• Bronchoalveolar lavage (BAL) toxicity parameters such as lactate dehydrogenase activity, number of AMs and PMNs, oxidant production by phagocytes, and levels of multiple cytokines (IL-1beta, IL-10, MCP-1, MIP-2, and TNF-alpha) were significantly altered in response to inhalation exposure to MWCNT in the rats. (cdc.gov)
  • Viruses then travel to the alveoli and infect type 2 pneumocytes which, in the youthful system (lower left), are recognized by alveolar macrophages (AMs) or dendritic cells (not pictured) that release cytokines and present antigens to T cells and other adaptive immune cells. (aging-us.com)
  • Through the release of several cytokines, i.e., growth-promoting and inhibiting factors, lung macrophages may also influence both matrix damage and repair processes. (psu.edu)
  • As the resident phagocyte of the lower respiratory tract, the macrophage is a versatile cell with paradoxical effects, able to release oxidants, proteolytic enzymes, and mediators, but also able to secrete antioxidants, antiproteases, and inhibitors of cytokines. (psu.edu)
  • Macrophages can also release cytokines, which are small proteins that can cause inflammatory reactions and help to recruit more macrophages alongside other immune cells to the site of the infection. (medistudents.com)
  • Synovial macrophages produce a variety of pro-inflammatory cytokines that contribute to synovitis and can be targeted with therapeutic agents. (musculoskeletalkey.com)
  • The activation of macrophages leads to the production of T helper 1 (Th1) inflammatory cytokines such as tumor necrosis factor- (TNF-) α , interleukin- (IL-) 1 β , IL-6, and IL-12, whereas limited activation develops into a Th2 response (IL-4 secretion) [ 11 - 13 ]. (hindawi.com)
  • During infection, macrophages have diverse roles including phagocytosis of foreign bodies, release of cytotoxic factors, and coordination of the inflammatory response via the secretion of chemokines and cytokines ( 3 , 4 ). (frontiersin.org)
  • Phagocytes, cytokines (Th1 and inflammatory) and reactive nitrogen intermediates are the major antimicrobial mechanisms against tuberculosis infection. (fapesp.br)
  • For in vitro assay, we will evaluate the effects of LTB4 addition in infected alveolar macrophage to investigate the phagocitosis and microbicidal activity, as well the intracellular signaling involved in this mechanisms and the cytokines and lipid mediators production. (fapesp.br)
  • a set of quantitative signs of activation, previously developed in studies of inflammatory peritoneal macrophages, has been applied to the study of immunologically stimulated peritoneal cells. (liverpool.ac.uk)
  • Histone adsorption on the surface of carbon particles significantly stimulates their ingestion by rat peritoneal macrophages, hamster kidney fibroblasts, and mouse L-cells [ 861 ], and the adsorption of polycyclic aromatic hydrocarbons (PAHs) and their nonpolar metabolites on the surface of carbon particles ingested by rat alveolar macrophages has been studied [ 862 ]. (nanomedicine.com)
  • MWCNT particles, often associated with alveolar macrophages (AMs), were detected in the lungs of the exposed rats. (cdc.gov)
  • From there, it spreads to the mucous membranes of the throat and bronchial tubes, eventually entering the lungs where it infects type 2 alveolar epithelial cells called pneumocytes. (aging-us.com)
  • However, alveolar macrophages can also secrete factors called chemotaxins that attract PMN to the airways, and this supports a central role for alveolar macrophages in the regulation of PMN traffic in the lungs. (psu.edu)
  • That phagocytes are also important defenders of the lungs in vivo is best supported by the observations in immunodeficient patients and animal models. (psu.edu)
  • In conclusion, alveolar macrophages and PMN participate in both defense and injury processes of the lungs. (psu.edu)
  • The more serious disease of TLR4-regular mice led to improved influx of triggered macrophages and T cells towards the lungs and intensifying control of fungal burdens but impaired enlargement of regulatory T cells (Treg cells). (ap26113.com)
  • They describe a series of cells, including microglia that exist in the central nervous system as well as Kupffer cells in the liver and alveolar macrophages in the lungs amongst others. (medistudents.com)
