femtoliters (fl) and a diameter of 12-15 micrometers (µm) in peripheral blood smears . (
  • Several microbicidal functions of neutrophils involve the activation of the NADPH oxidase complex for production of reactive oxygen species (ROS) to mediate pathogen killing. (
  • We tested the hypothesis that changes reported on functions of neutrophils from streptozotocin-induced diabetic rats involve autophagy impairment. (
  • Lymphocytes, macrophages and neutrophils play an important role in the immune and inflammatory response. (
  • The metabolic fate of glutamine in lymphocytes, macrophages and neutrophils will be discussed in the present paper. (
  • describe that although N-formyl-methionyl-leucyl-phenylalanine (fMLF) and Platelet Activating Factor (PAF) induce similar intracellular signaling profiles, only fMLF induces interleukin-8 (IL-8) release and NADPH oxidase activity in neutrophils. (
  • Neutrophils do not eat viruses, because they are unable to fight intracellular agents. (
  • Neutrophil-mediated dissolution of infected host cells as a defense strategy against a facultative intracellular bacterium. (
  • In an attempt to further explore the calcium requirement of fluoride-induced neutrophil activation, intracellular calcium concentrations were monitored through use of the fluorescent calcium probe, Quin 2. (
  • When neutrophil granule proteases were inhibited with either a protease mixture, or specific serine protease inhibitors 4-(2-Aminoethyl)benzenesulfonylfluoride and diisopropylfluorophosphate, killing by neutrophils was inhibited in a manner that correlated with increased intracellular survival. (
  • Signal regulatory protein alpha (SIRPα) is a surface glycoprotein with two intracellular immunoreceptor-tyrosine-based inhibitory motifs (ITIMs), which is highly expressed in neutrophils and other myeloid cells. (
  • explains how the small monomeric GTPases of the Arf family and their guanine exchange factors (GEFs) and GTPase activating proteins (GAPs) participate in GPCR signaling cascades regulating several neutrophil functional responses. (
  • Zychlinsky, Amulic, and colleagues hypothesized that neutrophils were using the same cell cycle proteins used for cell division to release the NETs. (
  • Then, they observed human brains with fungal infections and confirmed that our neutrophils are also using cell cycle proteins. (
  • Acetylation on K121 and K198 is essential for terminal differentiation of neutrophils and expression of secondary granule proteins. (
  • Apart from phagocytic, oxidative lysis, the cytoplasm of the neutrophil contain many granulae, which contain soluble antimicrobial proteins, including lactoferrin , bactericidal/permeability increasing protein and defensins . (
  • The functional neutrophil response relies on exocytosis of cytoplasmic granules, each containing membrane proteins, which are thereby mobilized to the plasma membrane. (
  • It usually corresponds to a period of acute viremia and is related to virus-induced redistribution of neutrophils from the circulating to the marginal pool. (
  • An increase in the number of neutrophils occurs in acute infections, certain malignant neoplastic diseases, and some other disorders. (
  • Neutrophils contribute to lung injury in acute pneumococcal pneumonia. (
  • Traditionally, neutrophils have been merely considered as detrimental in the setting of an acute myocardial infarction. (
  • Neutrophil , type of white blood cell (leukocyte) that is characterized histologically by its ability to be stained by neutral dyes and functionally by its role in mediating immune responses against infectious microorganisms. (
  • Neutrophils are phagocytes, capable of ingesting microorganisms or particles. (
  • noun A neutrophil cell, especially an abundant type of granular white blood cell that is highly destructive of microorganisms. (
  • The results indicate that neutrophils play an important role in early defense against listeriosis in the liver by destroying infected hepatocytes, thereby reducing the opportunity for Listeria to multiply in permissive cells. (
  • Neutrophils, the most abundant granulocytes, are essential for host innate immune defense. (
  • We propose that dysregulated neutrophil trafficking in severe sepsis might be effectively explained by a mathematical model that incorporates the dynamic interactions of compartmentalized inflammatory responses. (
  • In this chapter, we discuss the current knowledge of the molecular mechanisms underlying phagosome formation and maturation in neutrophils. (
  • This process involves molecular mechanisms that coordinate cell polarization, delivery of receptors, and activation of integrins at the leading edge of neutrophils migrating toward chemoattractants. (
  • Further experimental studies about compartmental neutrophil populations are needed to clarify the relative contribution of these mechanisms. (
  • Here we glance at the mechanisms by which neutrophils recognize and face biofilms in implant infections and discuss the implications of this interplay, as well as speculate on its significance. (
