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Results 401 - 450 of 1084
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Stofanko Martin - - 2008
In Drosophila, defense against foreign pathogens is mediated by an effective innate immune system, the cellular arm of which is composed of circulating hemocytes that engulf bacteria and encapsulate larger foreign particles. Three hemocyte types occur: plasmatocytes, crystal cells, and lamellocytes. The most abundant larval hemocyte type is the plasmatocyte, ...
Stoeger Tobias - - 2009
The inhalation of combustion-derived nanoparticles (CDNPs) is believed to cause an oxidative stress response, which in turn may lead to pulmonary or even systemic inflammation. In this study we assessed whether the in vivo inflammatory response--which is generally referred to as particle toxicity-of mice to CDNPs can be predicted in ...
Menin Adams - - 2008
The supernatant from cultures of haemocytes of the compound ascidian Botryllus schlosseri incubated with zymosan (conditioned medium; CM) can enhance yeast phagocytosis by Botryllus blood cells. It contains molecules recognised by antibodies raised against the mammalian pro-inflammatory cytokines IL-1-alpha and TNF-alpha which appear as a single band of 60 kDa ...
Dale David C - - 2008
The production and deployment of phagocytes are central functions of the hematopoietic system. In the 1950s, radioisotopic studies demonstrated the high production rate and short lifespan of neutrophils and allowed researchers to follow the monocytes as they moved from the marrow through the blood to become tissue macrophages, histiocytes, and ...
Janko C - - 2008
Deficiencies in the recognition and phagocytosis of dead and dying cells have been shown to be one of the main alterations in patients with systemic lupus erythematosus (SLE). Cellular as well as humoral elements play an important role in the clearance of apoptotic and necrotic cells. Non-ingested nuclear material may ...
Wang Wei - - 2008
The antiviral effectiveness of three major immune responses including phagocytosis, apoptosis and proPO system in the shrimp Marsupenaeus japonicus was characterized. It was found that the suppression of apoptosis and phagocytosis in vivo by their corresponding inhibitors resulted in the increase of white spot syndrome virus (WSSV) copies and shrimp ...
Perri Daniella - - 2008
Cytokines play a major role in the immune response by activating mononuclear phagocytes. The aim of this study was to determine the effects of cytokines on Fc-gamma receptor (FcgammaR)-mediated phagocytosis of IgG1- or IgG3-sensitized red blood cells (RBCs). The results show a large variation in human monocyte phagocytosis independent of ...
Frey Benjamin - - 2009
Proteins of the annexin family bind to phospholipids in a Ca(2+) dependent manner. The exposure of phosphatidylserine (PS) by apoptotic as well as necrotic cells is one major eat-me-signal for macrophages. Annexin A5 (Anx A5) preferentially binds to PS. The availability of Anx A5 knock out (KO) mice allowed us ...
Cong Ming - - 2008
It is well known that invertebrates are devoid of adaptive immune components and rely primarily on innate immunity to defend against pathogens, but recent studies have demonstrated the existence of enhanced secondary immune protection in some invertebrates. In the present study, the cumulative mortality of scallops received two successive Listonella ...
Shah Abhishek S - - 2008
Immunomodulatory activity of methanolic extract of M. koenigii leaves was evaluated on humoral and cell mediated immune response to ovalbumin, phagocytic activity by carbon clearance test, nitric oxide (NO) release from murine peritoneal macrophages and cyclophosphamide induced myelosuppression. Significant increase in the NO production by mouse peritoneal macrophages was detected ...
Goulaouic S - - 2008
It has been suggested that the organic fraction of particulate matter in air pollution has a major role in the toxicity of this pollutant, notably via its effects on inflammation. The major organic compounds adsorbed onto these particles are polycyclic aromatic hydrocarbons (PAH), among which benzo[a]pyrene (B[a]P), benzo[b]fluoranthene (B[b]F), and ...
Park Seung-Yoon - - 2008
Exposure of phosphatidylserine (PS) on the cell surface occurs early during apoptosis and serves as a recognition signal for phagocytes. Clearance of apoptotic cells by a membrane PS receptor is one of the critical anti-inflammatory functions of macrophages. However, the PS binding receptors and their recognition mechanisms have not been ...