  • Therefore these results suggest that alveolar macrophage products play a direct role in the initial recruitment of PMN into infected lungs. (clodrosome.com)
  • Round, granular, mononuclear phagocytes found in the alveoli of the lungs. (bvsalud.org)
  • At least two populations of tissue macrophages exist: tissue-resident cells that are embryonically derived and a monocyte-derived population. (musculoskeletalkey.com)
  • Aim of the present study was to investigate if the pre-coating of MWCNTs with pulmonary surfactant has an influence on potential adverse effects, upon both (i) human monocyte derived macrophages (MDM) monocultures, and (ii) a sophisticated in vitro model of the human epithelial airway barrier. (biomedcentral.com)
  • Lymphocytes, platelets, eosinophils, fibroblasts, epithelial and endothelial cells are also implicated in lung injury and repair, either independently or synergistically with macrophages and/or PMN. (psu.edu)
  • In particular, through the release of lymphokines, lymphocytes appear to play a central role in the regulation of both macrophages and PMN function in interstitial lung diseases. (psu.edu)
  • Significant lung pathology occurred with development of mixed mononuclear cellular aggregates (T and B lymphocytes, phagocytes) after repetitive dust exposure, a novel observation. (nebraska.edu)
  • In lymph node, lymph is filtered through phagocytes and lymphocytes into hilum, and then drained into efferent lymphatic vessel. (turkupetcentre.net)
  • Fig. 2: Recovery from infection is followed by susceptibility to secondary pneumonia and reduction in phagocytosis by alveolar macrophages in mice. (nature.com)
  • We used a combination of congenic monocyte adoptive transfer, and pulse-chase labeling of DNA, to determine the kinetics and characteristics of trafficking, differentiation, and infection of mononuclear phagocytes during the chronic, adaptive immune phase of M. tuberculosis infection in mice. (escholarship.org)
  • Mice received either adhesion-blocking Abs to inhibit alveolar leukocyte trafficking or liposomal clodronate to deplete alveolar macrophages before intratracheal application of native PLY or its noncytotoxic derivative PdB. (aai.org)
  • biochemical and functional characteristics of the plasma membrane of macrophages from bcg-infected mice. (liverpool.ac.uk)
  • Lavage fluid TNFα, IL-6, keratinocyte chemoattractant, and macrophage inflammatory protein-2 were significantly increased after single and repetitive dust exposures, but were dampened in 2-wk dust-exposed mice compared with single exposure. (nebraska.edu)
  • toggle_content title="Abstract"] To evaluate the role of alveolar macrophages (AMs) in acute Pseudomonas aeruginosa pneumonia in mice, AMs were depleted by aerosol inhalation of liposomes containing clodronate disodium. (clodrosome.com)
  • Additionally, the origin of synovial macrophages was linked to monocytes derived from the bone marrow, based on studies using radiation chimeras of beige mice. (musculoskeletalkey.com)
  • Moreover, parabiotic mice that share the same circulation showed that only a subset of macrophages such as heart, gut, and dermis exhibited a mixed population, whereas Langerhans cells, microglia, and alveolar macrophages were exclusively derived from the parent mouse. (musculoskeletalkey.com)
  • These studies were the first to provide support for an alternative hypothesis to the MPS regarding monocyte replacement and macrophage turnover in adult mice. (musculoskeletalkey.com)
  • Studies using radiation chimeras and parabiotic mice demonstrated that monocytes only populate tissue-resident macrophages in a few organs during steady-state conditions in adult mice. (musculoskeletalkey.com)
  • The origin of the adult tissue-resident macrophage, however, was unknown until the generation of fate-mapping and lineage-tracing mice. (musculoskeletalkey.com)
  • These lung macrophages are morphologically and functionally heterogenous and include alveolar, interstitial, intravascular, and airway macrophages, each with characteristic morphologic and functional features. (psu.edu)
  • The role of macrophage proteinases in the development of emphysema, a major component of COPD, will be discussed. (atsjournals.org)
