Complement c3a. Medical search

A glycoprotein that is central in both the classical and the alternative pathway of COMPLEMENT ACTIVATION. C3 can be cleaved into COMPLEMENT C3A and COMPLEMENT C3B, spontaneously at low level or by C3 CONVERTASE at high level. The smaller fragment C3a is an ANAPHYLATOXIN and mediator of local inflammatory process. The larger fragment C3b binds with C3 convertase to form C5 convertase.

A glycoprotein that is important in the activation of CLASSICAL COMPLEMENT PATHWAY. C4 is cleaved by the activated COMPLEMENT C1S into COMPLEMENT C4A and COMPLEMENT C4B.

The smaller fragment formed when complement C4 is cleaved by COMPLEMENT C1S. It is an anaphylatoxin that causes symptoms of immediate hypersensitivity (HYPERSENSITIVITY, IMMEDIATE) but its activity is weaker than that of COMPLEMENT C3A or COMPLEMENT C5A.

The smaller fragment generated from the cleavage of complement C3 by C3 CONVERTASE. C3a, a 77-amino acid peptide, is a mediator of local inflammatory process. It induces smooth MUSCLE CONTRACTION, and HISTAMINE RELEASE from MAST CELLS and LEUKOCYTES. C3a is considered an anaphylatoxin along with COMPLEMENT C4A; COMPLEMENT C5A; and COMPLEMENT C5A, DES-ARGININE.

A subcomponent of complement C1, composed of six copies of three polypeptide chains (A, B, and C), each encoded by a separate gene (C1QA; C1QB; C1QC). This complex is arranged in nine subunits (six disulfide-linked dimers of A and B, and three disulfide-linked homodimers of C). C1q has binding sites for antibodies (the heavy chain of IMMUNOGLOBULIN G or IMMUNOGLOBULIN M). The interaction of C1q and immunoglobulin activates the two proenzymes COMPLEMENT C1R and COMPLEMENT C1S, thus initiating the cascade of COMPLEMENT ACTIVATION via the CLASSICAL COMPLEMENT PATHWAY.

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.

The sequential activation of serum COMPLEMENT PROTEINS to create the COMPLEMENT MEMBRANE ATTACK COMPLEX. Factors initiating complement activation include ANTIGEN-ANTIBODY COMPLEXES, microbial ANTIGENS, or cell surface POLYSACCHARIDES.

The large fragment formed when COMPLEMENT C4 is cleaved by COMPLEMENT C1S. The membrane-bound C4b binds COMPLEMENT C2A, a SERINE PROTEASE, to form C4b2a (CLASSICAL PATHWAY C3 CONVERTASE) and subsequent C4b2a3b (CLASSICAL PATHWAY C5 CONVERTASE).

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.

The larger fragment generated from the cleavage of COMPLEMENT C3 by C3 CONVERTASE. It is a constituent of the ALTERNATIVE PATHWAY C3 CONVERTASE (C3bBb), and COMPLEMENT C5 CONVERTASES in both the classical (C4b2a3b) and the alternative (C3bBb3b) pathway. C3b participates in IMMUNE ADHERENCE REACTION and enhances PHAGOCYTOSIS. It can be inactivated (iC3b) or cleaved by various proteases to yield fragments such as COMPLEMENT C3C; COMPLEMENT C3D; C3e; C3f; and C3g.

Serum glycoproteins participating in the host defense mechanism of COMPLEMENT ACTIVATION that creates the COMPLEMENT MEMBRANE ATTACK COMPLEX. Included are glycoproteins in the various pathways of complement activation (CLASSICAL COMPLEMENT PATHWAY; ALTERNATIVE COMPLEMENT PATHWAY; and LECTIN COMPLEMENT PATHWAY).

A 105-kDa serum glycoprotein with significant homology to the other late complement components, C7-C9. It is a polypeptide chain cross-linked by 32 disulfide bonds. C6 is the next complement component to bind to the membrane-bound COMPLEMENT C5B in the assembly of MEMBRANE ATTACK COMPLEX. It is encoded by gene C6.

A 206-amino-acid fragment in the alpha chain (672-1663) of C3b. It is generated when C3b is inactivated (iC3b) and its alpha chain is cleaved by COMPLEMENT FACTOR I into C3c (749-954), and C3dg (955-1303) in the presence COMPLEMENT FACTOR H.

A 302-amino-acid fragment in the alpha chain (672-1663) of C3b. It is generated when C3b is inactivated (iC3b) and its alpha chain is cleaved by COMPLEMENT FACTOR I into C3c, and C3dg (955-1303) in the presence COMPLEMENT FACTOR H. Serum proteases further degrade C3dg into C3d (1002-1303) and C3g (955-1001).

A component of the CLASSICAL COMPLEMENT PATHWAY. C2 is cleaved by activated COMPLEMENT C1S into COMPLEMENT C2B and COMPLEMENT C2A. C2a, the COOH-terminal fragment containing a SERINE PROTEASE, combines with COMPLEMENT C4B to form C4b2a (CLASSICAL PATHWAY C3 CONVERTASE) and subsequent C4b2a3b (CLASSICAL PATHWAY C5 CONVERTASE).

A 63-kDa serum glycoprotein encoded by gene C9. Monomeric C9 (mC9) binds the C5b-8 complex to form C5b-9 which catalyzes the polymerization of C9 forming C5b-p9 (MEMBRANE ATTACK COMPLEX) and transmembrane channels leading to lysis of the target cell. Patients with C9 deficiency suffer from recurrent bacterial infections.

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 77-kDa subcomponent of complement C1, encoded by gene C1S, is a SERINE PROTEASE existing as a proenzyme (homodimer) in the intact complement C1 complex. Upon the binding of COMPLEMENT C1Q to antibodies, the activated COMPLEMENT C1R cleaves C1s into two chains, A (heavy) and B (light, the serine protease), linked by disulfide bonds yielding the active C1s. The activated C1s, in turn, cleaves COMPLEMENT C2 and COMPLEMENT C4 to form C4b2a (CLASSICAL C3 CONVERTASE).

A product of COMPLEMENT ACTIVATION cascade, regardless of the pathways, that forms transmembrane channels causing disruption of the target CELL MEMBRANE and cell lysis. It is formed by the sequential assembly of terminal complement components (COMPLEMENT C5B; COMPLEMENT C6; COMPLEMENT C7; COMPLEMENT C8; and COMPLEMENT C9) into the target membrane. The resultant C5b-8-poly-C9 is the "membrane attack complex" or MAC.

A 80-kDa subcomponent of complement C1, existing as a SERINE PROTEASE proenzyme in the intact complement C1 complex. When COMPLEMENT C1Q is bound to antibodies, the changed tertiary structure causes autolytic activation of complement C1r which is cleaved into two chains, A (heavy) and B (light, the serine protease), connected by disulfide bonds. The activated C1r serine protease, in turn, activates COMPLEMENT C1S proenzyme by cleaving the Arg426-Ile427 bond. No fragment is released when either C1r or C1s is cleaved.

Serum proteins that negatively regulate the cascade process of COMPLEMENT ACTIVATION. Uncontrolled complement activation and resulting cell lysis is potentially dangerous for the host. The complement system is tightly regulated by inactivators that accelerate the decay of intermediates and certain cell surface receptors.

A 93-kDa serum glycoprotein encoded by C7 gene. It is a polypeptide chain with 28 disulfide bridges. In the formation of MEMBRANE ATTACK COMPLEX; C7 is the next component to bind the C5b-6 complex forming a trimolecular complex C5b-7 which is lipophilic, resembles an integral membrane protein, and serves as an anchor for the late complement components, C8 and C9.

Serine proteases that cleave COMPLEMENT C3 into COMPLEMENT C3A and COMPLEMENT C3B, or cleave COMPLEMENT C5 into COMPLEMENT C5A and COMPLEMENT C5B. These include the different forms of C3/C5 convertases in the classical and the alternative pathways of COMPLEMENT ACTIVATION. Both cleavages take place at the C-terminal of an ARGININE residue.

A glycine-rich, heat-labile serum glycoprotein that contains a component of the C3 CONVERTASE ALTERNATE PATHWAY (C3bBb). Bb, a serine protease, is generated when factor B is cleaved by COMPLEMENT FACTOR D into Ba and Bb.

Complement activation initiated by the interaction of microbial ANTIGENS with COMPLEMENT C3B. When COMPLEMENT FACTOR B binds to the membrane-bound C3b, COMPLEMENT FACTOR D cleaves it to form alternative C3 CONVERTASE (C3BBB) which, stabilized by COMPLEMENT FACTOR P, is able to cleave multiple COMPLEMENT C3 to form alternative C5 CONVERTASE (C3BBB3B) leading to cleavage of COMPLEMENT C5 and the assembly of COMPLEMENT MEMBRANE ATTACK COMPLEX.

Complement activation initiated by the binding of COMPLEMENT C1 to ANTIGEN-ANTIBODY COMPLEXES at the COMPLEMENT C1Q subunit. This leads to the sequential activation of COMPLEMENT C1R and COMPLEMENT C1S subunits. Activated C1s cleaves COMPLEMENT C4 and COMPLEMENT C2 forming the membrane-bound classical C3 CONVERTASE (C4B2A) and the subsequent C5 CONVERTASE (C4B2A3B) leading to cleavage of COMPLEMENT C5 and the assembly of COMPLEMENT MEMBRANE ATTACK COMPLEX.

A 150-kDa serum glycoprotein composed of three subunits with each encoded by a different gene (C8A; C8B; and C8G). This heterotrimer contains a disulfide-linked C8alpha-C8gamma heterodimer and a noncovalently associated C8beta chain. C8 is the next component to bind the C5-7 complex forming C5b-8 that binds COMPLEMENT C9 and acts as a catalyst in the polymerization of C9.

The first complement component to act in the activation of CLASSICAL COMPLEMENT PATHWAY. It is a calcium-dependent trimolecular complex made up of three subcomponents: COMPLEMENT C1Q; COMPLEMENT C1R; and COMPLEMENT C1S at 1:2:2 ratios. When the intact C1 binds to at least two antibodies (involving C1q), C1r and C1s are sequentially activated, leading to subsequent steps in the cascade of COMPLEMENT ACTIVATION.

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.

An important soluble regulator of the alternative pathway of complement activation (COMPLEMENT ACTIVATION PATHWAY, ALTERNATIVE). It is a 139-kDa glycoprotein expressed by the liver and secreted into the blood. It binds to COMPLEMENT C3B and makes iC3b (inactivated complement 3b) susceptible to cleavage by COMPLEMENT FACTOR I. Complement factor H also inhibits the association of C3b with COMPLEMENT FACTOR B to form the C3bB proenzyme, and promotes the dissociation of Bb from the C3bBb complex (COMPLEMENT C3 CONVERTASE, ALTERNATIVE PATHWAY).

The larger fragment generated from the cleavage of C5 by C5 CONVERTASE that yields COMPLEMENT C5A and C5b (beta chain + alpha' chain, the residual alpha chain, bound by disulfide bond). C5b remains bound to the membrane and initiates the spontaneous assembly of the late complement components to form C5b-8-poly-C9, the MEMBRANE ATTACK COMPLEX.

The COOH-terminal fragment of COMPLEMENT 2, released by the action of activated COMPLEMENT C1S. It is a SERINE PROTEASE. C2a combines with COMPLEMENT C4B to form C4b2a (CLASSICAL PATHWAY C3 CONVERTASE) and subsequent C4b2a3b (CLASSICAL PATHWAY C5 CONVERTASE).

A G-protein-coupled receptor that signals an increase in intracellular calcium in response to the potent ANAPHYLATOXIN peptide COMPLEMENT C5A.

Enzymes that activate one or more COMPLEMENT PROTEINS in the complement system leading to the formation of the COMPLEMENT MEMBRANE ATTACK COMPLEX, an important response in host defense. They are enzymes in the various COMPLEMENT ACTIVATION pathways.

Compounds that negatively regulate the cascade process of COMPLEMENT ACTIVATION. Uncontrolled complement activation and resulting cell lysis is potentially dangerous for the host.

A screening assay for circulating COMPLEMENT PROTEINS. Diluted SERUM samples are added to antibody-coated ERYTHROCYTES and the percentage of cell lysis is measured. The values are expressed by the so called CH50, in HEMOLYTIC COMPLEMENT units per milliliter, which is the dilution of serum required to lyse 50 percent of the erythrocytes in the assay.

Serum proteins that inhibit, antagonize, or inactivate COMPLEMENT C1 or its subunits.

Molecular sites on or in B-lymphocytes, follicular dendritic cells, lymphoid cells, and epithelial cells that recognize and combine with COMPLEMENT C3D. Human complement receptor 2 (CR2) serves as a receptor for both C3dg and the gp350/220 glycoprotein of HERPESVIRUS 4, HUMAN, and binds the monoclonal antibody OKB7, which blocks binding of both ligands to the receptor.

Serum peptides derived from certain cleaved COMPLEMENT PROTEINS during COMPLEMENT ACTIVATION. They induce smooth MUSCLE CONTRACTION; mast cell HISTAMINE RELEASE; PLATELET AGGREGATION; and act as mediators of the local inflammatory process. The order of anaphylatoxin activity from the strongest to the weakest is C5a, C3a, C4a, and C5a des-arginine.

Serologic tests based on inactivation of complement by the antigen-antibody complex (stage 1). Binding of free complement can be visualized by addition of a second antigen-antibody system such as red cells and appropriate red cell antibody (hemolysin) requiring complement for its completion (stage 2). Failure of the red cells to lyse indicates that a specific antigen-antibody reaction has taken place in stage 1. If red cells lyse, free complement is present indicating no antigen-antibody reaction occurred in stage 1.

A serum protein which is important in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY. This enzyme cleaves the COMPLEMENT C3B-bound COMPLEMENT FACTOR B to form C3bBb which is ALTERNATIVE PATHWAY C3 CONVERTASE.

A plasma serine proteinase that cleaves the alpha-chains of C3b and C4b in the presence of the cofactors COMPLEMENT FACTOR H and C4-binding protein, respectively. It is a 66-kDa glycoprotein that converts C3b to inactivated C3b (iC3b) followed by the release of two fragments, C3c (150-kDa) and C3dg (41-kDa). It was formerly called KAF, C3bINF, or enzyme 3b inactivator.

A serum protein that regulates the CLASSICAL COMPLEMENT ACTIVATION PATHWAY. It binds as a cofactor to COMPLEMENT FACTOR I which then hydrolyzes the COMPLEMENT C4B in the CLASSICAL PATHWAY C3 CONVERTASE (C4bC2a).

Endogenous proteins that inhibit or inactivate COMPLEMENT C3B. They include COMPLEMENT FACTOR H and COMPLEMENT FACTOR I (C3b/C4b inactivator). They cleave or promote the cleavage of C3b into inactive fragments, and thus are important in the down-regulation of COMPLEMENT ACTIVATION and its cytolytic sequence.

