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Franc Nathalie C - - 2002
Phagocytosis is the necessary corollary of apoptosis. It leads to the clearance of apoptotic cells by phagocytes, which can be 'professional' or 'amateur'. I review the known molecular aspects of phagocytosis of apoptotic corpses in mammals, Caenorhabditis elegans and Drosophila melanogaster from the point of view of the phagocyte and ...
Bergman M - - 2002
The capacity of rat peritoneal macrophages to produce interleukin-1beta (IL-1beta) following phagocytosis of latex particles in vivo and in vitro was examined. In both cases, a marked increase in IL-1beta secretion was observed, although the level of the cytokine secreted in vivo was higher than that observed after incubation of ...
Monks Jenifer - - 2002
The processes by which the involuting mammary gland clears residual milk and milk fat, as well as apoptotic cells, have gone largely unstudied in the modern literature. Here we review the evidence for and against the involvement of professional phagocytes of hematopoietic lineage in this process. Additionally we present evidence ...
Manfredi A A - - 2002
Cells continuously die and disappear from the midst of living tissues. However, some of their constituents survive. DNA is horizontally transferred to phagocytic cells, and apoptotic cell antigens shape the immune repertoire. When massive apoptosis occurs, which overwhelms tissue scavenger cells, or when the function of phagocytes abates, dying cells ...
Akisue Toshihiro - - 2002
Orthopedic wear debris has been thought to be an important factor associated with osteolysis and loosening of total joint arthroplasties. Previous in vitro studies have reported that particles of wear debris induce the release of pro-inflammatory cytokines and other inflammatory mediators from macrophages and other cells. Several recent investigations, however, ...
Brooks R A - - 2002
Particulate prosthetic materials are often studied by adding them to monocytic cells in vitro and measuring the release of cytokines as an indicator of their inflammatory potential. Endotoxin is known to be a contaminant of particle preparations and also stimulates the release of cytokines. It is usual to use a ...
Zhdanova E V - - 2002
We studied biological rhythms of immunological parameters and absorption and digestive activities of neutrophils and monocytes in women during the menstrual cycle. Circadian rhythms of phagocytosis were evaluated. The phagocytic system was characterized by highest activity during ovulation and early luteal phase of the menstrual cycle accompanied by physiological immunosuppression. ...
Vonk Alieke G - - 2002
Polymorphonuclear neutrophils (PMN) and mononuclear phagocytes represent an important first line and effector function in the control of Candida infections. Their relative contribution to host defence is frequently assessed by means of microbiological assays. However, reported results are divergent and might well be associated with study design-related issues. In the ...
Grottkau B E - - 2002
Macrophages play numerous roles in both physiologic and pathologic processes. Along with fibroblasts, they comprise the synovial tissue that forms the lining of musculoskeletal joint capsules and bursae, and they often envelop implants. During the process of phagocytosing prosthesis-related particles, macrophages in peri-implant tissue release inflammatory mediators. Little is known, ...
Greenberg Steven - - 2002
Phagocytosis is an evolutionarily conserved process utilized by many cells to ingest microbial pathogens, and apoptotic and necrotic corpses. Recent investigation has revealed a fundamental requirement for two co-ordinated cellular processes--cytoskeletal alterations and membrane trafficking--in the phagocytic event. Some elements of this machinery are co-opted by certain pathogens to gain ...
Huynh Mai-Lan N - - 2002
Ingestion of apoptotic cells in vitro by macrophages induces TGF-beta1 secretion, resulting in an anti-inflammatory effect and suppression of proinflammatory mediators. Here, we show in vivo that direct instillation of apoptotic cells enhanced the resolution of acute inflammation. This enhancement appeared to require phosphatidylserine (PS) on the apoptotic cells and ...
Ma Nan - - 2002
Their unique mechanical and biological properties make polyurethanes (PUs) ideal materials for many implantable devices. However, uncertain long-term biostability in the human physiological environment limits their extensive clinical applications. Chronic inflammatory response associated with macrophage activation has been suggested as a prime factor; although the mechanism of macrophage activation in ...
Voyich Jovanka M - - 2002
Polymorphonuclear leukocytes (PMNs) are a critical component of the human innate immune response and are the first line of defense against invading microorganisms. Phagocytosis of invading microbes induces production of reactive oxygen species (ROS) by PMNs, which facilitates bactericidal activity. In addition to eliminating microorganisms, phagocytosis also accelerates PMN apoptosis, ...