  • Fig. 3: Phagocytosis function of newly formed resident lung alveolar macrophages is altered locally by secondary inflammatory mediators released during infection. (nature.com)
  • Fig. 6: Sirpa is required for the priming, but not the maintenance, of the paralysis program of alveolar macrophages after infection. (nature.com)
  • We propose that additional investigation into the role of ADCP in protective viral responses, the specific virus epitopes targeted by ADCP antibodies, and the types of phagocytes and Fc receptors involved in ADCP at sites of virus infection will provide insight into strategies to successfully leverage this important immune response for improved antiviral immunity through rational vaccine design. (frontiersin.org)
  • Our findings that mononuclear phagocyte populations at the site of M. tuberculosis infection are highly dynamic provide support for specific approaches for host-directed therapies directed at monocytes, including trained immunity, as potential interventions in TB, by replacing cells with limited antimycobacterial capabilities with newly-recruited cells better able to restrict and kill M. tuberculosis. (escholarship.org)
  • The contribution of phagocytes to the defense against infection and tumor has been documented mostly in vitro. (psu.edu)
  • Survival of the fungus inside the host's macrophages is essential for successful infection and depends on several features: the strain of the fungus, its responsiveness to external factors such as temperature changes and oxidative stress, and the efficiency of the host's immunological response [ 7 ]. (hindawi.com)
  • The study of macrophage-microbe interplay is thus crucial for understanding pathogenesis and infection control. (frontiersin.org)
  • Furthermore, the chemical and genetic tractability of zebrafish has been central to decipher the complex role of macrophages during infection. (frontiersin.org)
  • Macrophages are a major component of the innate immune system, responding efficiently to tissue damage and infection ( 1 , 2 ). (frontiersin.org)
  • Resident cells within the lung such as fibroblasts and alveolar type II cells may be induced by cigarette smoke to synthesize chemokines attracting and potentially activating inflammatory cells. (atsjournals.org)
  • It is now known that type A cells were synovial macrophages, type B were synovial fibroblasts, and type C were an undetermined population. (musculoskeletalkey.com)
  • We investigated the production of the chemotactic cytokine monocyte chemoattractant protein-1 (MCP-1) using sera, synovial fluid, synovial tissue, as well as macrophages and fibroblasts isolated from synovial tissues from 80 arthritic patients. (northwestern.edu)
  • To examine the cellular source of MCP-1, RA synovial tissue macrophages and fibroblasts were isolated. (northwestern.edu)
  • After resolution of primary pneumonia, murine alveolar macrophages (AMs) exhibited poor phagocytic capacity for several weeks. (nature.com)
  • M-CSF was first characterized as a glycoprotein that induces monocyte and macrophage colony formation from precursors in murine bone marrow cultures. (biolegend.com)
  • The depletion of splenic and hepatic murine macrophages by liposome-encapsulated clodronate (lip-clod) was studied as a new strategy for ITP treatment. (expressextension.com)
  • As phagocytosis by macrophages plays a critical role in the control of bacteria, we investigated the phagocytic activity of macrophages after resolution of inflammation. (nature.com)
  • Also, specific defects in phagocyte functions such as in chronic granulomatous disease (lack of oxidative burst) or in alveolar proteinosis (impaired phagocytosis by macrophages) are associated with severe infectious problems. (psu.edu)
  • Phagocytes describe a group of immune cells that are capable of phagocytosis. (medistudents.com)
  • Studies using zebrafish allow non-invasive, real-time visualization of macrophage recruitment and phagocytosis. (frontiersin.org)
  • Phagocytosis can involve the recognition of pathogen- and damage-associated molecular patterns (PAMPs and DAMPs, respectively) through pattern recognition receptors (PRRs) on the macrophage surface ( 5 , 6 ). (frontiersin.org)