GPI-linked membrane proteins broadly distributed among hematopoietic and non-hematopoietic cells. CD55 prevents the assembly of C3 CONVERTASE or accelerates the disassembly of preformed convertase, thus blocking the formation of the membrane attack complex.

Important enzymes in the CLASSICAL COMPLEMENT ACTIVATION PATHWAY. They cleave COMPLEMENT C3 and COMPLEMENT C5.

The N-terminal fragment of COMPLEMENT 2, released by the action of activated COMPLEMENT C1S.

Small glycoproteins found on both hematopoietic and non-hematopoietic cells. CD59 restricts the cytolytic activity of homologous complement by binding to C8 and C9 and blocking the assembly of the membrane attack complex. (From Barclay et al., The Leukocyte Antigen FactsBook, 1993, p234)

Venoms from snakes of the genus Naja (family Elapidae). They contain many specific proteins that have cytotoxic, hemolytic, neurotoxic, and other properties. Like other elapid venoms, they are rich in enzymes. They include cobramines and cobralysins.

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.

An adrenal microsomal cytochrome P450 enzyme that catalyzes the 21-hydroxylation of steroids in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP21 gene, converts progesterones to precursors of adrenal steroid hormones (CORTICOSTERONE; HYDROCORTISONE). Defects in CYP21 cause congenital adrenal hyperplasia (ADRENAL HYPERPLASIA, CONGENITAL).

Important enzymes in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY. They cleave COMPLEMENT C3 and COMPLEMENT C5.

An endogenous 105-kDa plasma glycoprotein produced primarily by the LIVER and MONOCYTES. It inhibits a broad spectrum of proteases, including the COMPLEMENT C1R and the COMPLEMENT C1S proteases of the CLASSICAL COMPLEMENT PATHWAY, and the MANNOSE-BINDING PROTEIN-ASSOCIATED SERINE PROTEASES. C1-INH-deficient individuals suffer from HEREDITARY ANGIOEDEMA TYPES I AND II.

The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.

The destruction of ERYTHROCYTES by many different causal agents such as antibodies, bacteria, chemicals, temperature, and changes in tonicity.

A serine protease that is the complex of COMPLEMENT C3B and COMPLEMENT FACTOR BB. It cleaves multiple COMPLEMENT C3 into COMPLEMENT C3A (anaphylatoxin) and COMPLEMENT C3B in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY.

A serine protease that cleaves multiple COMPLEMENT 5 into COMPLEMENT 5A (anaphylatoxin) and COMPLEMENT 5B in the CLASSICAL COMPLEMENT ACTIVATION PATHWAY. It is a complex of CLASSICAL PATHWAY C3 CONVERTASE (C4b2a) with an additional COMPLEMENT C3B, or C4b2a3b.

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.

A serine protease that cleaves multiple COMPLEMENT 3 into COMPLEMENT 3A (anaphylatoxin) and COMPLEMENT 3B in the CLASSICAL COMPLEMENT ACTIVATION PATHWAY. It is a complex of COMPLEMENT 4B and COMPLEMENT 2A (C4b2a).

A ubiquitously expressed complement receptor that binds COMPLEMENT C3B and COMPLEMENT C4B and serves as a cofactor for their inactivation. CD46 also interacts with a wide variety of pathogens and mediates immune response.

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.

Proteins that are present in blood serum, including SERUM ALBUMIN; BLOOD COAGULATION FACTORS; and many other types of proteins.

A chronic, relapsing, inflammatory, and often febrile multisystemic disorder of connective tissue, characterized principally by involvement of the skin, joints, kidneys, and serosal membranes. It is of unknown etiology, but is thought to represent a failure of the regulatory mechanisms of the autoimmune system. The disease is marked by a wide range of system dysfunctions, an elevated erythrocyte sedimentation rate, and the formation of LE cells in the blood or bone marrow.

A serine protease that cleaves multiple COMPLEMENT C5 into COMPLEMENT C5A (anaphylatoxin) and COMPLEMENT C5B in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY. It is the complex of ALTERNATIVE PATHWAY C3 CONVERTASE (C3bBb) with an additional COMPLEMENT C3B, or C3bBb3b.

The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (PHAGOCYTES).

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.

Complement activation triggered by the interaction of microbial POLYSACCHARIDES with serum MANNOSE-BINDING LECTIN resulting in the activation of MANNOSE-BINDING PROTEIN-ASSOCIATED SERINE PROTEASES. As in the classical pathway, MASPs cleave COMPLEMENT C4 and COMPLEMENT C2 to form C3 CONVERTASE (C4B2A) and the subsequent C5 CONVERTASE (C4B2A3B) leading to cleavage of COMPLEMENT C5 and assembly of COMPLEMENT MEMBRANE ATTACK COMPLEX.

A 53-kDa protein that is a positive regulator of the alternate pathway of complement activation (COMPLEMENT ACTIVATION PATHWAY, ALTERNATIVE). It stabilizes the ALTERNATIVE PATHWAY C3 CONVERTASE (C3bBb) and protects it from rapid inactivation, thus facilitating the cascade of COMPLEMENT ACTIVATION and the formation of MEMBRANE ATTACK COMPLEX. Individuals with mutation in the PFC gene exhibit properdin deficiency and have a high susceptibility to infections.

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).

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.

The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.

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 sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.

A cluster of convoluted capillaries beginning at each nephric tubule in the kidney and held together by connective tissue.

The clear portion of BLOOD that is left after BLOOD COAGULATION to remove BLOOD CELLS and clotting proteins.

Chronic glomerulonephritis characterized histologically by proliferation of MESANGIAL CELLS, increase in the MESANGIAL EXTRACELLULAR MATRIX, and a thickening of the glomerular capillary walls. This may appear as a primary disorder or secondary to other diseases including infections and autoimmune disease SYSTEMIC LUPUS ERYTHEMATOSUS. Various subtypes are classified by their abnormal ultrastructures and immune deposits. Hypocomplementemia is a characteristic feature of all types of MPGN.

A class of immunoglobulin bearing mu chains (IMMUNOGLOBULIN MU-CHAINS). IgM can fix COMPLEMENT. The name comes from its high molecular weight and originally being called a macroglobulin.

A genus of trematode flukes belonging to the family Schistosomatidae. There are over a dozen species. These parasites are found in man and other mammals. Snails are the intermediate hosts.

A test used to determine whether or not complementation (compensation in the form of dominance) will occur in a cell with a given mutant phenotype when another mutant genome, encoding the same mutant phenotype, is introduced into that cell.

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.

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.

Inflammation of the renal glomeruli (KIDNEY GLOMERULUS) that can be classified by the type of glomerular injuries including antibody deposition, complement activation, cellular proliferation, and glomerulosclerosis. These structural and functional abnormalities usually lead to HEMATURIA; PROTEINURIA; HYPERTENSION; and RENAL INSUFFICIENCY.

Thickening of the walls of small ARTERIES or ARTERIOLES due to cell proliferation or HYALINE deposition.

Antibodies produced by a single clone of cells.

The genetic region which contains the loci of genes which determine the structure of the serologically defined (SD) and lymphocyte-defined (LD) TRANSPLANTATION ANTIGENS, genes which control the structure of the IMMUNE RESPONSE-ASSOCIATED ANTIGENS, HUMAN; the IMMUNE RESPONSE GENES which control the ability of an animal to respond immunologically to antigenic stimuli, and genes which determine the structure and/or level of the first four components of complement.

Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.

Antibodies that react with self-antigens (AUTOANTIGENS) of the organism that produced them.

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.

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.

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.)

Established cell cultures that have the potential to propagate indefinitely.

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.

Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.

Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.

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.

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 insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.

The parts of a macromolecule that directly participate in its specific combination with another molecule.

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.

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.

Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.

A specific mannose-binding member of the collectin family of lectins. It binds to carbohydrate groups on invading pathogens and plays a key role in the MANNOSE-BINDING LECTIN COMPLEMENT PATHWAY.

Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.

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).

Proteins prepared by recombinant DNA technology.

An IgG autoantibody against the ALTERNATIVE PATHWAY C3 CONVERTASE, found in serum of patients with MESANGIOCAPILLARY GLOMERULONEPHRITIS. The binding of this autoantibody to C3bBb stabilizes the enzyme thus reduces the actions of C3b inactivators (COMPLEMENT FACTOR H; COMPLEMENT FACTOR I). This abnormally stabilized enzyme induces a continuous COMPLEMENT ACTIVATION and generation of C3b thereby promoting the assembly of MEMBRANE ATTACK COMPLEX and cytolysis.

Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.

Multi-subunit proteins which function in IMMUNITY. They are produced by B LYMPHOCYTES from the IMMUNOGLOBULIN GENES. They are comprised of two heavy (IMMUNOGLOBULIN HEAVY CHAINS) and two light chains (IMMUNOGLOBULIN LIGHT CHAINS) with additional ancillary polypeptide chains depending on their isoforms. The variety of isoforms include monomeric or polymeric forms, and transmembrane forms (B-CELL ANTIGEN RECEPTORS) or secreted forms (ANTIBODIES). They are divided by the amino acid sequence of their heavy chains into five classes (IMMUNOGLOBULIN A; IMMUNOGLOBULIN D; IMMUNOGLOBULIN E; IMMUNOGLOBULIN G; IMMUNOGLOBULIN M) and various subclasses.

Plasma glycoproteins that form a stable complex with hemoglobin to aid the recycling of heme iron. They are encoded in man by a gene on the short arm of chromosome 16.

A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).

A biosensing technique in which biomolecules capable of binding to specific analytes or ligands are first immobilized on one side of a metallic film. Light is then focused on the opposite side of the film to excite the surface plasmons, that is, the oscillations of free electrons propagating along the film's surface. The refractive index of light reflecting off this surface is measured. When the immobilized biomolecules are bound by their ligands, an alteration in surface plasmons on the opposite side of the film is created which is directly proportional to the change in bound, or adsorbed, mass. Binding is measured by changes in the refractive index. The technique is used to study biomolecular interactions, such as antigen-antibody binding.

Peptides whose amino and carboxy ends are linked together with a peptide bond forming a circular chain. Some of them are ANTI-INFECTIVE AGENTS. Some of them are biosynthesized non-ribosomally (PEPTIDE BIOSYNTHESIS, NON-RIBOSOMAL).

Glomerulonephritis associated with autoimmune disease SYSTEMIC LUPUS ERYTHEMATOSUS. Lupus nephritis is histologically classified into 6 classes: class I - normal glomeruli, class II - pure mesangial alterations, class III - focal segmental glomerulonephritis, class IV - diffuse glomerulonephritis, class V - diffuse membranous glomerulonephritis, and class VI - advanced sclerosing glomerulonephritis (The World Health Organization classification 1982).

Autoantibodies directed against various nuclear antigens including DNA, RNA, histones, acidic nuclear proteins, or complexes of these molecular elements. Antinuclear antibodies are found in systemic autoimmune diseases including systemic lupus erythematosus, Sjogren's syndrome, scleroderma, polymyositis, and mixed connective tissue disease.

The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.

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.

Plasmids containing at least one cos (cohesive-end site) of PHAGE LAMBDA. They are used as cloning vehicles.

In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.

Proteins found in any species of bacterium.

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.

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 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.

Transport proteins that carry specific substances in the blood or across cell membranes.

Serum serine proteases which participate in COMPLEMENT ACTIVATION. They are activated when complexed with the MANNOSE-BINDING LECTIN, therefore also known as Mannose-binding protein-Associated Serine Proteases (MASPs). They cleave COMPLEMENT C4 and COMPLEMENT C2 to form C4b2a, the CLASSICAL PATHWAY C3 CONVERTASE.

A group of inherited disorders of the ADRENAL GLANDS, caused by enzyme defects in the synthesis of cortisol (HYDROCORTISONE) and/or ALDOSTERONE leading to accumulation of precursors for ANDROGENS. Depending on the hormone imbalance, congenital adrenal hyperplasia can be classified as salt-wasting, hypertensive, virilizing, or feminizing. Defects in STEROID 21-HYDROXYLASE; STEROID 11-BETA-HYDROXYLASE; STEROID 17-ALPHA-HYDROXYLASE; 3-beta-hydroxysteroid dehydrogenase (3-HYDROXYSTEROID DEHYDROGENASES); TESTOSTERONE 5-ALPHA-REDUCTASE; or steroidogenic acute regulatory protein; among others, underlie these disorders.

The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.

An individual in which both alleles at a given locus are identical.

Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.

The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.

Biologically active substances whose activities affect or play a role in the functioning of the immune system.

Elements of limited time intervals, contributing to particular results or situations.

The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.

Histochemical localization of immunoreactive substances using labeled antibodies as reagents.

The number of copies of a given gene present in the cell of an organism. An increase in gene dosage (by GENE DUPLICATION for example) can result in higher levels of gene product formation. GENE DOSAGE COMPENSATION mechanisms result in adjustments to the level GENE EXPRESSION when there are changes or differences in gene dosage.

The genetic constitution of individuals with respect to one member of a pair of allelic genes, or sets of genes that are closely linked and tend to be inherited together such as those of the MAJOR HISTOCOMPATIBILITY COMPLEX.

Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.

Antigens determined by leukocyte loci found on chromosome 6, the major histocompatibility loci in humans. They are polypeptides or glycoproteins found on most nucleated cells and platelets, determine tissue types for transplantation, and are associated with certain diseases.

Glycoproteins found on the membrane or surface of cells.

The sequential correspondence of nucleotides in one nucleic acid molecule with those of another nucleic acid molecule. Sequence homology is an indication of the genetic relatedness of different organisms and gene function.

The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.

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.

The sum of the weight of all the atoms in a molecule.

The rate dynamics in chemical or physical systems.

Plasma glycoprotein clotted by thrombin, composed of a dimer of three non-identical pairs of polypeptide chains (alpha, beta, gamma) held together by disulfide bonds. Fibrinogen clotting is a sol-gel change involving complex molecular arrangements: whereas fibrinogen is cleaved by thrombin to form polypeptides A and B, the proteolytic action of other enzymes yields different fibrinogen degradation products.

The parts of a transcript of a split GENE remaining after the INTRONS are removed. They are spliced together to become a MESSENGER RNA or other functional RNA.

Lymphoid cells concerned with humoral immunity. They are short-lived cells resembling bursa-derived lymphocytes of birds in their production of immunoglobulin upon appropriate stimulation.

The presence of proteins in the urine, an indicator of KIDNEY DISEASES.

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.

The production of ANTIBODIES by proliferating and differentiated B-LYMPHOCYTES under stimulation by ANTIGENS.

Any member of the group of ENDOPEPTIDASES containing at the active site a serine residue involved in catalysis.

A gram-positive organism found in the upper respiratory tract, inflammatory exudates, and various body fluids of normal and/or diseased humans and, rarely, domestic animals.

