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61.
CD137 (ILA/4-1BB), expressed by primary human monocytes, induces monocyte activation and apoptosis of B lymphocytes 总被引:11,自引:0,他引:11
Human CD137 is a member of the tumor necrosis factor (TNF) receptor family and the homologue of murine 4-1BB. Recent studies have demonstrated that CD137 promotes accessory T cell activation, and regulates proliferation and survival of T lymphocytes. This study reports on the expression and function of CD137 in peripheral blood monocytes. While monocytes showed constitutive expression in 10 out of 18 healthy donors, CD137 was not expressed on resting T or B lymphocytes. Immobilized antibodies to CD137 markedly induced the production of IL-8 and TNF-alpha protein and mRNA, and led to inhibition of IL-10 expression by primary monocytes. Furthermore, cross-linking of CD137 on monocytes resulted in an increase of B lymphocyte apoptosis mediated by direct cell-cell contact of both cell populations. In conclusion, this study identified CD137 as a new receptor involved in monocyte activation by inducing a characteristic cytokine release profile. In addition, CD137 may play a role in monocyte-dependent control of B lymphocyte survival. 相似文献
62.
Bogsan CS Novaes e Brito RR Palos Mda C Mortara RA Almeida SR Lopes JD Mariano M 《International journal of experimental pathology》2005,86(4):257-265
The mechanisms that govern giant cell (GC) formation in inflammatory, neoplastic and physiologic conditions are far from being understood. Here, we demonstrate that B-1 cells are essential for foreign-body GC formation in the mouse. GCs were analysed on the surface of glass cover slips implanted into the subcutaneous tissue of the animals. It was demonstrated that GCs are almost absent on cover slips implanted into the subcutaneous tissue of BALB/c or CBA/N X-linked immunodeficient mice. As these animals do not have B-1 cells in the peritoneal cavity, they were reconstituted with B-1 cells obtained from cultures of adherent mouse peritoneal cells. Results showed that in B-1-reconstituted animals, the number of GCs on the implant surface surpassed the values obtained with preparations from wild animals. In animals selectively irradiated (pleural and peritoneal cavities) to deplete these cavities of B-1 cells, GCs were also not formed. Enriched suspensions of B-1 cells grown in culture were labelled with [(3)H]-tymidine and injected into the peritoneal cavity of naive mice before implantation of glass cover slips. After 4 days, about 17% of mononuclear cells had their nuclei labelled, and almost 70% of GCs had one or more of their nuclei labelled when analysed by histoautoradiographic technique. A few GCs expressed an immunoglobulin M when analysed by immunostaining and confocal microscopy. Overall, these data demonstrate that B-1 cells are pivotal in the mechanisms of foreign-body GC formation in the mouse. 相似文献
63.
64.
Saleh A Wiedermann D Schroeter M Jonkmanns C Jander S Hoehn M 《NMR in biomedicine》2004,17(4):163-169
Brain inflammation contributes to the tissue injury caused by ischemic stroke. Macrophages as the most abundant inflammatory cell population in stroke lesions can be visualized using ultrasmall superparamagnetic iron oxide (USPIO) as a cell-specific contrast agent for magnetic resonance imaging (MRI). The aim of our present study was to delineate the inflammatory response during experimental cerebral infarction by means of USPIO-enhanced MRI and to correlate the spatial distribution of USPIO-induced MR signal alterations with cellular infiltration and iron deposition. To this end USPIOs were administered to Wistar rats 5 days after photothrombotic cerebral infarction. MR imaging at 7 T performed 24 h later displayed a rim-like signal loss around the infarction in the USPIO treated animals. On histological brain sections obtained from the same animals after MRI the distribution of iron and ED1+ phagocytes was in full spatial agreement with the signal loss seen on T2*-weighted images. Our study validates USPIO-enhanced MRI as an important tool for the noninvasive visualization of brain inflammation in stroke and other CNS pathologies. 相似文献
65.
Induction of NO synthesis in macrophages by Newcastle disease virus is associated with activation of nuclear factor-{kappa}B 总被引:3,自引:0,他引:3
Umansky Victor; Shatrov Vladimir A.; Lehmann Volker; Schirrmacher Volker 《International immunology》1996,8(4):491-498
Newcastle disease virus (NDV) has received much attention recentlybecause of its non-specific immune stimulating potential andits various anti-tumor activities. Here we describe that NDVinduces synthesis of NO and causes an activation of nuclearfactor-kB (NF-kB) In murine macrophages. These reactions werepart of an activation process which included also stimulationof adenosine deaminase and inhibition of 5'-nucleotidase. NDV-mediatedNO synthesis and NF-kB activation were blocked by an antioxidant(butylated hydroxyanisole), by an inhibitor of protein tyrosinekinase (genistein) and of protein kinase A (H-89), but not byan inhibitor of protein kinase C (staurosporin). These datasuggest that signalling requirements of NF-kB activation andNO production in NDV-treated macrophages are similar. 相似文献
66.