Wooley Paul H - - 2002
An in vivo model of the inflammatory response to orthopaedic biomaterials was used to examine cellular and cytokine responses to polymer particles of ultra high molecular weight polyethylene (UHMWPE) and polymethylmethacrylate (PMMA), and metal particles of cobalt-chrome (Co-Cr) and titanium alloy (Ti-6Al-4V). Responses were determined separately and in combinations, to ...
Petit Alain - - 2002
We recently identified apoptosis in in vitro wear particle-stimulated macrophages. The recent explosion of interest in apoptosis lies in the fact that it is under positive and negative regulation through evolutionary conserved biochemical pathways. It may also be possible to modulate macrophage apoptosis in the treatment of periprosthetic osteolysis. The ...
Vandana Shah
We previously reported that Pycnogenol<SUP>®</SUP>, procyanidins extracted from the bark of French maritime pine (Pinus maritima Aiton; the official botanical name is now <I>Pinus pinaster </I>Aiton) is a potent free radical scavenger. It has been shown to inhibit macrophage oxidative burst. Macrophages carry out their microbicidal and tumoricidal activities via ...
Schwoebel, Frank
The uptake of apoptotic cells by professional phagocytes like macrophages is not only a non-inflammatory but also an active anti-inflammatory process. a)To examine these immunomodulating effects of dying cells an in vitro co-culture system using primary murine cells was established. b)Co-incubation of macrophages with apoptotic cells followed by stimulation with ...
Underhill David M - - 2002
The phagocytic response of innate immune cells such as macrophages is defined by the activation of complex signaling networks that are stimulated by microbial contact. Many individual proteins have been demonstrated to participate in phagocytosis, and the application of high-throughput tools has indicated that many more remain to be described. ...
Fadok V A - - 2001
Apoptosis is a genetically controlled event taking care of cell turnover in healthy adult tissues and of focal elimination of cells during embryonic development. The initial phase of the program leads to corpse generation and is followed by the equally crucial removal by phagocytes. In fact, engulfment is not mere ...
Bartl M M - - 2001
Phagocytosis of apoptotic, senescent, and dying cells by macrophages is a well characterized process. More recently it has been shown that in addition to macrophages vital neighboring cells in the affected tissue participate in the cellular clearance. While scavenger receptors have been shown to mediate uptake into macrophages, it is ...
Neumann N F - - 2001
Phagocytosis is a primitive defense mechanism in all multicellular animals. Phagocytes such as macrophages and neutrophils play an important role in limiting the dissemination of infectious agents, and are responsible for the eventual destruction of phagocytosed pathogens. These cells have evolved elaborate killing mechanisms for destroying pathogens. In addition to ...
Reichner J S - - 2001
Experiments were conducted to test the hypothesis that opsonic and non-opsonic phagocytic capacities are differentially regulated by resting and wound-derived macrophages. Furthermore, the phagocytosis of non-opsonized zymosan and beta-glucan particles was quantified to determine whether cells differentially regulate non-opsonic lectinophagocytosis in accordance with the carbohydrate composition of the ligand. In ...
Brown D M - - 2001
Studies into the effects of ultrafine particles in the lung have shown adverse effects considered to be due in part to the particle size. Air pollution particles (PM(10)) are associated with exacerbations of respiratory disease and deaths from cardiovascular causes in epidemiological studies and the ultrafine fraction of PM(10) has ...
van Eeden S F - - 2001
Elevated levels of ambient particulate matter (PM(10)) have been associated with increased cardiopulmonary morbidity and mortality. We previously showed that the deposition of particles in the lung induces a systemic inflammatory response that includes stimulation of the bone marrow. This marrow response is related to mediators released by alveolar macrophages ...
Becher R - - 2001
Rat lung alveolar macrophages and type 2 cells were exposed for 20 h in vitro to various stone particles with differing contents of metals and minerals (a type of mylonite, gabbro, feldspar, and quartz). The capability to induce the release of the inflammatory cytokines interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-alpha), ...