Steinberg Benjamin E - - 2008
Phagocytosis is a key component of the innate immune response and of the clearance of apoptotic bodies. Phagosome formation and subsequent maturation require extensive cytoskeletal rearrangement and precisely choreographed vesicular fusion and fission events. The objectives of this review are to highlight the functional importance of lipids in the phagocytic ...
Fan, Xiaoxuan
Phosphatidylserine (PS) has been found on apoptotic cells and macrophages. PS on both cells is required for phagocytosis. It was asked whether bivalent annexins, which bind PS in a Ca2+-dependent manner, could bridge the target cell and macrophage. Monoclonal antibodies (mAbs) against annexins I or II bound to a variety ...
Delgado-Vélez Manuel - - 2008
We have shown previously that whereas acute exposure of cultured murine peritoneal macrophages inhibits phagocytosis, chronic exposure results in a putative tolerant/dependent state. We now report similar observations using human cultured monocyte-derived macrophages (hMDM) from a control population and from methadone patients. With hMDM, acute exposure to morphine and methadone ...
Grabowski Julia E - - 2008
BACKGROUND: Laparoscopic surgery is currently used in an array of diverse clinical situations, including cases with potential bacterial contamination. Previous studies have shown that CO2 insufflation during laparoscopic procedures modulates the immune response due to the acidification of the peritoneum. In the present study, we investigated whether exposure of macrophages ...
Kocbach Anette - - 2008
Lung inflammation is an important process in host defence to inhaled particulate matter. To what extent physicochemical properties of particles from different sources influence their inflammatory potential has not been fully clarified. The aim of this study was to investigate the potential of particles from wood smoke and traffic to ...
Ostachuk Agustín - - 2008
Exposure to particulate matter (PM) may alter lung homeostasis inducing changes in fluid balance and host defense. Bioavailability of soluble PM compounds like polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and transition metals has been shown to play a key role in lung injury. We have previously characterized the size, ...
Flierl Michael A - - 2008
It is well established that catecholamines (CAs), which regulate immune and inflammatory responses, derive from the adrenal medulla and from presynaptic neurons. Recent studies reveal that T cells also can synthesize and release catecholamines which then can regulate T cell function. We have shown recently that macrophages and neutrophils, when ...
Shiratsuchi Akiko - - 2008
Mannose-binding lectin (MBL) exists in the serum as a complex with MBL-associated serine protease (MASP). A recent paper described how MASP-free recombinant rat MBL stimulates the phagocytosis of Escherichia coli and Staphylococcus aureus by rat Kupffer cells through an increase in the level of a phagocytosis receptor. We have examined ...
Hermann Petra M - - 2008
Activation of phagocytic cells in the injury zone is a crucial step in the regeneration of peripheral axons. Many aspects of the mechanisms underlying the recruitment of active phagocytes remain, however, unclear. Notably, our understanding of the interactions between injury, extracellular matrix (ECM) degradation and phagocyte activation is limited. Most ...
Stuart Lynda M - - 2008
Phagocytosis, the engulfment of material by cells, is a highly conserved process that arose before the development of multicellularity. Phagocytes have a key role in embryogenesis and also guard the portals of potential pathogen entry. They discriminate between diverse particles through the array of receptors expressed on their surface. In ...
Mitschik S - - 2008
In recent years evidence has accumulated indicating that airborne particles cause adverse health effects. To understand the underlying mechanisms, a multitude of in vitro studies have been performed focusing on inflammatory responses, especially cytokine production. However, the diversity of studies renders it difficult to determine which results are consistent and ...
Maier Konrad Ludwig - - 2008
In this article, we review and analyze different modes of exposure to ultrafine particles in order to assess particle-induced inflammatory responses and the underlying mechanisms in vitro and in vivo. Based on results from monocytic cells cultured under submerged conditions, we discuss (1) the impact of particle properties such as ...
Zinkernagel Annelies S - - 2008
Hypoxia-inducible factor (HIF)-1alpha is activated on exposure to bacterial pathogens and regulates the innate immune functions of phagocytes. We show here that the HIF-1alpha agonist mimosine can boost the capacity of human phagocytes and whole blood to kill the leading pathogen Staphylococcus aureus in a dose-dependent fashion and reduce the ...
Kubica Malgorzata - - 2008
Although considered to be an extracellular pathogen, Staphylococcus aureus is able to invade a variety of mammalian, non-professional phagocytes and can also survive engulfment by professional phagocytes such as neutrophils and monocytes. In both of these cell types S. aureus promptly escapes from the endosomes/phagosomes and proliferates within the cytoplasm, ...