Morphometric and immunohistochemical characterization of the intimal layer throughout the arterial system of elderly humans 总被引:3,自引:0,他引:3
Aryan Vink Arjan H. Schoneveld Marieke Poppen Dominique P. V. de Kleijn Cornelius Borst Gerard Pasterkamp 《Journal of anatomy》2002,200(1):97-103
The purpose of the present study was to obtain insight into the natural development of adaptive intimal thickening and atherosclerosis in the arterial tree of human species. The morphometry and composition of the intimal layer were studied in the arterial system of elderly individuals. Post mortem, a total of 703 arterial segments were dissected from 24 subjects (age 81.9 ± 9.9 years). From each subject, segments were dissected from 31 different arteries. Area stenosis [(plaque area/vessel area) × 100%] was determined in each segment. By (immuno)histochemistry, lipid content and the presence of inflammatory cells (macrophages) were assessed in the coronary, common carotid, brachial, radial and internal iliac arteries. Adaptive intimal thickening or advanced atherosclerosis was observed in all studied artery types. Area stenosis was highest in the coronary arteries (median, 30%) and lowest in the arteries supplying the brain (median, ≤ 7%). Plaques hiding a lipid‐rich core and plaques with macrophage infiltration were observed in all five selected artery types. In summary, the present observation demonstrates that intimal thickening is a systemic process involving most artery types. Within elderly humans, features of advanced atherosclerotic disease, a lipid‐rich core and macrophages, can be observed in the intimal layer of artery types that are recognised for their relation with clinical syndroms as well as artery types that remain clinically silent. 相似文献
67.
68.
The Yin-Yang of tumor-associated macrophages in neoplastic progression and immune surveillance 总被引:5,自引:1,他引:5
Paola Allavena Antonio Sica Cecilia Garlanda Alberto Mantovani 《Immunological reviews》2008,222(1):155-161
Summary: An intrinsic (oncogene-driven) pathway and an extrinsic (microenvironment-driven) pathway connect inflammatory reactions and cancer. M2-polarized tumor-associated macrophages and the related myeloid-derived suppressor cells are key prototypic components of smoldering inflammation driving neoplastic progression. However, mononuclear phagocytes can exert anti-tumor activity by killing tumor cells and eliciting tissue disruptive reactions (M1), a likely scenario in the early phases of carcinogenesis of immunogenic tumors and following therapeutic intervention. Shifting the macrophage balance represents a viable therapeutic target. Herein, the 'macrophage balance' is discussed in the context of the apparent paradox of tumor promotion by innate immunity-driven inflammation and the seemingly opposed tumor surveillance by adaptive immune responses. 相似文献
69.
L. G. Krymskaya N. Yu. Gromykhina V. A. Kozlov 《Bulletin of experimental biology and medicine》1988,105(3):366-367
Laboratory of Regulation of Immunopoiesis, Institute of Clinical Immunology, Siberian Branch, Academy of Medical Sciences of the USSR, Novosibirsk. (Presented by Academician of the Academy of Medical Sciences of the USSR V. P. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 105, No. 3, pp. 311–313, March, 1988. 相似文献
70.
M. R. Krotkova R. A. Abramova A. V. Sorokin 《Bulletin of experimental biology and medicine》1978,86(6):1628-1630
The effect of rabbit leukocytic pyrogen (LP) on the phagocytic activity of peritoneal macrophages from albino mice toward shigellas was investigated. The effect was found to depend on dose: LP in a large dose inhibited phagocytosis whereas small doses of LP were not very effective; the addition of LP to macrophages in average doses, after administration of kanamycin, stimulated both the phase of ingestion and the phase of digestion of the shigellas. Stimulation of phagocytosis by LP was accompanied by an increase in the activity of the lysosomal enzyme acid phosphatase in the macrophages; changes in the RNA content were not significant.Department of General Pathology, Institute of Experimental Medicine, Leningrad. Department of Infectious Diseases, I. P. Pavlov First Leningrad Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR P. N. Veselkin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 86, No. 12, pp. 700–703, December, 1978. 相似文献