Hetland R B - - 2001
The mechanisms for particle-induced health effects are not well understood, but inflammation seems to be of importance. Previously, we have shown that stone quarry particles with various mineral and metal content differed widely in potency to induce inflammatory cytokines (IL-6, IL-8 and TNF-alpha) in different types of lung cells. In ...
Alexander E H - - 2001
Staphylococcus aureus is the primary etiological agent of several human diseases. S. aureus has classically been considered an extracellular pathogen; however, recent evidence indicates that S. aureus invades and persists in non-professional phagocytes. Experiments demonstrate that actin microfilaments, microtubules, receptor-mediated endocytosis, and protein tyrosine kinases play important roles in the ...
Trindade M C - - 2001
Periprosthetic membranes commonly observed at sites of total joint implant loosening exhibit abundant macrophages and particulate debris. Macrophages phagocytose orthopedic debris and release the pro-inflammatory mediators interleukin-1, interleukin-6, tumor necrosis factor-alpha, and prostaglandin E2. Populations of activated lymphocytes are often seen in periprosthetic membranes. These lymphocytes may modulate the monocyte/macrophage ...
Smith M E - - 2001
The microglial cell, after many years of neglect, has become recognized as the sole representative cell of the immune system that resides in the normal central nervous system. While normally dormant, microglia can be activated by secretory substances or signals associated with disease or injury, and becomes a phagocytic cell, ...
Giles K M - - 2001
Phagocytic clearance of apoptotic granulocytes has a pivotal role in determining an inflammatory outcome, resolution or progression to a chronic state associated with development of fibrotic repair mechanisms, and/or autoimmune responses. In this study, we describe reprogramming of monocyte to macrophage differentiation by glucocorticoids, resulting in a marked augmentation of ...
Kurosaka K - - 2001
It is generally believed that apoptosis is not associated with inflammation. However, we have found that phagocytosis of apoptotic cells by PMA-treated THP-1 cells and human monocyte-derived macrophages led to the production of proinflammatory cytokines, notably IL-8. These macrophages were obtained either by PMA treatment or by M-CSF treatment, possibly ...
Ninomiya J T - - 2001
Cytokines and proteases are secreted by fibroblasts in response to particulate wear debris, and these proteins are felt to play an important role in the development of osteolysis and implant loosening. Although metallic and polyethlyene debris have been studied extensively, little is known about the cellular responses to hydroxyapatite, despite ...
Stoika R - - 2001
BACKGROUND: Phagocytes (polymorphonuclear cells and monocyte-macrophages) are the first line of defence of the host against infectious microorganisms and other foreign antigens. Agents which participate in activation of phagocytic cells possess a potential immunomodulating action. Thus, search for convenient in vitro test-systems and study of mechanisms of action of these ...
Lee D H - - 2001
Corrosion and wear of implanted medical devices may produce particulate debris, leading to acute and chronic inflammatory responses in the host. In the presence of biomaterial wear particles, host monocytes/macrophages are activated to synthesize or secrete mediators of inflammation. In order to understand the mechanisms underlying the host response to ...
Schlegel R A - - 2001
Virtually every cell in the body restricts phosphatidylserine (PS) to the inner leaflet of the plasma membrane by energy-dependent transport from the outer to the inner leaflet of the bilayer. Apoptotic cells of all types rapidly randomize the asymmetric distribution, bringing PS to the surface where it serves as a ...
Moghimi S M - - 2001
The rapid recognition of intravenously injected colloidal carriers, such as liposomes and polymeric nanospheres from the blood by Kupffer cells, has initiated a surge of development for "Kupffer cell-evading" or long-circulating particles. Such carriers have applications in vascular drug delivery and release, site-specific targeting (passive as well as active targeting), ...
Scott R S - - 2001
Apoptosis is fundamental to the development and maintenance of animal tissues and the immune system. Rapid clearance of apoptotic cells by macrophages is important to inhibit inflammation and autoimmune responses against intracellular antigens. Here we report a new function for Mer, a member of the Axl/Mer/Tyro3 receptor tyrosine kinase family. ...
Campbell P A - - 2001
This unit presents fairly simple assays for measuring the binding of bacteria to macrophages, internalization of bacteria (also called ingestion or phagocytosis), and bacterial killing by macrophages. The first basic protocol describes how to measure the ability of macrophages to ingest bacteria. Because it is critical to remove residual extracellular ...