Deretic Vojo - - 2008
Autophagy and phagocytosis are evolutionarily ancient processes functioning in capture and digestion of material found in the cellular interior and exterior, respectively. In their most primordial form, both processes are involved in cellular metabolism and feeding, supplying cells with externally obtained particulate nutrients or using portions of cell's own cytoplasm ...
Frankenberg Tobias - - 2008
Phagocytosis and intracellular destruction of pathogens by phagocytes is a crucial defense mechanism of the innate immune response during infection. It has been reported a number of times that the interaction with pyogenic, extracellular bacteria leads to the apoptotic death of phagocytes. The signaling events that cause this form of ...
Ghoneum M - - 2008
Phagocytic cells, comprised of neutrophils and monocytes/macrophages, play a key role in the innate immune response to infection. Our earlier study demonstrated that arabinoxylan rice bran (MGN-3/Biobran) activates murine peritoneal macrophage and macrophage cell lines. In this study, we investigated whether MGN-3 can upregulate the phagocytic activity of human phagocytes ...
Koziel Henry - - 2008
Alveolar macrophages are "professional phagocytes" and critical effector cells that protect the lungs from a broad array of microbes that can cause severe respiratory tract infections such as pneumonia. The molecular mechanisms that mediate microbial phagocytosis in alveolar macrophages are not fully known, and the specific role of small Rho ...
Li Zhaojie - - 2008
Vitellogenin (Vg), a major reproductive protein, has been associated with infection-resistant response in fish. However, the underlying mechanisms by which Vg is involved in anti-infectious response are not understood. By both protein-microbe interaction analysis and enzyme-linked immunosorbent assay as well as phagocytosis test, we demonstrate for the first time that ...
Levin Milton - - 2008
The immunotoxic potential of domoic acid (DA), a well-characterized neurotoxin, has not been fully investigated. Phagocytosis and lymphocyte proliferation were evaluated following in vitro and in vivo exposure to assay direct vs indirect effects. Mice were injected intraperitoneally with a single dose of DA (2.5 microg/g b.w.) and sampled after ...
Jayachandran Rajesh - - 2008
Macrophages are crucial for innate immunity, apoptosis, and tissue remodeling, processes that rely on the capacity of macrophages to internalize and process cargo through phagocytosis. Coronin 1, a member of the WD repeat protein family of coronins specifically expressed in leukocytes, was originally identified as a molecule that is recruited ...
Olazabal Isabel María - - 2008
The array of phagocytic receptors expressed by macrophages make them very efficient at pathogen clearance, and the phagocytic process links innate with adaptive immunity. Primary macrophages modulate antigen cross-presentation and T-cell activation. We assessed ex vivo the putative role of different phagocytic receptors in immune synapse formation with CD8 naïve ...
Chung Elaine Y EY Department of Microbiology and Immunology, Medical College of Cornell University, New York, NY 10065, - - 2007
Production of interleukin (IL)-10, a major immunoregulatory cytokine, by phagocytes during clearance of apoptotic cells is critical to ensuring cellular homeostasis and suppression of autoimmunity. Little is known about the regulatory mechanisms in this fundamental process. We report that IL-10 production stimulated by apoptotic cells was regulated at the point ...
Ravichandran Kodi S - - 2007
The clearance of apoptotic cells by phagocytes is an integral component of normal life, and defects in this process can have significant implications for self tolerance and autoimmunity. Recent studies have provided new insights into the engulfment process, including how phagocytes seek apoptotic cells, how they recognize and ingest these ...
Allina Jorge - - 2008
Primary biliary cirrhosis is characterized by chronic hepatic inflammation and immune mediated apoptosis of bile duct epithelial cells. Delayed macrophage phagocytosis of opsonized apoptotic cells, noted in other autoimmune diseases, may promote inflammation. Recent studies suggest serum anti-CD16 autoantibodies contribute to impaired macrophage phagocytosis by blocking complement receptor 3 (CR3) ...
Yoshizaki Fumiko - - 2008
The innate immune system is the first line of defense against pathogenic microorganisms, such as bacteria, fungi, and viruses. Phagocytes, such as neutrophils and macrophages, play an important role in the innate immune system by recognizing, engulfing, and eliminating pathogens. It has been suggested that lipid membrane microdomains/rafts of phagocytes ...