A class of C-type lectins that target the carbohydrate structures found on invading pathogens. Binding of collectins to microorganisms results in their agglutination and enhanced clearance. Collectins form trimers that may assemble into larger oligomers. Each collectin polypeptide chain consists of four regions: a relatively short N-terminal region, a collagen-like region, an alpha-helical coiled-coil region, and carbohydrate-binding region.

Use of restriction endonucleases to analyze and generate a physical map of genomes, genes, or other segments of DNA.

A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms.

Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.

A plasma protein that circulates in increased amounts during inflammation and after tissue damage.

The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.

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.

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)

Cytochrome P-450 monooxygenases (MIXED FUNCTION OXYGENASES) that are important in steroid biosynthesis and metabolism.

Detection of RNA that has been electrophoretically separated and immobilized by blotting on nitrocellulose or other type of paper or nylon membrane followed by hybridization with labeled NUCLEIC ACID PROBES.

Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.

Single-stranded complementary DNA synthesized from an RNA template by the action of RNA-dependent DNA polymerase. cDNA (i.e., complementary DNA, not circular DNA, not C-DNA) is used in a variety of molecular cloning experiments as well as serving as a specific hybridization probe.

A method (first developed by E.M. Southern) for detection of DNA that has been electrophoretically separated and immobilized by blotting on nitrocellulose or other type of paper or nylon membrane followed by hybridization with labeled NUCLEIC ACID PROBES.

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.

Degenerative changes in the RETINA usually of older adults which results in a loss of vision in the center of the visual field (the MACULA LUTEA) because of damage to the retina. It occurs in dry and wet forms.

A constitution or condition of the body which makes the tissues react in special ways to certain extrinsic stimuli and thus tends to make the individual more than usually susceptible to certain diseases.

Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.

A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis.

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.

The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.

The record of descent or ancestry, particularly of a particular condition or trait, indicating individual family members, their relationships, and their status with respect to the trait or condition.

Studies which start with the identification of persons with a disease of interest and a control (comparison, referent) group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.

Variation occurring within a species in the presence or length of DNA fragment generated by a specific endonuclease at a specific site in the genome. Such variations are generated by mutations that create or abolish recognition sites for these enzymes or change the length of the fragment.

The proportion of one particular in the total of all ALLELES for one genetic locus in a breeding POPULATION.

A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.

A method for the detection of very small quantities of antibody in which the antigen-antibody-complement complex adheres to indicator cells, usually primate erythrocytes or nonprimate blood platelets. The reaction is dependent on the number of bound C3 molecules on the C3b receptor sites of the indicator cell.

A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.

A technique that combines protein electrophoresis and double immunodiffusion. In this procedure proteins are first separated by gel electrophoresis (usually agarose), then made visible by immunodiffusion of specific antibodies. A distinct elliptical precipitin arc results for each protein detectable by the antisera.

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 uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.

A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.

Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.

A chronic systemic disease, primarily of the joints, marked by inflammatory changes in the synovial membranes and articular structures, widespread fibrinoid degeneration of the collagen fibers in mesenchymal tissues, and by atrophy and rarefaction of bony structures. Etiology is unknown, but autoimmune mechanisms have been implicated.

Immunoglobulins produced in a response to BACTERIAL ANTIGENS.

The systematic study of the complete complement of proteins (PROTEOME) of organisms.

Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.

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 characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).

Cells that line the inner and outer surfaces of the body by forming cellular layers (EPITHELIUM) or masses. Epithelial cells lining the SKIN; the MOUTH; the NOSE; and the ANAL CANAL derive from ectoderm; those lining the RESPIRATORY SYSTEM and the DIGESTIVE SYSTEM derive from endoderm; others (CARDIOVASCULAR SYSTEM and LYMPHATIC SYSTEM) derive from mesoderm. Epithelial cells can be classified mainly by cell shape and function into squamous, glandular and transitional epithelial cells.

The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.

A large collection of DNA fragments cloned (CLONING, MOLECULAR) from a given organism, tissue, organ, or cell type. It may contain complete genomic sequences (GENOMIC LIBRARY) or complementary DNA sequences, the latter being formed from messenger RNA and lacking intron sequences.

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 latent susceptibility to disease at the genetic level, which may be activated under certain conditions.

A condition characterized by the recurrence of HEMOGLOBINURIA caused by intravascular HEMOLYSIS. In cases occurring upon cold exposure (paroxysmal cold hemoglobinuria), usually after infections, there is a circulating antibody which is also a cold hemolysin. In cases occurring during or after sleep (paroxysmal nocturnal hemoglobinuria), the clonal hematopoietic stem cells exhibit a global deficiency of cell membrane proteins.

A single nucleotide variation in a genetic sequence that occurs at appreciable frequency in the population.

Group of diseases mediated by the deposition of large soluble complexes of antigen and antibody with resultant damage to tissue. Besides SERUM SICKNESS and the ARTHUS REACTION, evidence supports a pathogenic role for immune complexes in many other IMMUNE SYSTEM DISEASES including GLOMERULONEPHRITIS, systemic lupus erythematosus (LUPUS ERYTHEMATOSUS, SYSTEMIC) and POLYARTERITIS NODOSA.

Chimeric receptors of the human C3a receptor and C5a receptor (CD88). (1/332)

Chimeras were generated between the human anaphylatoxin C3a and C5a receptors (C3aR and C5aR, respectively) to define the structural requirements for ligand binding and discrimination. Chimeric receptors were generated by systematically exchanging between the two receptors four receptor modules (the N terminus, transmembrane regions 1 to 4, the second extracellular loop, and transmembrane region 5 to the C terminus). The mutants were transiently expressed in HEK-293 cells (with or without Galpha-16) and analyzed for cell surface expression, binding of C3a and C5a, and functional responsiveness (calcium mobilization) toward C3a, C5a, and a C3a as well as a C5a analogue peptide. The data indicate that in both anaphylatoxin receptors the transmembrane regions and the second extracellular loop act as a functional unit that is disrupted by any reciprocal exchange. N-terminal substitution confirmed the two-binding site model for the human C5aR, in which the receptor N terminus is required for high affinity binding of the native ligand but not a C5a analogue peptide. In contrast, the human C3a receptor did not require the original N terminus for high affinity binding of and activation by C3a, a result that was confirmed by N-terminal deletion mutants. This indicates a completely different binding mode of the anaphylatoxins to their corresponding receptors. The C5a analogue peptide, but not C5a, was an agonist of the C3aR. Replacement of the C3aR N terminus by the C5aR sequence, however, lead to the generation of a true hybrid C3a/C5a receptor, which bound and functionally responded to both ligands, C3a and C5a. (+info)

Regional specificity of ASP binding in human adipose tissue. (2/332)

Obesity, in particular omental (OM) adiposity, is associated with diabetes and cardiovascular disease. Thus site-specific regulation of fat storage is important to understand. Acylation-stimulating protein (ASP) is a potent stimulator of glucose transport and triglyceride synthesis in adipocytes. In the present study, we characterized receptor binding of 125I-labeled ASP to human adipocyte plasma membranes from paired OM and subcutaneous (SC) sites in normal (N) and obese (O) male (M) and female (F) subjects (n = 24). Overall, specific binding of 125I-ASP was in the order of SC > OM and O > N (in SC tissue, particularly in F). Receptor affinity of 125I-ASP was higher [lower dissociation constant (Kd)] in SC than in OM (63.6 +/- 16.2 vs. 160.7 +/- 38.6 nM, P < 0.02), especially in F (37.0 +/- 11.1 F-N and 26.3 +/- 6.7 nM F-O) and lower (higher Kd) in male OM (291.8 +/- 116.8 M-N and 149.4 +/- 56.4 M-O). The greater binding and higher affinity of 125I-ASP binding to SC suggests that ASP may be an important factor in maintaining regional adipose tissue mass. Conversely, lower binding and receptor affinity in male OM adipose tissue may contribute to the fatty acid imbalance and metabolic complications associated with this syndrome, by reducing the efficiency of adipose fatty acid trapping by the ASP pathway. (+info)

Effect of permeability on indices of haemodialysis membrane biocompatibility. (3/332)

BACKGROUND: Increases in plasma anaphylatoxins frequently are used as an index of haemodialysis membrane biocompatibility; however, their plasma levels may be influenced by the loss of anaphylatoxins into the dialysate compartment. METHODS: We compared the generation and compartmental distribution of anaphylatoxins, C3a and C5a, in a high flux and a low flux polysulfone membrane dialyser when whole human blood was recirculated through an in vitro haemodialysis circuit. RESULTS: Plasma C3a levels in high flux polysulfone (2.31 +/- 0.81 microg/ml) and low flux polysulfone (3.02 +/- 0.98 microg/ml) dialysers were comparable after 120 min (P = NS). In contrast, dialysate C3a in high flux polysulfone (0.65 +/- 0.31 microg/ml) accounted for 37.5 +/- 7.0% of the total detected (plasma + dialysate) C3a mass in the dialysers, while dialysate C3a in low flux polysulfone dialysers (0.01 +/- 0.01 microg/ml) accounted for only 0.3 +/- 0.3% of the total mass (P < 0.05; high flux vs low flux). Anaphylatoxin C5a was undetectable in the dialysate compartment of either dialyser examined. CONCLUSIONS: Our results indicate that anaphylatoxins readily traverse certain high flux dialysis membranes; consequently, plasma C3a levels may not accurately reflect the C3-activating potential of these membranes. (+info)

Modulation of C3a activity: internalization of the human C3a receptor and its inhibition by C5a. (4/332)

The C3a receptor (C3aR) is expressed on most human peripheral blood leukocytes with the exception of resting lymphocytes, implying a much higher pathophysiological relevance of the anaphylatoxin C3a as a proinflammatory mediator than previously thought. The response to this complement split product must be tightly regulated in situations with sustained complement activation to avoid deleterious effects caused by overactivated inflammatory cells. Receptor internalization, an important control mechanism described for G protein-coupled receptors, was investigated. Using rabbit polyclonal anti-serum directed against the C3aR second extracellular loop, a flow cytometry-based receptor internalization assay was developed. Within minutes of C3a addition to human granulocytes, C3aR almost completely disappeared from the cell surface. C3aR internalization could also be induced by PMA, an activator of protein kinase C. Similarly, monocytes, the human mast cell line HMC-1, and differentiated monocyte/macrophage-like U937-cells exhibited rapid agonist-dependent receptor internalization. Neither C5a nor FMLP stimulated any cross-internalization of the C3aR. On the contrary, costimulation of granulocytes with C5a, but not FMLP, drastically decreased C3aR internalization. This effect could be blocked by a C5aR-neutralizing mAb. HEK293-cells transfected with the C3aR, with or without Galpha16, a pertussis toxin-resistant G protein alpha subunit required for C3aR signal transduction in these cells, did not exhibit agonist-dependent C3aR internalization. Additionally, preincubation with pertussis toxin had no effect on C3a-induced internalization on PMNs. C3aR internalization is a rapid negative control mechanism and is influenced by the C5aR pathway. (+info)

Mechanisms involved in the regulation of free fatty acid release from isolated human fat cells by acylation-stimulating protein and insulin. (5/332)

The effects of acylation-stimulating protein (ASP) and insulin on free fatty acid (FFA) release from isolated human fat cells and the signal transduction pathways to induce these effects were studied. ASP and insulin inhibited basal and norepinephrine-induced FFA release by stimulating fractional FFA re-esterification (both to the same extent) and by inhibiting FFA produced during lipolysis (ASP to a lesser extent than insulin). Protein kinase C inhibition influenced none of the effects of ASP or insulin. Phosphatidylinositol 3-kinase inhibition counteracted the effects of insulin but not of ASP. Phosphodiesterase 3 (PDE3) activity was stimulated by ASP and insulin, whereas PDE4 activity was slightly increased by ASP only. Selective PDE3 inhibition reversed the effects of both ASP and insulin on fractional FFA re-esterification and lipolysis. Selective PDE4 inhibition slightly counteracted the ASP but not the effect of insulin on fractional FFA re-esterification and did not prevent the action of ASP or insulin on lipolysis. Thus, ASP and insulin play a major role in regulating FFA release from fat cells as follows: insulin by stimulating fractional FFA re-esterification and inhibiting lipolysis and ASP mainly by stimulating fractional FFA re-esterification. For both ASP and insulin these effects on FFA release are mediated by PDE3, and for ASP PDE4 might also be involved. The signaling pathway preceding PDE is not known for ASP but involves phosphatidylinositol 3-kinase for insulin. (+info)

Genetic deficiency of acylation stimulating protein (ASP(C3ades-Arg)) does not cause hyperapobetalipoproteinemia in mice. (6/332)

The acylation stimulating protein (ASP) is a 76-amino acid peptide that has been proposed as a potent mediator of triglyceride synthesis and, when functionally impaired, as a major cause of hyperapobetalipoproteinemia (HyperapoB). Purification and sequence analysis of ASP from human sera have revealed that ASP is identical to the complement C3-derived activation peptide C3ades-Arg. Because C3 is the precursor for C3ades-Arg and therefore ASP, a deficiency in C3 would be predicted to result in a phenotype characteristic of HyperapoB. To test this hypothesis in vivo, the current study was undertaken in which ASP(C3ades-Arg)-deficient mice were used as a model system. No significant differences were found in the triglyceride, cholesterol, or free fatty acid concentrations in the plasma of fasted normal and ASP(C3ades-Arg)-deficient animals. In addition, plasma lipoprotein analyses indicated that the very low density lipoprotein, low density lipoprotein, and high density lipoprotein cholesterol and triglyceride concentrations as well as the apolipoprotein B-48 and B-100 levels were not significantly different in the plasma of ASP(C3ades-Arg)-deficient and wild type mice. Furthermore, when challenged with an oral fat load, the ASP(C3ades-Arg)-deficient mice showed no impaired ability to clear triglycerides and free fatty acids from their circulation when compared with their wild-type littermates. Collectively, these results indicate that ASP(C3ades-Arg) deficiency does not cause HyperapoB in mice and that the physiological importance of impaired ASP(C3ades-Arg) function as a cause of hyperapobetalipoproteinemia needs to be reevaluated. (+info)

Role of C3 cleavage in monocyte activation during extracorporeal circulation. (7/332)