  • Neutrophils (also known as neutrocytes or heterophils ) are the most abundant type of granulocytes and make up 40% to 70% of all white blood cells in humans. (
  • a ) Invasive micropapillary carcinoma composed of clusters of tumor cells within cleft-like spaces, characteristic inverse cell polarity and abundant intraepithelial and stromal tumor-infiltrating neutrophils (hematoxylin and eosin stain, magnification ×200). (
  • Myeloperoxidase, the most abundant neutrophil-granule protein, is known to have potent microbicidal properties. (
  • Neutrophil granulocytes , generally referred to as neutrophils , are the most abundant type of white blood cells in humans and form an integral part of the immune system . (
  • Neutrophils, along with eosinophils and basophils , constitute a group of white blood cells known as granulocytes . (
  • Absolute neutrophils are derived from what is called the differential: you take the total white blood cell count and differentiate the percentage of white blood cell species that make up the whole (neutrophils, eosinophils, basophils, lymphocytes and monocytes). (
  • 4 C/EBPε is expressed at the promyelocyte to myelocyte stage, and knockout mice lack neutrophils and eosinophils because of a block at this stage. (
  • A neutrophil is a granular, nucleated leukocyte , and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes. (
  • Supernatant from degranulated neutrophils killed the pneumococcus, suggesting a role for granular products. (
  • Suratt BT, Young SK, Lieber J, Nick JA, Henson PM, Worthen GS (2001) Neutrophil maturation and activation determine anatomic site of clearance from circulation. (
  • 5 Also, induction of C/EBPε by G-CSF is important for inducing neutrophil maturation. (
  • As this occurs, the granules of the neutrophil are depleted (degranulation). (
  • Part IV includes protocols that measure neutrophil apoptosis, calcium signal transduction, degranulation and detection of cytoplasmic granules, gene expression, transcription factors, and apoptosis. (
  • Human recombinant tumor necrosis factor (TNF) was shown to be a weak direct stimulus of the neutrophil respiratory burst and degranulation. (
  • An abnormally high number of neutrophils circulating in the blood is called neutrophilia. (
  • the term is usually used with reference to band ( q.v. ) or other "juvenile" neutrophils, which are neutrophilic granulocytes in which the nucleus is indented but not distinctly segmented. (
  • They found that mycobacterial mutants deficient in iron scavenging and lipid metabolism grew better in the setting of extensive neutrophilic infiltration than when there were few neutrophils. (
  • To make their discovery, the University of Maryland and Nanjing Medical University scientists used a form of microscopy, known as intravital microscopy, to visualize in mice the dynamic interactions of neutrophils with C. neoformans arrested in the brain microvasculature. (
  • Mice depleted of neutrophils had influenza-activated T cells. (
  • In contrast, failure of neutrophils to accumulate at these sites in 5C6-treated mice allowed Listeria to multiply extensively in hepatocytes without destroying them. (
  • Using conditional knockout mice lacking Opa1 in neutrophils ( Opa1 N∆ ), we report that lack of OPA1 reduces the activity of mitochondrial electron transport complex I in neutrophils. (
  • In mice, blocking a neutrophil receptor prevented the cells from entering the brain, and reduced amyloid load and microgliosis, as well as giving the animals a boost in long-term memory. (
  • In 5xFAD mice (middle), but not wild-type (left), neutrophils (red) squeeze out of blood vessels (green) and into the brain. (
  • She was intrigued by the fact that brain endothelial cells in both 5xFAD and 3xTg mice expressed high levels of adhesion factors, suggesting they might capture circulating white blood cells, particularly neutrophils. (
  • To test the role of this integrin, the authors isolated neutrophils from integrin knockout mice and injected them into 5xFAD animals. (
  • Here, Mishra and colleagues used a variety of chemical and genetic perturbations to reduce the number of lung neutrophils in these mice. (
  • Mishra and colleagues extended their findings to human disease by establishing which mediators act downstream of IL-1 to recruit neutrophils in mice, identifying ALOX15, a 12/15-lipoxygenase that produces 12-hydroxyeicosatetraenoic acid (12-HETE). (
  • These studies suggest that in M. tuberculosis -infected humans, as in mice, 12-lipoxygenase metabolites recruit neutrophils that harbor the enemy and drive disease pathogenesis. (
  • D, percentage of living neutrophils in the tumors of control mice and S. typhimurium -infected mice at different times p.i. (
  • The percentage of such cells in the blood of neutrophil-depleted mice was normalized to the percentage of nondepleted tumor-bearing control mice. (
  • D, percentage of living neutrophils in the tumors of control mice and anti-Gr1-treated mice at different times after treatment. (