  • Immunoreactive IFN-alpha was first seen at 9 weeks gestation in macrophages in the fetal liver and thereafter was seen in macrophages in most other organs except in kidneys and cerebral and cerebellar cortex. (gla.ac.uk)
  • Intratracheal administration of liposomal clodronate accelerates alveolar macrophage reconstitution following fetal liver transplantation. (expressextension.com)
  • These studies determined that adult monocytes develop as precursors in the bone marrow and then enter the circulation to replenish macrophages in tissue through the use of radiolabeled monocyte progenitors. (musculoskeletalkey.com)
  • The administration of nonlethal irradiation to induce death of hematopoietic cells and their precursors followed by administration of donor bone marrow (radiation chimeras) revealed populations of macrophages, including synovial macrophages, Langerhans cells, and microglia, that were resistant to irradiation and remained host origin, whereas the monocyte population was derived from donor hematopoietic cells. (musculoskeletalkey.com)
  • Histological photographs showed that oMWCNTs were mainly captured by lung macrophages, and NDs were located in the bronchi and alveoli after co-administration. (springer.com)
  • Through the presence of surface receptors for numerous ligands and through their large number of secretory products, lung macrophages can respond to environmental factors and account for most of the clearance of microparticles and microorganisms in the distal airways and the alveolar spaces. (psu.edu)
  • Fig. 4: T reg cells and TGF-β are not major contributors to the paralysis program of alveolar macrophages. (nature.com)
  • Largely the product of mononuclear phagocyte activation, it is unclear whether TNF-α production at disease sites is a feature of all mononuclear phagocytes that accumulate there or whether it is secreted by a subset of these cells. (ersjournals.com)
  • In children, the description of developmental changes in immune receptor expression on alveolar macrophages (AM) has been limited by the small number of cells recovered by bronchoalveolar lavage (BAL). (ersjournals.com)
  • Other particles may be engulfed by epithelial cells, primarily in the vicinity of the bronchial-alveolar duct junctions, and retained for much longer periods, with gradual removal to lymph nodes. (cdc.gov)
  • Many of these studies include the activity of immune effector cells, in particular of macrophages, when they are confronted with conidia of A. fumigus wild-type and mutant strains. (ilrs.de)
  • Macrophages can also contribute to the alveolitis by recruitment of inflammatory and immune cells. (psu.edu)
  • Because the capillary lumen is separated only from the alveolar space by a monolayer of endothelial and epithelial cells on each side of a thin interstitial matrix, it is likely that some inhibitory mechanism exists to prevent PMN from migrating towards the alveolar space. (psu.edu)
  • Kupffer cells, pulmonary alveolar macrophages and lymph node macrophages were also positive for IFN-alpha. (gla.ac.uk)
  • The alveolar macrophages will be the 1st sponsor cells that connect to cells and their activation can be fundamental towards the control of fungal development. (ap26113.com)
  • Kupffer cells, spanning the lumen of these sinusoids, are a type of macrophage that phagocytose aging red blood cells and other debris in the sinusoidal lumen. (digitalhistology.org)
  • There are cells, such as phagocytes, that can invade bodies in a process in which the cell uses its plasma membrane to engulf the large particle, giving rise to an internal compartment called a phagosome, and then activating the acquired immunity system by presenting a portion of the phagocytosed and digested foreign substances from its membrane surface. (encyclopedia.pub)
  • These memory B cells massively increase the numbers of T cells and macrophages so that they can specifically affect this pathogen, meaning that the organism can often be eradicated before symptoms occur, or if not, can prevent severe symptoms and side effects of the disease from occurring. (medistudents.com)
  • Macrophages are one of the main cells involved in the innate immune system. (medistudents.com)
  • Further studies in the 1980s and early 1990s refined the classification of synovial macrophages with the use of immunohistochemistry and known antibodies to antigen-presenting cells. (musculoskeletalkey.com)