BACKGROUND: We previously demonstrated that inhibiting formation of terminal complement components (C5a and C5b-9) prevents platelet and neutrophil (PMN) but not monocyte activation during simulated extracorporeal circulation (SECC). This study examined whether earlier complement inhibition during SECC, blocking C3a formation, would additionally prevent monocyte activation. METHODS AND RESULTS: SECC was established by recirculating heparinized whole blood from human volunteers on a membrane oxygenator. CAB-2, a chimeric protein constructed from genes encoding the complement regulatory proteins CD46 and CD55, inactivates the C3/C5 convertases and blocks in vitro generation of C3a, C5a, and C5b-9. CAB-2 was used in 4 experiments at a final concentration of 300 micrograms/mL and 4 experiments at 30 micrograms/mL; 4 control runs used vehicle alone. Samples were assayed for C3a and C5b-9, monocyte activation (CD11b upregulation), PMN activation (CD11b upregulation and elastase release), and platelet activation (P-selectin expression and monocyte-platelet conjugate formation). CAB-2 at both doses significantly inhibited formation of C3a and C5b-9 during SECC. High-dose CAB-2 significantly blocked monocyte and PMN CD11b upregulation and PMN elastase release. CAB-2 also inhibited formation of platelet activation-dependent monocyte-platelet conjugates. CONCLUSIONS: Blockade of complement activation early in the common pathway inhibited monocyte CD11b upregulation during SECC, suggesting that early complement components contribute most to monocyte activation during SECC. As expected, PMN and platelet activation were blocked by terminal complement inhibition. This investigation further elucidates the relation between complement and blood cell activation during simulated cardiopulmonary bypass. (+info)

Possible mechanism for in vitro complement activation in blood and plasma samples: futhan/EDTA controls in vitro complement activation. (8/332)

BACKGROUND: Ongoing in vitro complement (C) activation in citrate or EDTA plasma has prevented an accurate analysis of C-activation products generated in vivo. The aim of this study was to characterize handling and storage conditions required to prevent in vitro C activation in blood and plasma samples collected with Futhan/EDTA. METHODS: Biotrak(TM) RIAs were used to quantitatively measure C3a and C4a in blood and/or plasma samples from healthy individuals (controls) and from liver transplant patients. Blood samples were routinely drawn into either EDTA (1 g/L) tubes or into tubes containing both EDTA (1 g/L) and Futhan (0.1 g/L) and immediately centrifuged at 2000g for 15 min at 4 degrees C. RESULTS: In controls, C4a, but not C3a, in fresh samples (time 0) was higher in EDTA plasma than in Futhan/EDTA plasma (n = 20; P = 0.002). Futhan/EDTA prevented C3a and C4a generation in blood and plasma samples held at room temperature (22-23 degrees C) for 1 h and in plasma held for 24 h at 4 degrees C or -70 degrees C. The mean C3a concentration (1.76 mg/L; n = 19) at time 0 in EDTA plasma samples from liver transplant patients was significantly higher than for controls (0.34 mg/L; n = 11). In these patients, the mean C3a in EDTA samples increased to 13.8 mg/L after 60 min at room temperature, but there was no change in the C3a concentration of an EDTA plasma from a control. In the patients, C3a concentrations were lower in Futhan/EDTA plasma than in EDTA at time 0 and after 60 min at room temperature (1.40 and 2.02 mg/L, respectively). The mean patient C4a was 4.02 mg/L in EDTA plasma at time 0 vs 0.24 mg/L for controls; it increased to 16.9 mg/L after 60 min at room temperature compared with 0.76 mg/L for controls. The mean patient C4a was 0.83 mg/L in Futhan/EDTA plasma at time 0 vs 0.1 mg/L for controls. Neither patient nor control C4a concentrations increased vs time in Futhan/EDTA. CONCLUSION: The combination of Futhan (0.1 g/L) and EDTA (1 g/L) eliminates in vitro C activation. (+info)

There are two main types of hemolysis:

1. Intravascular hemolysis: This type occurs within the blood vessels and is caused by factors such as mechanical injury, oxidative stress, and certain infections.
2. Extravascular hemolysis: This type occurs outside the blood vessels and is caused by factors such as bone marrow disorders, splenic rupture, and certain medications.

Hemolytic anemia is a condition that occurs when there is excessive hemolysis of RBCs, leading to a decrease in the number of healthy red blood cells in the body. This can cause symptoms such as fatigue, weakness, pale skin, and shortness of breath.

Some common causes of hemolysis include:

1. Genetic disorders such as sickle cell anemia and thalassemia.
2. Autoimmune disorders such as autoimmune hemolytic anemia (AIHA).
3. Infections such as malaria, babesiosis, and toxoplasmosis.
4. Medications such as antibiotics, nonsteroidal anti-inflammatory drugs (NSAIDs), and blood thinners.
5. Bone marrow disorders such as aplastic anemia and myelofibrosis.
6. Splenic rupture or surgical removal of the spleen.
7. Mechanical injury to the blood vessels.

Diagnosis of hemolysis is based on a combination of physical examination, medical history, and laboratory tests such as complete blood count (CBC), blood smear examination, and direct Coombs test. Treatment depends on the underlying cause and may include supportive care, blood transfusions, and medications to suppress the immune system or prevent infection.

The term "systemic" refers to the fact that the disease affects multiple organ systems, including the skin, joints, kidneys, lungs, and nervous system. LES is a complex condition, and its symptoms can vary widely depending on which organs are affected. Common symptoms include fatigue, fever, joint pain, rashes, and swelling in the extremities.

There are several subtypes of LES, including:

1. Systemic lupus erythematosus (SLE): This is the most common form of the disease, and it can affect anyone, regardless of age or gender.
2. Discoid lupus erythematosus (DLE): This subtype typically affects the skin, causing a red, scaly rash that does not go away.
3. Drug-induced lupus erythematosus: This form of the disease is caused by certain medications, and it usually resolves once the medication is stopped.
4. Neonatal lupus erythematosus: This rare condition affects newborn babies of mothers with SLE, and it can cause liver and heart problems.

There is no cure for LES, but treatment options are available to manage the symptoms and prevent flares. Treatment may include nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, immunosuppressive medications, and antimalarial drugs. In severe cases, hospitalization may be necessary to monitor and treat the disease.

It is important for people with LES to work closely with their healthcare providers to manage their condition and prevent complications. With proper treatment and self-care, many people with LES can lead active and fulfilling lives.

Idiopathic membranous nephropathy (IMN) is an autoimmune disorder that causes GNM without any identifiable cause. Secondary membranous nephropathy, on the other hand, is caused by systemic diseases such as lupus or cancer.

The symptoms of GNM can vary depending on the severity of the disease and may include blood in the urine, proteinuria, edema, high blood pressure, and decreased kidney function. The diagnosis of GNM is based on a combination of clinical findings, laboratory tests, and renal biopsy.

Treatment for GNM is aimed at slowing the progression of the disease and managing symptoms. Medications such as corticosteroids, immunosuppressive drugs, and blood pressure-lowering drugs may be used to treat GNM. In some cases, kidney transplantation may be necessary.

The prognosis for GNM varies depending on the severity of the disease and the underlying cause. In general, the prognosis for IMN is better than for secondary membranous nephropathy. With proper treatment, some patients with GNM can experience a slowing or stabilization of the disease, while others may progress to end-stage renal disease (ESRD).

The cause of GNM is not fully understood, but it is believed to be an autoimmune disorder that leads to inflammation and damage to the glomerular membrane. Genetic factors and environmental triggers may also play a role in the development of GNM.

There are several risk factors for developing GNM, including family history, age (GMN is more common in adults), and certain medical conditions such as hypertension and diabetes.

The main complications of GNM include:

1. ESRD: Progression to ESRD is a common outcome of untreated GNM.
2. High blood pressure: GNM can lead to high blood pressure, which can further damage the kidneys.
3. Infections: GNM increases the risk of infections due to impaired immune function.
4. Kidney failure: GNM can cause chronic kidney failure, leading to the need for dialysis or a kidney transplant.
5. Cardiovascular disease: GNM is associated with an increased risk of cardiovascular disease, including heart attack and stroke.
6. Malnutrition: GNM can lead to malnutrition due to decreased appetite, nausea, and vomiting.
7. Bone disease: GNM can cause bone disease, including osteoporosis and bone pain.
8. Anemia: GNM can cause anemia, which can lead to fatigue, weakness, and shortness of breath.
9. Increased risk of infections: GNM increases the risk of infections due to impaired immune function.
10. Decreased quality of life: GNM can significantly decrease a person's quality of life, leading to decreased mobility, pain, and discomfort.

It is important for individuals with GNM to receive early diagnosis and appropriate treatment to prevent or delay the progression of these complications.

The symptoms of glomerulonephritis can vary depending on the underlying cause of the disease, but may include:

* Blood in the urine (hematuria)
* Proteinuria (excess protein in the urine)
* Reduced kidney function
* Swelling in the legs and ankles (edema)
* High blood pressure

Glomerulonephritis can be caused by a variety of factors, including:

* Infections such as staphylococcal or streptococcal infections
* Autoimmune disorders such as lupus or rheumatoid arthritis
* Allergic reactions to certain medications
* Genetic defects
* Certain diseases such as diabetes, high blood pressure, and sickle cell anemia

The diagnosis of glomerulonephritis typically involves a physical examination, medical history, and laboratory tests such as urinalysis, blood tests, and kidney biopsy.

Treatment for glomerulonephritis depends on the underlying cause of the disease and may include:

* Antibiotics to treat infections
* Medications to reduce inflammation and swelling
* Diuretics to reduce fluid buildup in the body
* Immunosuppressive medications to suppress the immune system in cases of autoimmune disorders
* Dialysis in severe cases

The prognosis for glomerulonephritis depends on the underlying cause of the disease and the severity of the inflammation. In some cases, the disease may progress to end-stage renal disease, which requires dialysis or a kidney transplant. With proper treatment, however, many people with glomerulonephritis can experience a good outcome and maintain their kidney function over time.

Arteriolosclerosis is often associated with conditions such as hypertension, diabetes, and atherosclerosis, which is the buildup of plaque in the arteries. It can also be caused by other factors such as smoking, high cholesterol levels, and inflammation.

The symptoms of arteriolosclerosis can vary depending on the location and severity of the condition, but may include:

* Decreased blood flow to organs or tissues
* Fatigue
* Weakness
* Shortness of breath
* Dizziness or lightheadedness
* Pain in the affected limbs or organs

Arteriolosclerosis is typically diagnosed through a combination of physical examination, medical history, and diagnostic tests such as ultrasound, angiography, or blood tests. Treatment for the condition may include lifestyle changes such as exercise and dietary modifications, medications to control risk factors such as hypertension and high cholesterol, and in some cases, surgical intervention to open or bypass blocked arterioles.

In summary, arteriolosclerosis is a condition where the arterioles become narrowed or obstructed, leading to decreased blood flow to organs and tissues and potentially causing a range of health problems. It is often associated with other conditions such as hypertension and atherosclerosis, and can be diagnosed through a combination of physical examination, medical history, and diagnostic tests. Treatment may include lifestyle changes and medications to control risk factors, as well as surgical intervention in some cases.

1) They share similarities with humans: Many animal species share similar biological and physiological characteristics with humans, making them useful for studying human diseases. For example, mice and rats are often used to study diseases such as diabetes, heart disease, and cancer because they have similar metabolic and cardiovascular systems to humans.

2) They can be genetically manipulated: Animal disease models can be genetically engineered to develop specific diseases or to model human genetic disorders. This allows researchers to study the progression of the disease and test potential treatments in a controlled environment.

3) They can be used to test drugs and therapies: Before new drugs or therapies are tested in humans, they are often first tested in animal models of disease. This allows researchers to assess the safety and efficacy of the treatment before moving on to human clinical trials.

4) They can provide insights into disease mechanisms: Studying disease models in animals can provide valuable insights into the underlying mechanisms of a particular disease. This information can then be used to develop new treatments or improve existing ones.

5) Reduces the need for human testing: Using animal disease models reduces the need for human testing, which can be time-consuming, expensive, and ethically challenging. However, it is important to note that animal models are not perfect substitutes for human subjects, and results obtained from animal studies may not always translate to humans.

6) They can be used to study infectious diseases: Animal disease models can be used to study infectious diseases such as HIV, TB, and malaria. These models allow researchers to understand how the disease is transmitted, how it progresses, and how it responds to treatment.

7) They can be used to study complex diseases: Animal disease models can be used to study complex diseases such as cancer, diabetes, and heart disease. These models allow researchers to understand the underlying mechanisms of the disease and test potential treatments.

8) They are cost-effective: Animal disease models are often less expensive than human clinical trials, making them a cost-effective way to conduct research.

9) They can be used to study drug delivery: Animal disease models can be used to study drug delivery and pharmacokinetics, which is important for developing new drugs and drug delivery systems.

10) They can be used to study aging: Animal disease models can be used to study the aging process and age-related diseases such as Alzheimer's and Parkinson's. This allows researchers to understand how aging contributes to disease and develop potential treatments.

There are several types of lupus nephritis, each with its own unique characteristics and symptoms. The most common forms include:

* Class I (mesangial proliferative glomerulonephritis): This type is characterized by the growth of abnormal cells in the glomeruli (blood-filtering units of the kidneys).
* Class II (active lupus nephritis): This type is characterized by widespread inflammation and damage to the kidneys, with or without the presence of antibodies.
* Class III (focal lupus nephritis): This type is characterized by localized inflammation in certain areas of the kidneys.
* Class IV (lupus nephritis with crescentic glomerulonephritis): This type is characterized by widespread inflammation and damage to the kidneys, with crescent-shaped tissue growth in the glomeruli.
* Class V (lupus nephritis with sclerotic changes): This type is characterized by hardening and shrinkage of the glomeruli due to scarring.

Lupus Nephritis can cause a range of symptoms, including:

* Proteinuria (excess protein in the urine)
* Hematuria (blood in the urine)
* Reduced kidney function
* Swelling (edema)
* Fatigue
* Fever
* Joint pain

Lupus Nephritis can be diagnosed through a combination of physical examination, medical history, laboratory tests, and kidney biopsy. Treatment options for lupus nephritis include medications to suppress the immune system, control inflammation, and prevent further damage to the kidneys. In severe cases, dialysis or a kidney transplant may be necessary.

There are several key features of inflammation:

1. Increased blood flow: Blood vessels in the affected area dilate, allowing more blood to flow into the tissue and bringing with it immune cells, nutrients, and other signaling molecules.
2. Leukocyte migration: White blood cells, such as neutrophils and monocytes, migrate towards the site of inflammation in response to chemical signals.
3. Release of mediators: Inflammatory mediators, such as cytokines and chemokines, are released by immune cells and other cells in the affected tissue. These molecules help to coordinate the immune response and attract more immune cells to the site of inflammation.
4. Activation of immune cells: Immune cells, such as macrophages and T cells, become activated and start to phagocytose (engulf) pathogens or damaged tissue.
5. Increased heat production: Inflammation can cause an increase in metabolic activity in the affected tissue, leading to increased heat production.
6. Redness and swelling: Increased blood flow and leakiness of blood vessels can cause redness and swelling in the affected area.
7. Pain: Inflammation can cause pain through the activation of nociceptors (pain-sensing neurons) and the release of pro-inflammatory mediators.