Uchida H - - 2001
The Fcgamma receptor (FcgammaR)-mediated phagocytosis of macrophages is a complex process where remodeling of both the actin-based cytoskeleton and plasma membrane occur coordinately. Several different families of small GTPases are involved. We have isolated a GTPase-activating protein (GAP) for ADP-ribosylation factor (ARF), paxillin-associated protein with ARFGAP activity (PAG)3/Papalpha/KIAA0400, from mature ...
Renwick L C - - 2001
We investigated whether slowed clearance after exposure to ultrafine particles was due to a failure in alveolar macrophage phagocytosis. This was achieved by measuring the ability of a macrophage cell line (J774.2 MPhi) to phagocytose 2-microg indicator latex beads following 8-h exposures to a number of test particles. Particles utilized ...
May R C - - 2001
The process of engulfing a foreign particle - phagocytosis - is of fundamental importance for a wide diversity of organisms. From simple unicellular organisms that use phagocytosis to obtain their next meal, to complex metazoans in which phagocytic cells represent an essential branch of the immune system, evolution has armed ...
Soukup J M - - 2001
Inhalation of particulate matter in the ambient air has been shown to cause pulmonary morbidity and exacerbate asthma. Alveolar macrophage (AM) are essential for effective removal of inhaled particles and microbes in the lower airways. While some particles minimally effect AM function others inhibit antimicrobial activity or cause cytokine and ...
Wallace P K - - 2001
Studies from our laboratory and others have established that both mononuclear phagocytes and neutrophils mediate very efficient cytotoxicity when targeted through Fc receptors using a suitable monoclonal or bispecific antibody (BsAb). Cross-linking an Fc receptor for IgG (FcgammaR) triggers multiple anti-tumor activities including superoxide generation, cytokine and enzyme release, phagocytosis ...
Fadok V A - - 2001
Removal of apoptotic cells during tissue remodeling or resolution of inflammation is critical to the restoration of normal tissue structure and function. During apoptosis, early surface changes occur, which trigger recognition and removal by macrophages and other phagocytes. Loss of phospholipid asymmetry results in exposure of phosphatidylserine (PS), one of ...
Bukovsky M - - 2001
The study presents comparison of immunomodulatory effects of Staphylococcus aureus, Escherichia coli and Candida albicans disintegrated cells on selected immune mechanisms of human and mouse leukocytes. We measured their phagocytic activity, phagocytic index and microbicidal activity against Staphylococcus aureus, Escherichia coli and Candida albicans cells as well as peroxidase and ...
van Zijverden M - - 2000
Particulate air pollutants may play a role in the increasing prevalence of respiratory allergy by acting as adjuvants for a T helper 2 (Th2) mediated immune response to common allergens. The immunomodulating capacity of well-defined polystyrene particles as well as different particles as present in our environment (diesel exhaust, carbon ...
Matthews J B - - 2000
The response of primary human peripheral blood mononuclear phagocytes to challenge with clinically relevant ultra-high molecular weight polyethylene (UHMWPE) wear debris of known particle size and dose was evaluated. Particles with a mean size of 0.24, 0. 45, 1.7, 7.6, and 88 microm were cocultured with cells for 24 h ...
Boynton E L - - 2000
Osteolysis remains the most important problem in orthopedic implant failure. Wear debris from the implant contains polyethylene (PE) particulate which has been shown to activate monocyte-derived macrophages (MDM). Although the response of MDM has been shown to be influenced by the size, shape, and chemical type of PE, the effect ...
Sansonetti PJ - - 2000
Advances in Cell and Molecular Biology of Membranes and Organelles Volume 5 - Phagocytosis: the Host edited by Alan M. Tartakoff; volume editor, Siamon Gordon JAI Press Inc./Ablex Publishing Corp. (1999) pp. 521. ISBN 1-55938-999-0 $147.50 Over the last few years, cell biology has become a dominant approach in several ...
Ernst J D - - 2000
The concerted study of molecular mechanisms of phagocytosis and the inhibition of phagocytosis by specific products of extracellular bacterial pathogens has borne considerable fruit. The importance of tyrosine phosphorylation and of the Rho family of GTPases has become clear to cell biologists, but pathogenic bacteria recognized the importance of these ...
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