  • Cells within the synovial tissue may recruit mononuclear phagocytes into the synovial fluid and tissues of arthritic patients. (northwestern.edu)
  • After the liposomes are digested by lysosomal phospholipases, the free clodronate released into the cells induces rapid apoptosis of the macrophages. (expressextension.com)
  • Apoptotic cells induce a phosphatidylserine-dependent homeostatic response from phagocytes. (docsbay.net)
  • However, studies in emphysema and in idiopathic pulmonary fibrosis suggest that oxidants and proteases (including elastase) derived from PMN and probably from alveolar macrophages contribute in vivo to lung matrix degradation. (psu.edu)
  • Moreover, coupling of LTB4 to its receptor leads to intracellular activation that induces phagocytes and bacterial killing. (fapesp.br)
  • Lung histological changes resulting from MWCNT exposure were mild and consisted mainly of interstitial accumulation of macrophages. (cdc.gov)
  • Two decades later, pioneering studies suggested that lectin-like molecules constitutively expressed on the surface of macrophages can selectively recognize changes on glycans decorating the surface of apoptotic thymocytes, 4 , 5 although these studies likewise did not provide substantial insight into the mechanisms by which lectin-glycan interactions regulate cell death. (nature.com)
  • In contrast, unlike normal peripheral blood monocytes or alveolar macrophages, RA synovial tissue macrophages constitutively expressed MCP-1 mRNA and antigen. (northwestern.edu)
  • Ex vivo stimulation of alveolar macrophages from 2-wk animals demonstrated reduced cytokine responsiveness and phagocytic ability. (nebraska.edu)
  • Zebrafish ( Danio rerio ) larvae provide a unique platform to study macrophage-microbe interactions in vivo , from the level of the single cell to the whole organism. (frontiersin.org)
  • In addition, depletion of resident alveolar macrophages with clodronated liposomes did not reduce alveolar injury developing in response to PLY. (aai.org)
  • To determine whether alveolar macrophage products are important in the initiation of chemotaxis, we depleted rats of alveolar macrophages by aerosolizing negatively charged oligolamellar liposomes complexed to clodronate disodium. (clodrosome.com)
  • Here we show that liposomes can also target the delivery of drugs to zebrafish macrophages to selectively manipulate their function. (expressextension.com)
  • research using clodronate liposomes to study or manipulate macrophage function will continuously be extended, there will be many scientists having information that could be of much help to other scientists in macrophage research. (expressextension.com)
  • These findings suggested that there is a basal level of IFN-alpha production by macrophages, which is not dependent on microbial products, but that such microbial products can enhance synthesis of this cytokine. (gla.ac.uk)
  • It really is known nevertheless that regular macrophages are permissive to development while cytokine-activated macrophages have the ability to restrain multiplication (12). (ap26113.com)
  • Levels of bioactive tumor necrosis factor-α and immunoreactive proteins CINC/gro (cytokine-induced PMN chemoattractant) in the lavage fluids obtained from infected rats depleted of alveolar macrophages were significantly decreased compared with the levels in the lavage fluids obtained from normal infected rats. (clodrosome.com)
  • No differences in the average levels of TNF-α secretion by peripheral blood monocytes or alveolar macrophages were observed. (ersjournals.com)
  • Emphysema is defined as enlargement of peripheral airspaces of the lung, including respiratory bronchioles, alveolar ducts, and alveoli, accompanied by destruction of the walls of these structures. (atsjournals.org)
  • A number of previous publications have demonstrated the upregulation of TNF-α in a variety of contexts including bronchoalveolar lavage (BAL) fluid protein, macrophage protein secretion and macrophage TNF messenger ribonucleic acid content 9 - 16 . (ersjournals.com)
  • The current paradigm is that the vast majority of macrophages are "tissue-resident," developing during embryogenesis and self-renewing in most tissues in the absence of inflammatory stimuli or severe depletion. (musculoskeletalkey.com)