Inflammation can be acute or chronic. Acute inflammation is a short-term response to injury or infection, which helps to resolve the issue quickly. Chronic inflammation is a long-term response that can cause ongoing damage and diseases such as arthritis, asthma, and cancer.

There are several types of inflammation, including:

1. Acute inflammation: A short-term response to injury or infection.
2. Chronic inflammation: A long-term response that can cause ongoing damage and diseases.
3. Autoimmune inflammation: An inappropriate immune response against the body's own tissues.
4. Allergic inflammation: An immune response to a harmless substance, such as pollen or dust mites.
5. Parasitic inflammation: An immune response to parasites, such as worms or fungi.
6. Bacterial inflammation: An immune response to bacteria.
7. Viral inflammation: An immune response to viruses.
8. Fungal inflammation: An immune response to fungi.

There are several ways to reduce inflammation, including:

1. Medications such as nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, and disease-modifying anti-rheumatic drugs (DMARDs).
2. Lifestyle changes, such as a healthy diet, regular exercise, stress management, and getting enough sleep.
3. Alternative therapies, such as acupuncture, herbal supplements, and mind-body practices.
4. Addressing underlying conditions, such as hormonal imbalances, gut health issues, and chronic infections.
5. Using anti-inflammatory compounds found in certain foods, such as omega-3 fatty acids, turmeric, and ginger.

It's important to note that chronic inflammation can lead to a range of health problems, including:

1. Arthritis
2. Diabetes
3. Heart disease
4. Cancer
5. Alzheimer's disease
6. Parkinson's disease
7. Autoimmune disorders, such as lupus and rheumatoid arthritis.

Therefore, it's important to manage inflammation effectively to prevent these complications and improve overall health and well-being.

There are three main forms of ACH:

1. Classic congenital adrenal hyperplasia (CAH): This is the most common form of ACH, accounting for about 90% of cases. It is caused by mutations in the CYP21 gene, which codes for an enzyme that converts cholesterol into cortisol and aldosterone.
2. Non-classic CAH (NCAH): This form of ACH is less common than classic CAH and is caused by mutations in other genes involved in cortisol and aldosterone production.
3. Mineralocorticoid excess (MOE) or glucocorticoid deficiency (GD): These are rare forms of ACH that are characterized by excessive production of mineralocorticoids (such as aldosterone) or a deficiency of glucocorticoids (such as cortisol).

The symptoms of ACH can vary depending on the specific form of the disorder and the age at which it is diagnosed. In classic CAH, symptoms typically appear in infancy and may include:

* Premature puberty (in girls) or delayed puberty (in boys)
* Abnormal growth patterns
* Distended abdomen
* Fatigue
* Weight gain or obesity
* Easy bruising or bleeding

In NCAH and MOE/GD, symptoms may be less severe or may not appear until later in childhood or adulthood. They may include:

* High blood pressure
* Low blood sugar (hypoglycemia)
* Weight gain or obesity
* Fatigue
* Mood changes

If left untreated, ACH can lead to serious complications, including:

* Adrenal gland insufficiency
* Heart problems
* Bone health problems
* Increased risk of infections
* Mental health issues (such as depression or anxiety)

Treatment for ACH typically involves hormone replacement therapy to restore the balance of hormones in the body. This may involve taking medications such as cortisol, aldosterone, or other hormones to replace those that are deficient or imbalanced. In some cases, surgery may be necessary to remove an adrenal tumor or to correct physical abnormalities.

With proper treatment, many individuals with ACH can lead healthy, active lives. However, it is important for individuals with ACH to work closely with their healthcare providers to manage their condition and prevent complications. This may involve regular check-ups, hormone level monitoring, and lifestyle changes such as a healthy diet and regular exercise.

Proteinuria is usually diagnosed by a urine protein-to-creatinine ratio (P/C ratio) or a 24-hour urine protein collection. The amount and duration of proteinuria can help distinguish between different underlying causes and predict prognosis.

Proteinuria can have significant clinical implications, as it is associated with increased risk of cardiovascular disease, kidney damage, and malnutrition. Treatment of the underlying cause can help reduce or eliminate proteinuria.

There are two main types of MD:

1. Dry Macular Degeneration (DMD): This is the most common form of MD, accounting for about 90% of cases. It is caused by the gradual accumulation of waste material in the macula, which can lead to cell death and vision loss over time.
2. Wet Macular Degeneration (WMD): This type of MD is less common but more aggressive, accounting for about 10% of cases. It occurs when new blood vessels grow underneath the retina, leaking fluid and causing damage to the macula. This can lead to rapid vision loss if left untreated.

The symptoms of MD can vary depending on the severity and type of the condition. Common symptoms include:

* Blurred vision
* Distorted vision (e.g., straight lines appearing wavy)
* Difficulty reading or recognizing faces
* Difficulty adjusting to bright light
* Blind spots in central vision

MD can have a significant impact on daily life, making it difficult to perform everyday tasks such as driving, reading, and recognizing faces.

There is currently no cure for MD, but there are several treatment options available to slow down the progression of the disease and manage its symptoms. These include:

* Anti-vascular endothelial growth factor (VEGF) injections: These medications can help prevent the growth of new blood vessels and reduce inflammation in the macula.
* Photodynamic therapy: This involves the use of a light-sensitive drug and low-intensity laser to damage and shrink the abnormal blood vessels in the macula.
* Vitamin supplements: Certain vitamins, such as vitamin C, E, and beta-carotene, have been shown to slow down the progression of MD.
* Laser surgery: This can be used to reduce the number of abnormal blood vessels in the macula and improve vision.

It is important for individuals with MD to receive regular monitoring and treatment from an eye care professional to manage their condition and prevent complications.

There are several types of disease susceptibility, including:

1. Genetic predisposition: This refers to the inherent tendency of an individual to develop a particular disease due to their genetic makeup. For example, some families may have a higher risk of developing certain diseases such as cancer or heart disease due to inherited genetic mutations.
2. Environmental susceptibility: This refers to the increased risk of developing a disease due to exposure to environmental factors such as pollutants, toxins, or infectious agents. For example, someone who lives in an area with high levels of air pollution may be more susceptible to developing respiratory problems.
3. Lifestyle susceptibility: This refers to the increased risk of developing a disease due to unhealthy lifestyle choices such as smoking, lack of exercise, or poor diet. For example, someone who smokes and is overweight may be more susceptible to developing heart disease or lung cancer.
4. Immune system susceptibility: This refers to the increased risk of developing a disease due to an impaired immune system. For example, people with autoimmune disorders such as HIV/AIDS or rheumatoid arthritis may be more susceptible to opportunistic infections.

Understanding disease susceptibility can help healthcare providers identify individuals who are at risk of developing certain diseases and provide preventive measures or early intervention to reduce the risk of disease progression. Additionally, genetic testing can help identify individuals with a high risk of developing certain diseases, allowing for earlier diagnosis and treatment.

In summary, disease susceptibility refers to the predisposition of an individual to develop a particular disease or condition due to various factors such as genetics, environment, lifestyle choices, and immune system function. Understanding disease susceptibility can help healthcare providers identify individuals at risk and provide appropriate preventive measures or early intervention to reduce the risk of disease progression.

There are several symptoms of RA, including:

1. Joint pain and stiffness, especially in the hands and feet
2. Swollen and warm joints
3. Redness and tenderness in the affected areas
4. Fatigue, fever, and loss of appetite
5. Loss of range of motion in the affected joints
6. Firm bumps of tissue under the skin (rheumatoid nodules)

RA can be diagnosed through a combination of physical examination, medical history, blood tests, and imaging studies such as X-rays or ultrasound. Treatment typically involves a combination of medications, including nonsteroidal anti-inflammatory drugs (NSAIDs), disease-modifying anti-rheumatic drugs (DMARDs), and biologic agents. Lifestyle modifications such as exercise and physical therapy can also be helpful in managing symptoms and improving quality of life.

There is no cure for RA, but early diagnosis and aggressive treatment can help to slow the progression of the disease and reduce symptoms. With proper management, many people with RA are able to lead active and fulfilling lives.

Explanation: Genetic predisposition to disease is influenced by multiple factors, including the presence of inherited genetic mutations or variations, environmental factors, and lifestyle choices. The likelihood of developing a particular disease can be increased by inherited genetic mutations that affect the functioning of specific genes or biological pathways. For example, inherited mutations in the BRCA1 and BRCA2 genes increase the risk of developing breast and ovarian cancer.

The expression of genetic predisposition to disease can vary widely, and not all individuals with a genetic predisposition will develop the disease. Additionally, many factors can influence the likelihood of developing a particular disease, such as environmental exposures, lifestyle choices, and other health conditions.

Inheritance patterns: Genetic predisposition to disease can be inherited in an autosomal dominant, autosomal recessive, or multifactorial pattern, depending on the specific disease and the genetic mutations involved. Autosomal dominant inheritance means that a single copy of the mutated gene is enough to cause the disease, while autosomal recessive inheritance requires two copies of the mutated gene. Multifactorial inheritance involves multiple genes and environmental factors contributing to the development of the disease.

Examples of diseases with a known genetic predisposition:

1. Huntington's disease: An autosomal dominant disorder caused by an expansion of a CAG repeat in the Huntingtin gene, leading to progressive neurodegeneration and cognitive decline.
2. Cystic fibrosis: An autosomal recessive disorder caused by mutations in the CFTR gene, leading to respiratory and digestive problems.
3. BRCA1/2-related breast and ovarian cancer: An inherited increased risk of developing breast and ovarian cancer due to mutations in the BRCA1 or BRCA2 genes.
4. Sickle cell anemia: An autosomal recessive disorder caused by a point mutation in the HBB gene, leading to defective hemoglobin production and red blood cell sickling.
5. Type 1 diabetes: An autoimmune disease caused by a combination of genetic and environmental factors, including multiple genes in the HLA complex.

Understanding the genetic basis of disease can help with early detection, prevention, and treatment. For example, genetic testing can identify individuals who are at risk for certain diseases, allowing for earlier intervention and preventive measures. Additionally, understanding the genetic basis of a disease can inform the development of targeted therapies and personalized medicine."

The disorder is caused by mutations in the HBB gene that codes for the beta-globin subunit of hemoglobin. These mutations result in the production of abnormal hemoglobins that are unstable and prone to breakdown, leading to the release of free hemoglobin into the urine.

HP is classified into two types based on the severity of symptoms:

1. Type 1 HP: This is the most common form of the disorder and is characterized by mild to moderate anemia, occasional hemoglobinuria, and a normal life expectancy.
2. Type 2 HP: This is a more severe form of the disorder and is characterized by severe anemia, recurrent hemoglobinuria, and a shorter life expectancy.

There is no cure for HP, but treatment options are available to manage symptoms and prevent complications. These may include blood transfusions, folic acid supplements, and medications to reduce the frequency and severity of hemoglobinuria episodes.

The term "immune complex disease" was first used in the 1960s to describe a group of conditions that were thought to be caused by the formation of immune complexes. These diseases include:

1. Systemic lupus erythematosus (SLE): an autoimmune disorder that can affect multiple organ systems and is characterized by the presence of anti-nuclear antibodies.
2. Rheumatoid arthritis (RA): an autoimmune disease that causes inflammation in the joints and can lead to joint damage.
3. Type III hypersensitivity reaction: a condition in which immune complexes are deposited in tissues, leading to inflammation and tissue damage.
4. Pemphigus: a group of autoimmune diseases that affect the skin and mucous membranes, characterized by the presence of autoantibodies against desmosomal antigens.
5. Bullous pemphigoid: an autoimmune disease that affects the skin and is characterized by the formation of large blisters.
6. Myasthenia gravis: an autoimmune disorder that affects the nervous system, causing muscle weakness and fatigue.
7. Goodpasture's syndrome: a rare autoimmune disease that affects the kidneys and lungs, characterized by the presence of immune complexes in the glomeruli of the kidneys.
8. Hemolytic uremic syndrome (HUS): a condition in which red blood cells are destroyed and waste products accumulate in the kidneys, leading to kidney failure.

Immune complex diseases can be caused by various factors, including genetic predisposition, environmental triggers, and exposure to certain drugs or toxins. Treatment options for these diseases include medications that suppress the immune system, such as corticosteroids and immunosuppressive drugs, and plasmapheresis, which is a process that removes harmful antibodies from the blood. In some cases, organ transplantation may be necessary.

In conclusion, immune complex diseases are a group of disorders that occur when the body's immune system mistakenly attacks its own tissues and organs, leading to inflammation and damage. These diseases can affect various parts of the body, including the skin, kidneys, lungs, and nervous system. Treatment options vary depending on the specific disease and its severity, but may include medications that suppress the immune system and plasmapheresis.

C3a is one of the proteins formed by the cleavage of complement component 3; the other is C3b. C3a is a 77 residue ... C3a molecules induce responses through the GPCR C3a receptor. Like other anaphylatoxins, C3a is regulated by cleavage of its ... C3a has a regulatory process and a structure homologous to complement component C5a, with which it shares 36% of its sequence ... C3a formation occurs through activation and cleavage of complement component 3 in a reaction catalyzed by C3-convertase. There ...

https://en.wikipedia.org/wiki/C3a_(complement)

Complement 3 (C3) through its interaction with factors B and D (adipsin) generates C3a. In the human body, C3a is rapidly ... Complement peptide C5a, C4a, and C3a receptors". Pharmacol. Rev. 65 (1): 500-43. doi:10.1124/pr.111.005223. PMID 23383423. ... The view of C3a/C3adesArg as an acylation stimulating activity is not universally accepted. The evidence is discussed in a ... Thus, most of plasmatic C3a is present in C3adesArg form. C3adesArg is more commonly named ASP or acylation-stimulating-protein ...

https://en.wikipedia.org/wiki/Acylation_stimulating_protein

Complement peptide C5a, C4a, and C3a receptors". Pharmacological Reviews. 65 (1): 500-43. doi:10.1124/pr.111.005223. PMID ... The C5a receptor also known as complement component 5a receptor 1 (C5AR1) or CD88 (Cluster of Differentiation 88) is a G ... Complement component 5a for binding mechanism GRCh38: Ensembl release 89: ENSG00000197405 - Ensembl, May 2017 GRCm38: Ensembl ... Brennan FH, Gordon R, Lao HW, Biggins PJ, Taylor SM, Franklin RJ, Woodruff TM, Ruitenberg MJ (April 2015). "The Complement ...

https://en.wikipedia.org/wiki/C5a_receptor

Complement peptide C5a, C4a, and C3a receptors". Pharmacological Reviews. 65 (1): 500-43. doi:10.1124/pr.111.005223. PMID ... Complement peptide C5a, C4a, and C3a receptors". Pharmacological Reviews. 65 (1): 500-43. doi:10.1124/pr.111.005223. PMID ... Complement+C5a at the US National Library of Medicine Medical Subject Headings (MeSH) (Webarchive template wayback links, ... C5a is a protein fragment released from cleavage of complement component C5 by protease C5-convertase into C5a and C5b ...