  • At subsaturating concentrations of fMLP, LTB 4 secretion enhanced actin polymerization at the leading edge of neutrophils and stabilized polarization. (
  • Neutrophils are Leukocytes (white blood cells) of the Polymorphonuclear Leukocyte subgroup. (
  • My CBC came back with high WBC of 14.1, high neutrophils of 9.6 and high leukocytes of 3.57. (
  • Hello,A moderate in increase of leukocytes with absolute increase in neutrophils is generally seen in bacterial infections, corticosteroid administration,abscess formation,ketoacidosis,neoplasia etc. (
  • Leukocytes prepared from venous blood samples drawn from two volunteers were incubated alone or with opsonized zymogen for 1 hour at 37 degrees-C to stimulate the neutrophils. (
  • Neutrophils constitute 60% of the circulating leukocytes. (
  • Eat fruits and vegetables high in vitamin C. This vitamin is a great way to boost your immune system and ensure your neutrophil levels do not fall too low. (
  • Neutrophils are a key cell type of nonadaptive immune system and are the first phagocytic cell type that reaches mucosal inflammatory sites. (
  • Neutrophils can do this by exchanging information with macrophages, dendritic cells, and other cells of the adaptive immune system through either soluble mediators or direct cell-cell contact. (
  • This study suggests that T cells also don't really know where to go without the help of key innate immune system cells like neutrophils. (
  • Polymorphonuclear neutrophils, or granulocytes, are essential effector cells of the innate immune system against bacterial infections. (
  • It will be interesting to determine whether specific neutrophil subsets are to blame and, if so, their role in other pulmonary infections. (
  • An emerging concept is that different neutrophil subsets exist, which might exhibit separate functional properties. (
  • In support of the existence of distinct neutrophil subsets in the ischemic heart, transcriptional changes in cardiac neutrophils have been reported within the first few days after myocardial infarction. (
  • A, at 2 d p.i., blood samples were taken and analyzed by flow cytometry for the presence of neutrophils. (
  • The peripheral blood smears made from EDTA-anticoagulated blood showed golden-brown refractile crystals in the cytoplasm of neutrophils. (
  • The objective of this paper is to review in what forms sex chromatin can appear in peripheral blood neutrophils and how sex determination can be done using sex chromatin appendages. (
  • Miknienė, Z. and Ivanauskaitė, R. (2018) Sex Chromatin in Peripheral Blood Neutrophils and Sex Determination. (
  • Now, researchers led by Gabriela Constantin at the University of Verona, Italy, turn the spotlight on an overlooked peripheral cell: the neutrophil. (
  • This reduction was not due to peripheral neutrophil cell death, impaired differentiation, or the presence of anti-neutrophil antibodies. (
  • Part II describes commonly used methods to isolate neutrophils from humans and other animal species. (
  • Neutrophils are the most common type of white blood cell in humans. (
  • Whereas basophilic white blood cells stain dark blue and eosinophilic white blood cells stain bright red, neutrophils stain a neutral pink. (
  • This is noted in a manual review of the blood smear and is positive when most or all of the neutrophils have 5 or more segments. (
  • Vitamin E is essential for stimulating the production of white blood cells, and zinc is important for increasing neutrophils. (
  • On the last stage of their journey from the blood stream to a mucosal surface, neutrophils cross a generally sealed epithelium by migrating along the paracellular pathway to the luminal side of the epithelial layer. (
  • Neutrophils are a type of white blood cell. (
  • In fact, most of the white blood cells that lead the immune system's response are neutrophils. (
  • Neutrophils are the most plentiful type, making up 55 to 70 percent of your white blood cells. (
  • Neutrophils are important because, unlike some of the other white blood cells, they aren't limited to a specific area of circulation. (
  • absolute neutrophil count (ANC), the number of neutrophils in a milliliter of blood, having a reference value of approximately 1500-7700 per μL. (
  • It is calculated by adding the number of segmented neutrophils and the number of basal neutrophils and multiplying the sum by the total white blood cell (WBC) count. (
  • Neutrophils are the actual number of neutrophils in a milliliter of blood. (
  • So if your total white blood cell count total is number X, and the differential shows neutrophils make up say, 1/3 of the total count, then the absolute neutrophils equal X times 1/3. (
  • Neutrophils are just one of the many kinds of white blood cells. (
  • The range (in percents) for neutrophils is 40-70% of the total white blood cells - so your neutrophil percentage is in the low range of normal. (