  • It is concluded that laser scanning cytometry is suited to the study of immune receptor expression from small numbers of paediatric alveolar macrophages, when CD68 is used for cell identification. (ersjournals.com)
  • The measurement of developmental changes in alveolar macrophage (AM) immune receptor expression using flow cytometry (FC) in children is limited by several factors. (ersjournals.com)
  • Hence, phagocytes represent only one component of a complex network of cellular and humoral factors interacting in defense, injury, and immune reaction. (psu.edu)
  • The specific role of alveolar macrophages (AM) in modulating the local cellular immune response to antigens is controversial. (johnshopkins.edu)
  • These observations demonstrate that human AM might either enhance immune function or exert an antiphlogistic effect within the alveolar milieu in response to inhaled foreign antigens. (johnshopkins.edu)
  • Normally, macrophages represent the majority of phagocytes in the lower respiratory tract. (psu.edu)
  • The importance of these species in innate immunity was first recognized in phagocytes that underwent a "respiratory burst" after activation. (encyclopedia.pub)
  • The mycoplasma colonise the respiratory tract of the pig, gradually spreading down the bronchial tree, damaging the muco-ciliary escalator system, allowing the accumulation of material in the alveolar spaces, which cause the typical gross lesions. (octagon-services.co.uk)
  • Moreover, macrophages are prominent in the respiratory bronchioles of cigarette smokers, where emphysematous changes are first manifest. (atsjournals.org)
  • Most of those depositing in the gas-exchange region will be phagocytized by alveolar macrophages and cleared to and through the mucociliary escalator within a few weeks. (cdc.gov)
  • This study has demonstrated that a subset of mononuclear phagocytes, mature macrophages, are responsible for tumour necrosis factor secretion and this could have implications for targeted management in sarcoidosis in the future. (ersjournals.com)
  • Our data demonstrate that apoptotic cell instillation after bleomycin results in immediate and prolonged enhancement of PPAR mRNA and protein in alveolar macrophages and lung. (docsbay.net)
  • We also review novel aspects of macrophage biology revealed by zebrafish, which can potentiate development of new therapeutic strategies for humans. (frontiersin.org)
  • Scientific evidence from a variety of sources is emerging that supports a primary role for the macrophage in regulating the inflammatory response and tissue destruction associated with COPD. (atsjournals.org)
  • Immunohistochemical analysis of synovial tissue showed that a significantly greater percentage of RA macrophages (50±8%) as compared to either OA macrophages (5±2) or normal macrophages (1±0.3) reacted with anti-MCP-1 antibodies. (northwestern.edu)
  • LEADING SCIENTISTS IN LIPOSOME … In the first study: six animals were divided in two groups … Adipose tissue, as well as the liver, was investigated for macrophage infiltration and the presence of inflammatory mediators. (expressextension.com)
  • The analysis reported here, reveals that different mutants of A. fumigatus have a major influence on the ability of macrophages to adhere and to phagocytose the respective conidia. (ilrs.de)
  • When recombinant macrophage inflammatory protein (MIP-2) was intratracheally instilled into rats depleted of alveolar macrophages, PMN were recruited to their airspaces. (clodrosome.com)
  • or 4) a fluorescent-labelled monoclonal antibody to CD68, a pan-macrophage antigen. (ersjournals.com)
  • Reduced levels of TNF- α and IL-1 β and decreased expression of intercellular adhesion molecule- (ICAM-) 1, resulting in diminished interactions between the leukocyte and endothelium and reduced migration of phagocytes to inflammatory sites, have been suggested as possible causes for this increased susceptibility [ 19 - 21 ]. (hindawi.com)
  • Taken together, these fundamental studies provided the basis that the synovial macrophages were derived from hematopoietic progenitors and represented a heterogeneous population in both normal and inflamed synovium. (musculoskeletalkey.com)