https://en.wikipedia.org/wiki/Complement_component_5a

All three pathways converge at a step in which complement protein C3 is cleaved into proteins C3a and C3b, which results in a ... Complement component 4A Complement component 4B HLA A1-B8-DR3-DQ2 haplotype Complement system Complement deficiency Sekar A, ... Complement peptide C5a, C4a, and C3a receptors". Pharmacological Reviews. 65 (1): 500-43. doi:10.1124/pr.111.005223. PMID ... Complement component 4 (C4), in humans, is a protein involved in the intricate complement system, originating from the human ...

https://en.wikipedia.org/wiki/Complement_component_4

Complement peptide C5a, C4a, and C3a receptors". Pharmacological Reviews. 65 (1): 500-43. doi:10.1124/pr.111.005223. PMID ... Polymorphisms of complement component 3, complement factor B, and complement factor I, as well as deletion of complement factor ... The complement system, also known as complement cascade, is a part of the immune system that enhances (complements) the ability ... Three biochemical pathways activate the complement system: the classical complement pathway, the alternative complement pathway ...

https://en.wikipedia.org/wiki/Complement_system

... bacteria-induced complement activation also causes the formation of complement component 3a (C3a) by cleavage from complement ... Complement peptide C5a, C4a, and C3a receptors". Pharmacological Reviews. 65 (1): 500-43. doi:10.1124/pr.111.005223. PMID ... the C3a receptor, whose gene is located at chromosome 12p13; C3a also acts through C5L2. Mouse formyl peptide receptor genes ... Paral D, Sohns B, Crass T, Grove M, Köhl J, Klos A, Bautsch W (Aug 1998). "Genomic organization of the human C3a receptor". ...

https://en.wikipedia.org/wiki/Formyl_peptide_receptor_1

It's a complement component G protein-coupled receptor, of class A (rhodopsin-like). The anaphylatoxins C3a, C4a, and C5a are ... Complement peptide C5a, C4a, and C3a receptors". Pharmacol. Rev. 65 (1): 500-43. doi:10.1124/pr.111.005223. PMID 23383423. Ohno ... "Complement Peptide Receptors: C5a2". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical ... Cain SA, Monk PN (2002). "The orphan receptor C5L2 has high affinity binding sites for complement fragments C5a and C5a des-Arg ...

https://en.wikipedia.org/wiki/C5AR2

... may refer to: C3a (complement) C3a receptor 3 CaO • Al2O3, Tricalcium aluminate in cement chemist notation This ...

https://en.wikipedia.org/wiki/C3a

1996). "Molecular cloning and characterization of the human anaphylatoxin C3a receptor". J. Biol. Chem. 271 (34): 20231-4. doi: ... Complement component 5 is involved in the complement system. It is cleaved into C5a and C5b: C5a plays an important role in ... Complement component 5 is the fifth component of complement, which plays an important role in inflammatory and cell killing ... 2008). "Structure of and influence of a tick complement inhibitor on human complement component 5". Nat Immunol. 9 (7): 753-60 ...

https://en.wikipedia.org/wiki/Complement_component_5

"Complement fragment C3a controls mutual cell attraction during collective cell migration". Developmental Cell. 21 (6): 1026-37 ... C3a in neural crest cells), that stimulates other cells in the group that have the receptors to that chemo-attractant. Cells ...

https://en.wikipedia.org/wiki/Collective_cell_migration

C3a - the other fragment C3 is cleaved into along with C3b Liszewski, M. Kathryn; Atkinson, John P. (2015-06-10). "Complement ... The C1 complement complex binds to these antibodies resulting in its activation via cross proteolysis. This activated C1 ... C3b is the larger of two elements formed by the cleavage of complement component 3, and is considered an important part of the ... In the alternative pathway, C3, present in the blood stream, spontaneously cleaves at low rates into C3b and C3a. If a microbe ...

https://en.wikipedia.org/wiki/C3b

C3a and C5a, proteins produced from the complement system, attract neutrophils to the vessels. Once activated, neutrophils then ... "Complement Activation in Inflammatory Skin Diseases". Frontiers in Immunology. 9: 639. doi:10.3389/fimmu.2018.00639. ISSN 1664- ... immune complexes deposit in vessel walls leading to activation of the complement system. ...

https://en.wikipedia.org/wiki/Cutaneous_small-vessel_vasculitis

Complement 3a (C3a) and complement 5a (C5a) are intermediate products of the complement cascade.[citation needed] Their ... Leukocytes also move toward chemoattractants C5a, a complement component, and pathogen-specific ligands on bacteria. Mechanisms ... "Interactions of the complement system with endotoxic lipopolysaccharide. Generation of a factor chemotactic for ... synthesis is joined to the three alternative pathways (classical, lectin-dependent, and alternative) of complement activation ...

https://en.wikipedia.org/wiki/Chemotaxis

"Europium-Labeled Synthetic C3a Protein as a Novel Fluorescent Probe for Human Complement C3a Receptor" (PDF). Bioconjugate ... β2-adrenergic receptor and C3a receptor. The emitted photons from excited lanthanides are detected by highly sensitive devices ...

https://en.wikipedia.org/wiki/Lanthanide_probes

Isohemagglutinins also activate the complement cascade via C3a and C5a, which then promote inflammatory cytokine release from ...

https://en.wikipedia.org/wiki/Acute_hemolytic_transfusion_reaction

... cleaving most C3 molecules in the serum into C3a and C3b fragments, which depletes the amount of intact C3. C3 deficiency makes ... Complement 3 deficiency is a genetic condition affecting complement component 3 (C3). People can suffer from either primary or ... C3 is the most abundant complement component and is a particularly important complement component because there are three ways ... Complement component 3 (C3) is a protein involved in both the innate and adaptive immune response. C3 is one of over 30 ...

https://en.wikipedia.org/wiki/Complement_3_deficiency

C3a, C5a, IL-8 are all chemotactic factors of the activated complement system. Part of their role is to recruit ... or complement mediated. They then looked at the complement factors and immunoglobulin deposits to identify the underlying cause ... Inactive and active complement proteins that split fragments are found in the glomeruli. There are currently drugs available ... There are no current clinical trials for DPGN happening.[citation needed] Activating complement pathways plays a large role in ...

https://en.wikipedia.org/wiki/Diffuse_proliferative_nephritis

... can cleave multiple C3 proteins into C3a and C3b. The complex is believed to be unstable until it binds properdin, a serum ... cells from complement-mediated damage. CFHR5 (Complement Factor H-Related protein 5) is able to bind to act as a cofactor for ... there are several different kinds of regulatory proteins that disrupt the complement activation process: Complement Receptor 1 ... The alternative pathway is a type of cascade reaction of the complement system and is a component of the innate immune system, ...

https://en.wikipedia.org/wiki/Alternative_complement_pathway

C3a, C4a and C5a) that are produced as part of the activation of the complement system. Complement components C3, C4 and C5 are ... C3a works with C5a to activate mast cells, recruit antibody, complement and phagocytic cells and increase fluid in the tissue, ... coded for by a single exon within the complement protein gene. The C3a, C4a and C5a components are referred to as ... This term is reserved only for fragments of the complement system. C3, C4A, C4B, C4B-1, C5, FBLN1, FBLN2 Allergy Anaphylatoxin ...

https://en.wikipedia.org/wiki/Anaphylatoxin

The formation of complement proteins (C3a, C3b, C5a, C5b, etc.) ultimately congregates into a membrane-attack complex to lyse ... followed by the cleavage of C3 protein into C3a and C3b protein. C3a protein serves as an inflammation mediator to recruit ... Antibodies can also trigger the classical pathway - one of the three pathways of the complement cascade. Briefly, the C1 ... In addition to the generation of complement proteins, C1 complex also induces the activation of B cells, monocytes, macrophages ...

https://en.wikipedia.org/wiki/Passive_antibody_therapy

His work also confirmed that an anaphylatoxin molecule of complement activation "C3a" enhances intestinal stem cell expansion, ... Tsokos established the role of complement activation in tissue injury and regeneration. His findings demonstrated for the first ... "Complement deposition on the surface of RBC after trauma serves a biomarker of moderate trauma severity: A prospective study". ... "C3a Enhances the Formation of Intestinal Organoids through C3aR1". Frontiers in Immunology. 8: 1046. doi:10.3389/fimmu. ...

https://en.wikipedia.org/wiki/George_Tsokos

"Characterization of synthetic C3a analog peptides on human eosinophils in comparison to the native complement component C3a". ... is a G protein-coupled receptor protein involved in the complement system. The receptor binds to complement component C3a, ... Complement peptide C5a, C4a, and C3a receptors". Pharmacological Reviews. 65 (1): 500-43. doi:10.1124/pr.111.005223. PMID ... The C3a receptor also known as complement component 3a receptor 1 (C3AR1) ...

https://en.wikipedia.org/wiki/C3a_receptor

Cleavage of complement C3 by a free floating convertase, thrombin, plasmin or even a bacterial enzyme leads to formation of C3a ... DAF protects host cells from damage by autologous complement. DAF acts on C2b and Bb and dissociates them rapidly from C4b and ... Hourcade D (2006). "The Role of Properdin in the Assembly of the Alternative Pathway C3 Convertases of Complement". J Biol Chem ... C3+convertase at the US National Library of Medicine Medical Subject Headings (MeSH) Portal: Biology (Complement system, EC 3.4 ...

https://en.wikipedia.org/wiki/C3-convertase

September 2009). "Complement protease MASP-1 activates human endothelial cells: PAR4 activation is a link between complement ... C2a and C4b are used to create C3 convertase, a complex that will then be able to cleave C3 into C3a and C3b. However, MASP-1 ... MASP-1 is a serine protease that functions as a component of the lectin pathway of complement activation. The complement ... "The role of MASP-1/3 in complement activation". In Lambris JD, Holers VM, Ricklin D (eds.). Complement Therapeutics. Advances ...

https://en.wikipedia.org/wiki/MASP1_(protein)

... complement components C5a and C3a which are chemotactic factors formed during the activation of the host's blood complement ...

https://en.wikipedia.org/wiki/Specialized_pro-resolving_mediators

While the anaphylatoxin C3a interacts with its C3a receptor (C3aR) to recruit leukocytes, C3b contributes to further downstream ... Alternative complement pathway - another complement system pathway Lectin pathway - another complement system pathway Noris, ... The classical complement pathway is one of three pathways which activate the complement system, which is part of the immune ... Activation of the complement pathway through the classical, lectin or alternative complement pathway is followed by a cascade ...

https://en.wikipedia.org/wiki/Classical_complement_pathway

... complement components C3a and C5a, split tyrosyl tRNA synthetase (mini TyrRS), dimerized ribosomal protein S19 (RP S19), ...

https://en.wikipedia.org/wiki/Find-me_signals

... s have a variety of specific receptors, including ones for complement, cytokines like interleukins and IFN-γ, ... C3a, C5a, and Leukotriene B4, which these cells use to direct the path of their migration. ...

https://en.wikipedia.org/wiki/Neutrophil

... complement c3 MeSH D12.776.124.486.274.250.250 - complement c3a MeSH D12.776.124.486.274.250.260 - complement c3b MeSH D12.776. ... complement c3a MeSH D12.776.124.486.274.024.260 - complement c4a MeSH D12.776.124.486.274.024.270 - complement c5a MeSH D12.776 ... complement c1 MeSH D12.776.124.486.274.050.270 - complement c1q MeSH D12.776.124.486.274.050.280 - complement c1r MeSH D12.776. ... complement c2 MeSH D12.776.124.486.274.150.500 - complement c2a MeSH D12.776.124.486.274.150.750 - complement c2b MeSH D12.776. ...

https://en.wikipedia.org/wiki/List_of_MeSH_codes_(D12.776.124)

C3a is an anaphylotoxin and the precursor of some cytokines such as ASP, and C3b serves as an opsonizing agent. Factor I can ... Complement component 3, often simply called C3, is a protein of the immune system. It plays a central role in the complement ... "Entrez Gene: C3 complement component 3". Sahu A, Lambris JD (Apr 2001). "Structure and biology of complement protein C3, a ... In the alternative complement pathway, C3 is cleaved by C3bBb, another form of C3-convertase composed of activated forms of C3 ...

https://en.wikipedia.org/wiki/Complement_component_3

The structure of an AT module was determined for the complement-derived anaphylatoxin C3a, and was found to be a compact alpha- ...

https://en.wikipedia.org/wiki/Fibulin

Antibodies are produced against the RBCs, which leads to complement activation. Complement fragments, such as C3a, C4a and C5a ... Cases may also arise with complement alone or with IgA, IgM or a combination of these three antibody classes and complement. ... IgM is a potent activator of the classical complement pathway, thus, AIHA involving IgM is characterized by complement-mediated ... When these RBCs return to central regions, they are damaged by complement. Patients may present with one or both types of ...

https://en.wikipedia.org/wiki/Autoimmune_hemolytic_anemia

... histamine-inducers Complement proteins C3a, C4a, and C5a work by triggering histamine release from mast cells and basophil ...

https://en.wikipedia.org/wiki/Vasodilation

Plasma derived complement C3b and antibodies that exude into the inflamed tissue during the vascular phase bind to and coat the ... A variety of molecules behave as chemoattractants, for example, C3a or C5, and cause the leukocytes to move along a chemotactic ... These include the complement system activated by bacteria and the coagulation and fibrinolysis systems activated by necrosis (e ... The complement system, when activated, creates a cascade of chemical reactions that promotes opsonization, chemotaxis, and ...

https://en.wikipedia.org/wiki/Inflammation

The cause of damage is as a result of the action of cleaved complement anaphylotoxins C3a and C5a, which, respectively, mediate ... are far more capable of interacting with complement; these medium-sized complexes, formed in the slight excess of antigen, are ... leading to small immune complexes being formed that fix complement and are not cleared from the circulation. It involves ...

https://en.wikipedia.org/wiki/Type_III_hypersensitivity

The aureolysin derived C3a and C3b are further degraded by host complement inhibitor factor H and I. In the lectin pathway, ... Of all the proteases, aureolysin is the most effective against the complement cascade. In all three pathways of complement ... The active site has a high affinity for C3 and will cleave it into C3a and C3b however, the protein is cleaved two amino acid ... Further immune evasion outside of the complement system occurs in various ways. Aureolysin cleaves and inactivates protease ...

https://en.wikipedia.org/wiki/Aureolysin

At the same time, they suggest a minimal role for C3a, since neutropenia rather than C3a receptor antagonism appears to be ... Role of the complement components C5 and C3a in a mouse model of myocardial ischemia and reperfusion injury Marc N Busche 1 , ... Role of the complement components C5 and C3a in a mouse model of myocardial ischemia and reperfusion injury Marc N Busche et al ... Keywords: C3a; C5; I/R; cardiac; complement; heart; ischemia; ischemic heart disease; myocardial; reperfusion. ...