  • Since you neutrophil count is reported as percentage, then that is the differential - 46% of your white blood cells are neutrophils as opposed to the other species. (
  • my husband had blood work done, came back with absolute neutrophil count of 8147, wbc of 11.1, he is a long time drinker but other 'liver function tests' have been normal. (
  • For the purposes of these studies, we anticipate that 20-25 mls of blood will be sufficient from both patients and healthy volunteer controls to have adequate numbers of neutrophils for study. (
  • We will perform ex vivo killing assays using neutrophils purified from whole blood in CF patients and normal controls. (
  • The neutrophil blood test is a primary investigation for diagnosing certain conditions as well as monitoring them. (
  • The neutrophil blood test forms part of the differential white blood cell count which also measures other white blood cells like lymphocytes, monocytes and basophils. (
  • This gives the proportion of neutrophils in the blood. (
  • Neutrophils in the blood can be expressed either as absolute neutrophil count or as a percentage of the total white blood cell count. (
  • Neutrophils can also be expressed as a percentage of the total whole blood cell count. (
  • Neutrophils constitute 40-60% of the total white blood cells. (
  • An abnormal neutrophil blood test means either an increase or decrease in the proportion of neutrophils in the blood. (
  • Laboratory tests showed a total bilirubin level of 764.7 µmol/L (44.7 mg/dL) and direct bilirubin of 37 µmol/L. Hemoglobin was 178 g/L, white cell count 26.1 × 10 9 /L, neutrophils 16.1 × 10 9 /L, lymphocytes 5.8 × 10 9 /L, and monocytes 3.0 × 10 9 /L. There was no blood group incompatibility with mother. (
  • According to National Institutes of Health, normal neutrophil levels should be between 2500 and 6000 neutrophils per mm3 (cubic millimetre) of blood. (
  • Despite the daily clinical use of neutrophil band forms count in the care of septic patients and their abundance in septic blood, no information exists on the fate of these cells, nor on their capacity to mount an efficient innate immune response. (
  • Sex chromatin is an approximately 1 micron clump of chromatin seen usually at the periphery of female nuclei in certain tissues and called "Barr body" and as a drumstick in polymor phonuclear neutrophils nuclei in the blood smears. (
  • In the study, researchers found that neutrophils, a type of white blood cell, of asthmatics move more slowly than the cells of those without asthma. (
  • Previously it was impractical to use neutrophils, as it required a fair amount of blood, according to a statement from the University of Wisconsin, from which some of the researchers hail. (
  • The device can sort neutrophils from a drop of whole blood within minutes, and was used in a clinical setting to characterize asthmatic and non-asthmatic patients," the researchers wrote in the study, published in Proceedings of the National Academy of Sciences. (
  • In the blood compartment, neutrophils can be characterized as belonging to one of three groups: resting, primed, and systemically activated. (
  • As a result primed and systemically activated blood neutrophils can be sequestered in the lung when lung vascular endothelium becomes activated by systemic inflammatory mediators. (
  • Many neutrophils (right) also tarry on blood vessel walls near Aβ deposits (blue). (
  • In live imaging experiments, they saw neutrophils crawling along brain blood vessels near amyloid deposits (see image above). (
  • These pancreas-infiltrating neutrophils mainly localized at the level of very small blood vessels. (
  • Hi, I was wondering does anyone know if it possible to isolate neutrophils and PBMCs simultaneously from whole blood? (
  • C, length of neutrophil depletion in the blood after triple injection of anti-Gr1 at consecutive days. (
  • Biology textbooks are blunt - neutrophils are mindless killers. (
  • This volume provides a concise set of protocols for assessing basic neutrophil functions and investigating specialized areas in neutrophil biology. (
  • Part I contains overviews of neutrophil biology, function, and disorders. (
  • Neutrophil Methods and Protocols: Third Edition is a comprehensive source for detailed explanations and applications of the most modern methodological advances in neutrophil biology. (
  • Lymphocytes and neutrophils are often seen alongside one another, each helping in its own way. (
  • Leading investigators uncover novel aspects of neutrophils, such as their capacity to control gene expression at the transcriptional level, or respond to proinflammatory cytokines, cytokine receptor chains (gc) and endogenous anti-inflammatory lipid mediators. (
  • The granules of neutrophils typically stain pink or purple-blue following treatment with a dye. (
  • The granules of the neutrophil are microscopic packets of potent enzymes capable of digesting many types of cellular materials. (
  • Neutrophils contain several subcellular granule compartments, including primary (azurophilic), secondary (specific), tertiary (gelatinase) granules, and a fourth compartment called secretory vesicles. (