Kocbach A - - 2008
Inflammation is considered as a key event in adverse health effects associated with exposure to ambient particulate matter. The inflammatory potential of particles is often compared using in vitro cell systems, where the particle-induced release of pro-inflammatory cytokines is measured. A major concern in these assays is the potential of ...
Fadeel Bengt - - 2007
Phagocytosis of apoptotic cell corpses is a conserved and well-regulated process and is required to maintain tissue homeostasis within an organism. Evidence suggests that apoptotic cell engulfment by macrophages is dependent upon the externalization of phosphatidylserine (PS) on the plasma membrane of the dying cell. Furthermore, oxidation of PS and ...
Bianchi Stephen M SM Academic Unit of Respiratory Medicine, School of Medicine and Biomedical Sciences, University of Sheffield, Sheffield S10 2JF, - - 2008
Cystic fibrosis lung disease is characterized by accumulation of apoptotic neutrophils, indicating impaired clearance of dying cells. Pseudomonas aeruginosa, the principal microbial pathogen in cystic fibrosis, manipulates apoptosis induction via production of toxic metabolites. Whether these metabolites, particularly pyocyanin, can also modulate apoptotic cell engulfment is unknown. To assess the ...
Silva Elizabeth E Medical Research Council Cell Biology Unit, MRC Laboratory for Molecular Cell Biology, Anatomy and Developmental Biology Department, University College London, London WC1E 6BT, - - 2007
Many cells die by apoptosis during animal development. Apoptotic cells are rapidly removed through phagocytosis by their neighbors or by macrophages. To genetically dissect this process, we performed an in vivo screen for genes required for efficient phagocytosis of apoptotic cells by Drosophila macrophages and identified pallbearer (pall), which encodes ...
Savina Ariel - - 2007
Like macrophages and neutrophils, dendritic cells (DCs) are considered professional phagocytes. Even if the three cell types phagocytose parasites, bacteria, cell debris, or even intact cells very efficiently, the functional outcomes of the phagocytic event are quite different. Macrophages and neutrophils scavenge and destroy phagocytosed particles, a critical step in ...
LAMBERT, Christophe
Bivalve hemocyte competence has been measured by quantifying functional characteristics, including reactive oxygen intermediate (ROI) production after activation with zymosan or phorbol myristate acetate (PMA). However, untreated oyster hemocytes also produce ROI and RNI (reactive nitrogen intermediates) after bleeding even if not stimulated by Zymosan or PMA. Extensive investigation of ...
Anand Rahul J - - 2007
Phagocytosis is the process by which microbial pathogens are engulfed by macrophages and neutrophils and represents the first line of defense against bacterial infection. The importance of phagocytosis for bacterial clearance is of particular relevance to systemic inflammatory diseases, which are associated with the development of hypoxia, yet the precise ...
Rezende T M B - - 2007
AIM: To assess the influence of co-culture with mineral trioxide aggregate (MTA) on phagocytosis and the production of reactive oxygen intermediates (ROI) and nitrogen (NO) species and the arginase activity by M1 and M2 peritoneal macrophages. METHODOLOGY: Cellular viability, adherence and phagocytosis of Saccharomyces boulardii were assayed in the presence ...
Petrovski Goran - - 2007
Autophagy as a natural part of cellular homeostasis usually takes place unnoticed by neighboring cells. However, its co-occurrence with cell death may contribute to the clearance of these dying cells by recruited phagocytes. Autophagy associated with programmed cell death has recently been reported to be essential for presentation of phoshatidylserine ...
Kim Dong-Hwan DH Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, NC 27708, - - 2007
This in vitro study characterized the temporal cytokine expression profile from human monocytes exposed to phagocytosable Ti particles (0.78+/-0.12 microm) and to Ti discs of comparable surface roughness. Human THP-1 monocytes were cultured in six well tissue culture polystyrene (TCPS) plates. Each well was either bare, contained Ti particles (the ...
de las Heras B - - 2007
BACKGROUND AND PURPOSE: The kaurane diterpenes foliol and linearol are inhibitors of the activation of nuclear factor kappaB, a transcription factor involved in the inflammatory response. Effects of these diterpenes on apoptosis and phagocytosis have been analysed in cultured peritoneal macrophages and in the mouse macrophage cell line, RAW 264.7. ...
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