https://pubmed.ncbi.nlm.nih.gov/20930931

Pancreatic adenocarcinoma; complement C3a; complement C3a receptor; epithelial-to-mesenchymal transition; metastasis ... The Complement C3a-C3a Receptor Axis Regulates Epithelial-to-Mesenchymal Transition by Activating the ERK Pathway in Pancreatic ... The Complement C3a-C3a Receptor Axis Regulates Epithelial-to-Mesenchymal Transition by Act ... We aimed to clarify the role of complement C3a and its receptor C3aR in progression of pancreatic ductal adenocarcinoma (PDAC ...

https://pesquisa.bvsalud.org/controlecancer/resource/pt/mdl-35220210

Complement effectors such as C1q, anaphylatoxins C3a and C5a, and their receptors C3aR and C5aR1, have been associated with ... Keywords: C1q; C3a; C5a; PD-1; PD-L1; cancer immunity; complement system; immunotherapy. ... This review focuses on the elements of the complement system that come into play in the cancer-immunity cycle. The complement ... Complementing the Cancer-Immunity Cycle Front Immunol. 2019 Apr 12;10:774. doi: 10.3389/fimmu.2019.00774. eCollection 2019. ...

https://pubmed.ncbi.nlm.nih.gov/31031765/

The C3 gene provides instructions for making a protein called complement component 3 (or C3). Learn about this gene and related ... This protein plays a key role in a part of the bodys immune response known as the complement system. The complement system is ... One of these pieces, called C3b, interacts with several other proteins on the surface of cells to trigger the complement ... The C3 protein is essential for turning on (activating) the complement system. The presence of foreign invaders triggers the C3 ...

https://medlineplus.gov/genetics/gene/c3/

Complement C3a des Arg (1). * Corticosterone (1). * Cotinine (1). * DDDDK tag (Binds to FLAG® tag sequence) (1). ...

https://www.abcam.com/products?sortOptions=Relevance&selected.classification=ELISA+and+Matched+Antibody+Pair+Kits&selected.assayType=Competitive

Equid herpesvirus 3 strain AR/2007/C3A, complete genome Equid herpesvirus 3 strain AR/2007/C3A, complete genome. gi,675510705, ... Equid herpesvirus 3 strain AR/2007/C3A, complete genome. NCBI Reference Sequence: NC_024771.1 ...

https://www.ncbi.nlm.nih.gov/nuccore/675510705

C3, complement C3. * Synonyms AHUS5, ARMD9, ASP, C3a, C3b, CPAMD1, HEL-S-62p ... J:5960 Da Silva FP, et al., Murine complement component 3: genetic variation and linkage to H-2. Proc Natl Acad Sci U S A. 1978 ... Human Disease Modeled: complement component 3 deficiency. Allelic Composition. Genetic Background. Reference. Phenotypes. ... Helicobacter pylori initiates successful gastric colonization by utilizing L-lactate to promote complement resistance. Nat ...

https://www.informatics.jax.org/marker/MGI:88227

The Complement C3a. Ren W; Liu Y; Wang X; Piao C; Ma Y; Qiu S; Jia L; Chen B; Wang Y; Jiang W; Zheng S; Liu C; Dai N; Lan F; ...

https://pubmedhh.nlm.nih.gov/biomarkers/search.php?id=35100526&mod=related&page=1&outid=&proj=

Complement C3a/metabolism*; Granulocyte-Macrophage Colony-Stimulating Factor/metabolism; Hypersensitivity/immunology*; Immunity ... C3 and C3a have been shown to be important for the development of Th2 responses, yet remarkably, the mechanisms by which C3a ... Our data suggests that ILC2 recruitment is C3a-dependent. Further, we show that ILC2s directly respond to C3a, promoting type 2 ... Title: C3a is required for ILC2 function in allergic airway inflammation.. Authors: Gour, Naina; Smole, Ursula; Yong, Hwan-Mee ...

https://tools.niehs.nih.gov/portfolio/index.cfm?do=portfolio.publicationDetail&id=3467500

Another immunologic mechanism for mast cell degranulation is mediated by complement-derived anaphylatoxins C3a, C4a and C5a. ...

https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=4e6f2764-63a7-4d99-82c6-3b319a246296&audience=consumer

What were we missing? And it didnt take too long before complement with C3a and C4a came along. Every year. VEGF would be one ... They will initiate additional cascades, C3a, C4a coming out within 4 to 24 hours, TGF-beta1 coming out within 16 to 24 hours. ... Ritchie Shoemaker, MD: And what illness has complement involved and proinflammatory cytokines and antiinflammatory cytokines ... and genetic susceptibility and TGF-beta1 and then complement? What has all of those at the same time? Well, our good friend ...

https://chriskresser.com/dr-ritchie-shoemaker-on-chronic-inflammatory-response-syndrome/comment-page-2/

Many pathogen-associated molecular patterns activate both TLR and complement, but whether and how these 2 systems, when ... and complement are 2 components of innate immunity that are critical for first-line host defense and elicitation of adaptive ... Complement protein C3a enhances adaptive immune responses towards FVIII products. Ringler E, Iannazzo SO, Herzig J, Weiss LM, ... In the absence of the complement regulatory protein DAF, complement activation and its effect on TLR signaling is amplified. ...

https://pubmed.ncbi.nlm.nih.gov/17363730

Isoantibodies trigger and fix the complement system to surfaces of RBCs. C3a and C5a activate white blood cells to release ... IgM antibodies to group A and B antigens fix complement and cause rapid hemolysis. ...

https://www.unboundmedicine.com/5minute/view/5-Minute-Clinical-Consult/1688705/all/Transfusion_Reaction__Hemolytic

Conversion of C3PA to C3A and hemolytic consumption were dose dependent. The chelation tests indicated that complement ... C3A) was measured, along with total hemolytic activity of complement. Some NHS samples were treated with chelating agents prior ... The dusts also were tested with guinea pig serum that was deficient in the fourth component of complement (C4D). The dust and ... The dusts and extract were added to normal human serum (NHS). The rate of conversion of the third component of complement (C3PA ...

http://www2a.cdc.gov/nioshtic-2/BuildQyr.asp?s1=agricultur%2A+or+farm%2A&f1=%2A&Adv=0&terms=1&PageNo=662&RecNo=6617&View=f&

Complement Component 3. *Complement Component C3a. *Complement Component C3b. *Epididymis Secretory Sperm Binding Protein Li ... From NCBI Gene: Complement component C3 plays a central role in the activation of complement system. Its activation is required ... The C3a peptide, also known as the C3a anaphylatoxin, modulates inflammation and possesses antimicrobial activity. Mutations in ... for both classical and alternative complement activation pathways. The encoded preproprotein is proteolytically processed to ...

https://edrn.nci.nih.gov/data-and-resources/biomarkers/c3/

COMPLEMENT C5A; and COMPLEMENT C5A, DES-ARGININE.. Entry Term(s). C3a Complement Complement 3a Complement Component 3a Pharm ... Complement C3 [D12.776.124.486.274.250] * Complement C3a [D12.776.124.486.274.250.250] * Complement C3b [D12.776.124.486. ... C3a is considered an anaphylatoxin along with COMPLEMENT C4A; COMPLEMENT C5A; and COMPLEMENT C5A, DES-ARGININE.. Terms. ... Complement C3a. Previous Indexing. Anaphylatoxins (1977-1989). Complement (1967-1976). Complement 3 (1975-1989). Public MeSH ...

https://meshb.nlm.nih.gov/record/ui?ui=D015926

In order to ascertain the role that complement plays in resolving VEEV-induced disease, complement-deficient C3−/− mice were ... In the absence of a functional complement system, peripheral inoculation with V3533 induced much more severe encephalitis. This ... These findings indicate that complement-dependent enhancement of peripheral virus clearance is critical for protecting against ... Norgauer J., Dobos G., Kownatzki E., Dahinden C., Burger R., Kupper R., Gierschik P. 1993; Complement fragment C3a stimulates ...

https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.038281-0

The complement C3a receptor contributes to melanoma tumorigenesis by inhibiting neutrophil and CD4+ T cell responses ... These data indicate that complement activation, or the presence of elements of the complement pathway, may inhibit the efficacy ... In support of these observations, a study established that T cells express C3a and C5a receptors that interact with the IL10 ... It would also be important to observe changes in the levels of complement and wound healing activation at baseline and over ...

https://aacrjournals.org/cancerimmunolres/article/6/1/79/468811/A-Serum-Protein-Signature-Associated-with-Outcome

Degranulation can be triggered by cross-linking of IgE receptors or by the anaphylatoxin complement fragments C3a and C5a. ... G and for complement, which enable them to bind with immune complexes and present the complex to B cells in germinal centers of ... as receptors for components of the complement system, and others. (For further information on CD molecules, see the Human Cell ...

https://www.merckmanuals.com/en-ca/professional/immunology-allergic-disorders/biology-of-the-immune-system/cellular-components-of-the-immune-system

Complement your expertise with ours to improve test selection and interpretation.. Learn more ...

https://www.questdiagnostics.com/locations/detail.html/C3A/80112/75/1

Complement C3a; ASP, Complement C3 DesArg, Acetylation-stimulating Protein ASP, Complement C3 DesArg, Acetylation-stimulating ... Complement C3a; ASP, Complement C3 DesArg, Acetylation-stimulating Protein ASP, Complement C3 DesArg, Acetylation-stimulating ... Complement CH50; Total Hemolytic Complement; CH50 CH50; Complement CH50; Total Hemolytic Complement 3/28/2014 n/a I C74851 ... Complement CH50; Total Hemolytic Complement; CH50 CH50; Complement CH50; Total Hemolytic Complement 3/28/2014 n/a I C74851 ...

https://evs.nci.nih.gov/ftp1/CDISC/SDTM/Archive/SDTM%20Terminology%20Changes%202014-03-28.txt

Complement activation during cardiopulmonary bypass: evidence for generation of C3a and C5a anaphylatoxins. N Engl J Med 1981; ... complement system activation with measurements of complement (C)1q, C5a, C9, C3, C4, complement factor B, complement factor H, ... Complement (C)1q, Complement Factor B, Complement Factor H, C5a, C9, and Mannose-Binding Lectin (classic and alternate ... Complement system activation. *Child neurodevelopment, function, and quality of life at 6 and 12 months, as measured by:*Ages ...

https://researchprotocols.org/2023/1/e43760

Some important proteins migrate into this fraction such as complement, C-reactive protein (CRP), and transferrin, as well as ... resulting in increased synthesis of chemotactic peptides C3a and C5a, which mobilize eosinophils to the site of infection [46, ... β-globulin fraction after antiparasitic treatment may reflect the increase of some components of the complement system, ... ferritin [22]. The activation of the complement pathway is one of the first nonspecific innate defense responses to the ...

https://www.hindawi.com/journals/vmi/2021/9946519/

complement C3a receptor 1 [Source:HGNC.... CCDC106. 29903. CCDC106. coiled-coil domain containing 106 [Sou.... ...

https://www.gsea-msigdb.org/gsea/msigdb/human/geneset/GSE9006_HEALTHY_VS_TYPE_1_DIABETES_PBMC_AT_DX_DN.html

The complement system contributes to autoimmune injury, but its involvement in promoting the development of autoimmune diabetes ... Locally produced complement fragments C5a and C3a provide both costimulatory and survival signals to naive CD4+ T cells ... This gap in the understanding of the function of complement in type 1 diabetes is unexpected, given that complement effectors, ... yielding C3a and C5a that bind to C3a/C5a receptors (C3aR/C5aR) on both partners (5). The resultant G-protein-coupled receptor ...

https://diabetesjournals.org/diabetes/article/59/9/2247/14250/Immune-Cell-Derived-C3-Is-Required-for-Autoimmune

... complement- activation generated anaphylatoxins assays (C3a, C4a and C5a); and 5) contact system (kinin/kallikrein) activation ...

https://researchfestival.nih.gov/2015/posters/developing-vitro-and-vivo-models-predict-drug-induced-acute-allergic

Whole polyclonal antiserum from rabbits immunized with highly purified human complement protein. ... Whole polyclonal antiserum from rabbits immunized with highly purified human complement protein. ...

https://www.tecomedical.com/de/Diagnostik-Assays-Reagenzien/Komplement-/Komplement-Polyklonales-Antiserum/C3a-Human-Polyclonal-Rabbit-Antiserum/

The complement system is an evolutionarily ancient key component of innate immunity required for the detection and removal of ... Direct effects of complement receptor activation on antigen presenting cells. On APCs (DCs), signaling of C5a and C3a through ... In particular, work on the impact of complement on T cell responses led to the surprising discoveries that the complement ... Complement and the Regulation of T Cell Responses Erin E West 1 , Martin Kolev 2 , Claudia Kemper 1 2 3 ...

https://www.ncbi.nlm.nih.gov/pubmed/29677470

Certain byproducts of the cascade-plasma-activated complement 3 (C3a), plasma-activated complement 4 (C4a), and plasma- ... to complement activation. Immune complexes formed in vivo or in vitro can activate the complement cascade. ... These mediators can activate the kallikrein-kinin contact system, the complement cascade, and coagulation pathways. The ... Evidence also exists that dextrans and protamine can activate several inflammatory pathways, including complement, coagulation ...

http://emedicine.medscape.com/article/135065-overview

Complement effectors such as C1q, anaphylatoxins C3a and C5a, and their receptors C3aR and C5aR1, have been associated with tolerogenic cell death and inhibition of antitumor T-cell responses through the recruitment and/or activation of immunosuppressive cell subpopulations such as myeloid-derived suppressor cells (MDSCs), regulatory T cells (Tregs), or M2 tumor-associated macrophages (TAMs). (nih.gov)
Another immunologic mechanism for mast cell degranulation is mediated by complement-derived anaphylatoxins C3a, C4a and C5a. (nih.gov)
Description: The complement component proteins, C2, C3, C4 and C5, are potent anaphylatoxins that are released during complement activation. (wlsolutions.be)
2017 Immunity) links non-canonical activation of complement (specifically C5a and C3a - complement anaphylatoxins) to AMD initiation. (nih.gov)

Systemic C5 or C3a inhibition was performed with an anti-C5 monoclonal antibody (BB5.1) 30 min prior to reperfusion or with a C3a receptor antagonist (C3aRA). (nih.gov)
The Complement C3a-C3a Receptor Axis Regulates Epithelial-to-Mesenchymal Transition by Activating the ERK Pathway in Pancreatic Ductal Adenocarcinoma. (bvsalud.org)
We aimed to clarify the role of complement C3a and its receptor C3aR in progression of pancreatic ductal adenocarcinoma (PDAC). (bvsalud.org)
complement C3a receptor 1 [Source:HGNC. (gsea-msigdb.org)
C3d is a terminal degradation product of C3 that plays an important role in modulation of the adaptive immune response through the interaction with complement receptor type 2 (CR2). (wlsolutions.be)
VGF-derived peptide TLQP-21 activates the complement C3a receptor-1 (C3aR1), predominantly expressed in the brain on microglia. (nih.gov)
C3a receptor 1 Knockout (C3aR1 KO) mice on a C57BL/6 J background were also used in this study. (nih.gov)