  • In resting neutrophils, SIRPα was found to be present in the plasma membrane and in all types of granules except for the azurophilic granules. (
  • The average mature neutrophil has a diameter of about 13-15µm and a granulated cytoplasm. (
  • During the apoptosis process, neutrophils exhibit marked morphological changes, such as cytoplasm condensation, organelle aggregations, nuclear chromatin cleavage, formation of apoptotic bodies, and reduction in cell volume ( 13 , 14 ). (
  • NETs were made by activated neutrophils. (
  • B ) Upon stimulation with 25 nM PMA for 30 min, the cells flatten, make many membrane protrusions, and form fibers (NETs), arrows in (B) and (D). ( C ) TEM analysis of naïve neutrophils in suspension. (
  • When neutrophils get overwhelmed, when they can no longer deal with a microbial threat by just engulfing it, that's when the NETs are released. (
  • Tumor-associated macrophages (TAMs) and tumor-associated neutrophils (TANs) can control cancer growth and exist in almost all solid neoplasms. (
  • Also, neutrophils in tumor-bearing subjects can act to eliminate disseminated tumor cells, and thus provide antimetastatic protection ( 9 ). (
  • Tumor-infiltrating neutrophils in pancreatic neoplasia. (
  • In this study, the presence of tumor-infiltrating neutrophils within and/or adjacent to neoplastic cells was investigated in pancreatic neoplasms. (
  • 10 tumor-infiltrating neutrophils/100 epithelial cells were arbitrarily classified as positive. (
  • Among 363 invasive ductal carcinomas, 15 showed significant tumor-infiltrating neutrophils (8 were micropapillary carcinomas and 7 were undifferentiated carcinomas). (
  • range, 14-63 tumor-infiltrating neutrophils). (
  • Among intraductal papillary mucinous neoplasms, significant tumor-infiltrating neutrophils were identified in 4/16 pancreatobiliary type, but were uncommon in other types (1/11 oncocytic and 1/23 intestinal types had borderline tumor-infiltrating neutrophils, and 0/10 gastric type had tumor-infiltrating neutrophils). (
  • Non-carcinomatous (low-grade and non-papillary) components of these neoplasms did not have tumor-infiltrating neutrophils. (
  • Tumor-infiltrating neutrophils were not striking in neuroendocrine tumors (40), serous cystadenomas (18), acinar cell carcinomas (9) or solid-pseudopapillary neoplasms (8). (
  • In conclusion, significant tumor-infiltrating neutrophils are uncommon in pancreatic ductal adenocarcinoma, and when they occur it is typically in the micropapillary and undifferentiated types with a known poor prognosis. (
  • Larger studies are needed to investigate the association between tumor-infiltrating neutrophils and pancreatic neoplasms and their role in their clinical behavior. (
  • Note significant numbers of tumor-infiltrating neutrophils within the stroma (hematoxylin and eosin stain, magnification ×200). (
  • Stimulation of neutrophils by tumor necrosis factor. (
  • Effects of neutrophil-derived products on the tumor microenvironment. (
  • Neutrophil-derived products play critical roles in a wide range of stages of tumor progression from the initial genotoxic insult to metastasis to distant sites. (
  • Although MMP-8 has a proven role in increasing the tumor cell's ability to bind laminin and collagen, thus reducing the ability of these cells to metastasize (green arrow), the majority of the neutrophil's effects are protumor (red arrows), consistent with the poor prognosis associated with neutrophils at the tumor site. (
  • Specific programmed cell death (apoptotic) pathways regulate neutrophil homeostasis, where an inflammatory milieu can prolong the life span of neutrophils to several days, whereas non-activated neutrophils are committed to constitutive/spontaneous apoptosis within hours. (
  • During neutrophil apoptosis, several receptors are known to be shed from the cell surface (e.g. (
  • During apoptosis, SIRPα is shed from the cell surface, which may be one mechanism contributing to the well-known down-regulation in the adhesiveness of apoptotic neutrophils. (
  • TNF does not act as an opsonin but, rather, reacts with the neutrophil to increase its phagocytic activity. (
  • The mature form of polymorphonuclear neutrophil (PMN) has a nucleus with three to five lobes connected by slender threads of chromatin . (
  • Neutrophils with segmented nuclei surrounded by erythrocytes and platelets . (
  • Neutrophils are a type of phagocyte and are normally found in the bloodstream . (
  • When circulating in the bloodstream and inactivated, neutrophils are spherical. (
  • In your bloodstream, there are neutrophils that, when faced with a pathogenic threat, will expel their DNA like a net to contain it. (
  • The current paradigm for neutrophil responses to multiple chemoattractants has evolved from observations of their response to opposing gradients and indicate that neutrophils prioritize between different groups of chemoattractants. (