In susceptible individuals, allergen exposure triggers the activation of complement, a major arm of innate immunity, leading to the aberrant generation of the C3a anaphylatoxin. (nih.gov)
The regulatory effect of complement on TLR-induced cytokine production in vivo was mediated by the anaphylatoxin receptors C5aR and C3aR. (nih.gov)
The C3a peptide, also known as the C3a anaphylatoxin, modulates inflammation and possesses antimicrobial activity. (nih.gov)

C3a, a 77-amino acid peptide, is a mediator of local inflammatory process. (nih.gov)

The C3 gene provides instructions for making a protein called complement component 3 (or C3). (medlineplus.gov)
From NCBI Gene: Complement component C3 plays a central role in the activation of complement system. (nih.gov)
The rate of conversion of the third component of complement (C3PA) to its activator form (C3A) was measured, along with total hemolytic activity of complement. (cdc.gov)
The dusts also were tested with guinea pig serum that was deficient in the fourth component of complement (C4D). (cdc.gov)
Coincident with the induced elevations in blood glucose levels, we documented alternative pathway complement component gene expression within the islets of the diabetic WT mice. (diabetesjournals.org)
The complement system is an evolutionarily ancient key component of innate immunity required for the detection and removal of invading pathogens. (nih.gov)

We performed phagocytic/migration assays and RNA sequencing on BV2 microglial cells and primary microglia isolated from wild-type or C3aR1-null mice following treatment with TLQP-21 or C3a super agonist (C3aSA). (nih.gov)

IgM antibodies to group A and B antigens fix complement and cause rapid hemolysis. (unboundmedicine.com)
Type II hypersensitivity is characterized by Ig-M and Ig-G antibodies that bind to cell surface antigens inducing activation of complement cascades and phagocytosis. (bdbiosciences.com)
These antibodies - as well as other substances called complement - serve as biomarkers for lupus and are indicators of many immune system problems that lead to clinical manifestations of the disease. (nih.gov)
Blood tests measuring lupus biomarkers - including anti-ds (double-stranded) DNA antibodies and complement C3a - were performed at monthly intervals. (nih.gov)

This protein plays a key role in a part of the body's immune response known as the complement system. (medlineplus.gov)
The C3 protein is essential for turning on (activating) the complement system. (medlineplus.gov)
This genetic change is described as a "gain-of-function" mutation because it leads to an altered version of the protein that overactivates the complement system. (medlineplus.gov)
These mutations are described as "loss-of-function" because the abnormal or missing C3 protein prevents normal activation of the complement system. (medlineplus.gov)
Whole polyclonal antiserum from rabbits immunized with highly purified human complement protein. (tecomedical.com)

In order to ascertain the role that complement plays in resolving VEEV-induced disease, complement-deficient C3 −/− mice were infected with a VEEV mutant (V3533) that caused mild, transient disease in immunocompetent mice. (microbiologyresearch.org)
In this study, our goal was to ascertain the role of complement C3 in autoimmune diabetes. (diabetesjournals.org)

The complement system, an essential part of innate immunity, has emerged as a major regulator of cancer immunity. (nih.gov)
We demonstrate a central role for C3a in driving type 2 innate lymphoid cells (ILC2)-mediated inflammation in response to allergen and IL-33. (nih.gov)
In summary, we identify a novel mechanism by which C3a can mediate aberrant type 2 responses to aeroallergen exposure, which involves a yet unrecognized cross-talk between two major innate immune components-complement and group 2 innate lymphoid cells. (nih.gov)
Toll-like receptors (TLRs) and complement are 2 components of innate immunity that are critical for first-line host defense and elicitation of adaptive immune responses. (nih.gov)

The complement system in regulation of adaptive immunity. (microbiologyresearch.org)
More recently, complement has also emerged as a critical player in adaptive immunity via its ability to instruct both B and T cell responses. (nih.gov)

In previous work, we showed that during cognate T cell/APC interactions, immune cell-derived complement activates locally, yielding C3a and C5a that bind to C3a/C5a receptors (C3aR/C5aR) on both partners ( 5 ). (diabetesjournals.org)

B lymphocyte memory: role of stromal cell complement and FcγRIIB receptors. (microbiologyresearch.org)
they have receptors for the crystallizable fragment (Fc) region of immunoglobulin (Ig) G and for complement, which enable them to bind with immune complexes and present the complex to B cells in germinal centers of secondary lymphoid organs. (merckmanuals.com)
Recently, in vitro activation of non-canonical complement in RPE cultures has been linked to changes in RPE structure, increased "drusen" formation, reduced autophagy, increased activation of inflammasome and inflammatory cytokines, and increased activation of NFƙb signaling pathway (through CD88 and TLR4 receptors) (Pilgrim et al. (nih.gov)

Purified antigens might have contaminants, or might not contain the full complement of native proteins. (bmj.com)

To confirm the protumoral effects of C3a in PDAC, we conducted in vitro experiments using PDAC cell lines (Panc-1 and MiaPaca-2) that exhibit high C3aR expression. (bvsalud.org)
Inhibition of the C3a-C3aR axis by pharmacological blockade and short-hairpin RNA -mediated knockdown of C3aR alleviated its protumoral effect. (bvsalud.org)
These findings provide a new approach for the development of treatments targeting the C3a-C3aR axis. (bvsalud.org)

The smaller fragment generated from the cleavage of complement C3 by C3 CONVERTASE . (nih.gov)

Its activation is required for both classical and alternative complement activation pathways. (nih.gov)
The chelation tests indicated that complement activation occurred via the alternative pathway, rather than via the classical complement pathway. (cdc.gov)
The authors suggest that activation of the alternative complement pathway by grain dusts may be a factor in the respiratory response of exposed workers. (cdc.gov)
These kits allow for the analysis of activation of key proteins and specific pathways of the complement system in serum, plasma, and other biological fluids. (immunoconceptindia.co)

Our complement portfolio consists of several proteases that regulate the complement cascade including CB 2782-PEG, a C3 degrader for the potential treatment of dry AMD, improved CFI protease CB 4332 for patients with deficiencies in CFI including dry AMD, and proteases from our ProTUNE™ C3b/C4b degrader and ImmunoTUNE™ C3a/C5a degrader platforms designed to target other disorders of the complement or inflammatory pathways. (yahoo.com)

Systemic C5 inhibition in clinical studies has resulted in mixed results and the role of earlier complement components (e.g. (nih.gov)

We evaluated the serum levels of C3 and C3a in patients with PDAC. (bvsalud.org)
Serum levels of both C3 and C3a were higher in 26 patients with PDAC than in 28 nontumor-bearing controls. (bvsalud.org)
An Alternative Complement Pathway, Rat, Assay ELISA Kit is a type of assay kit that can measure the activity of the alternative complement pathway in rat serum or plasma samples. (immunoconceptindia.co)
A Classical Complement Pathway, Mouse, Assay ELISA Kit is a type of ELISA kit that can measure the activity of the classical complement pathway in mouse serum or plasma samples. (immunoconceptindia.co)

C3a and C5a activate white blood cells to release inflammatory cytokines such as IL-1, IL-6, IL-8, and TNF- α . (unboundmedicine.com)

A similar outcome was observed in wild-type mice cotreated with the TLR ligands and cobra venom factor, a potent complement activator. (nih.gov)

C3 and C3a have been shown to be important for the development of Th2 responses, yet remarkably, the mechanisms by which C3a regulates type 2 immunity are relatively unknown. (nih.gov)

In vitro experiments showed that C3a facilitated tumor cell proliferation , migration and invasion by activating the extracellular-regulated kinase signaling pathway and inducing epithelial-to-mesenchymal transition. (bvsalud.org)
The TLR ligands lipopolysacharride (TLR4), zymosan (TLR2/6), and CpG oligonucleotide (TLR9) caused, in a complement-dependent manner, strikingly elevated plasma interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-alpha), and IL-1beta, and/or decreased plasma IL-12 levels in mice deficient in the membrane complement inhibitor decay-accelerating factor (DAF). (nih.gov)

We demonstrate here a widespread regulation of TLR signaling by complement in vivo. (nih.gov)

C3a), upstream from C5 cleavage, has not been elucidated for MI/R injury. (nih.gov)

A C3a Plus ELISA Kit is a type of ELISA kit that can measure the amount of C3a (or C3a-desArg) present in various samples. (immunoconceptindia.co)

The complement system plays a major role in inflammation and tissue injury following myocardial ischemia and reperfusion (MI/R) injury. (nih.gov)
The complement system is a group of proteins that work together to destroy foreign invaders (such as bacteria and viruses), trigger inflammation, and remove debris from cells and tissues. (medlineplus.gov)
C3a is required for ILC2 function in allergic airway inflammation. (nih.gov)
The complement system is also activated, and chemo-attracted neutrophils cause local inflammation and tissue damage. (bdbiosciences.com)

This review focuses on the elements of the complement system that come into play in the cancer-immunity cycle. (nih.gov)
This process must be carefully regulated so the complement system targets only unwanted materials and does not damage the body's healthy cells. (medlineplus.gov)
Isoantibodies trigger and fix the complement system to surfaces of RBCs. (unboundmedicine.com)
In the absence of a functional complement system, peripheral inoculation with V3533 induced much more severe encephalitis. (microbiologyresearch.org)
The complement system contributes to autoimmune injury, but its involvement in promoting the development of autoimmune diabetes is unknown. (diabetesjournals.org)
In particular, work on the impact of complement on T cell responses led to the surprising discoveries that the complement system also functions within cells and is involved in regulating basic cellular processes, predominantly those of metabolic nature. (nih.gov)
Special Complements Research Reagents are products that are used for the analysis of the complement system, a part of the immune system that consists of a series of proteins that can be activated by various stimuli. (immunoconceptindia.co)

Therefore, we evaluated the role of C5 or C3a in a mouse model of MI/R injury. (nih.gov)
The data reveal a key role for immune cell-derived C3 in the pathogenesis of murine multiple low-dose streptozotocin-induced diabetes and support the concept that immune cell mediated diabetes is in part complement-dependent. (diabetesjournals.org)

Received Rare Pediatric Disease Designation for CB 4332, an enhanced Complement Factor I ("CFI") for the treatment of CFI Deficiency. (yahoo.com)

Complement cascade leads to rapid intravascular destruction of transfused cells. (unboundmedicine.com)

A subset of 41 patients who remained clinically stable but experienced increases in anti-dsDNA and C3a levels were then randomly assigned to receive prednisone or a placebo. (nih.gov)
The authors concluded that short-term corticosteroid therapy may prevent flares in clinically stable lupus patients with elevated levels of C3a and anti-dsDNA. (nih.gov)

These findings indicate that complement-dependent enhancement of peripheral virus clearance is critical for protecting against the development of severe VEEV-induced encephalitis. (microbiologyresearch.org)
In an editorial accompanying the article, Matthew Liang, M.D., M.P.H. of Brigham and Women's Hospital in Boston, estimates that C3a and anti-dsDNA were predictive of severe flares 40 percent of the time. (nih.gov)

The company's complement portfolio now consists of several wholly-owned drug candidates at various stages of discovery for dry AMD. (yahoo.com)

One of these pieces, called C3b, interacts with several other proteins on the surface of cells to trigger the complement system's response. (medlineplus.gov)

Our data suggests that ILC2 recruitment is C3a-dependent. (nih.gov)

Anatomy15

Organisms10

Diseases16

Chemicals and Drugs101

Analytical, Diagnostic and Therapeutic Techniques and Equipment25

Phenomena and Processes48

Disciplines and Occupations2

Information Science3

Health Care1

Chimeric receptors of the human C3a receptor and C5a receptor (CD88). (1/332)

Regional specificity of ASP binding in human adipose tissue. (2/332)

Effect of permeability on indices of haemodialysis membrane biocompatibility. (3/332)

Modulation of C3a activity: internalization of the human C3a receptor and its inhibition by C5a. (4/332)

Mechanisms involved in the regulation of free fatty acid release from isolated human fat cells by acylation-stimulating protein and insulin. (5/332)

Genetic deficiency of acylation stimulating protein (ASP(C3ades-Arg)) does not cause hyperapobetalipoproteinemia in mice. (6/332)

Role of C3 cleavage in monocyte activation during extracorporeal circulation. (7/332)

Possible mechanism for in vitro complement activation in blood and plasma samples: futhan/EDTA controls in vitro complement activation. (8/332)

Complement C3

Complement C4

Complement C4a

Complement C3a

Complement C1q

Complement C5a

Complement Activation

Complement C4b

Complement C5

Complement C3b

Complement System Proteins

Complement C6

Complement C3c

Complement C3d

Complement C2

Complement C9

Receptors, Complement

Complement C1s

Complement Membrane Attack Complex

Complement C1r

Complement Inactivator Proteins

Complement C7

Complement C3-C5 Convertases

Complement Factor B

Complement Pathway, Alternative

Complement Pathway, Classical

Complement C8

Complement C1

Receptors, Complement 3b

Complement Factor H

Complement C5b

Complement C2a

Receptor, Anaphylatoxin C5a

Complement Activating Enzymes

Complement Inactivating Agents

Complement Hemolytic Activity Assay

Complement C1 Inactivator Proteins

Receptors, Complement 3d

Anaphylatoxins

Complement Fixation Tests

Complement Factor D

Complement Factor I

Complement C4b-Binding Protein

Complement C3b Inactivator Proteins

Antigens, CD55

Complement C3-C5 Convertases, Classical Pathway

Complement C2b

Antigens, CD59

Cobra Venoms

Antigen-Antibody Complex

Steroid 21-Hydroxylase

Complement C3-C5 Convertases, Alternative Pathway

Complement C1 Inhibitor Protein

Immunoglobulin G

Hemolysis

Complement C3 Convertase, Alternative Pathway

Complement C5 Convertase, Classical Pathway

Molecular Sequence Data

Complement C3 Convertase, Classical Pathway

Antigens, CD46

Opsonin Proteins

Blood Proteins

Lupus Erythematosus, Systemic

Complement C5 Convertase, Alternative Pathway

Phagocytosis

Amino Acid Sequence

Complement Pathway, Mannose-Binding Lectin

Properdin

Complement C5a, des-Arginine

Mice, Inbred C57BL

Macrophage-1 Antigen

Protein Binding

Neutrophils

Base Sequence

Kidney Glomerulus

Serum

Glomerulonephritis, Membranoproliferative

Immunoglobulin M

Schistosoma

Genetic Complementation Test