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31.
To investigate a potential role of osteopontin (OPN) in developing rat brain, the expression of OPN mRNA and protein in the developing rat brain relative to the distribution of brain macrophages was investigated using in situ hybridization and immunohistochemistry, and the phagocytic capability of OPN-expressing cells was accessed using rhodamine isothiocyanate (RhIc) as a tracer. OPN-expressing cells appeared from embryonic day 16. During the first week of postnatal life, OPN-labeled cells increased markedly, and peaked around P7, then declined and had completely disappeared by the end of the second postnatal week. The spatiotemporal distribution pattern of OPN mRNA closely matched that of OPN protein. Their morphology and localization were compared with those of cells expressing the established microglial marker OX-42 in adjacent sections, and double-labeling studies demonstrated that OPN was localized to the amoeboid microglia which stain with the lectin GSI-B4, another marker for microglia. Furthermore, OPN-labeled cells were confirmed to be active phagocytes emitting RhIc fluorescence indicating that the tracer into the brain tissues was engulfed by phagocytosis. Therefore, these results provide the first evidence that OPN is transiently expressed in active brain macrophages in the embryonic and early postnatal brain, and suggest that OPN may contribute to the migration and phagocytic function of brain macrophages in the developing brain.This work was supported by a Korea Research Foundation grant (KRF-2002-015-EP0106)  相似文献   
32.
Institute of Chemical Physics, Academy of Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR S. M. Navashin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 108, No. 9, pp. 330–332, September, 1989.  相似文献   
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Azuma Y  Ohura K 《Inflammation》2002,26(5):223-232
We evaluate immunological effects of opioid peptide endomorphin-2 on the production of cytokines related to inflammation and Th1/Th2 balance, and functions related to innate immune of rat peritoneal macrophages. Endomorphin-2 inhibited TNF-, IL-10, and IL-12 productions, but potentiated IL-1 production by macrophages. Moreover, endomorphin-2 potentiated macrophage adhesion to fibronectin, and the expression of adhesion molecule Mac-1 on macrophages. In contrast, endomorphin-2 suppressed phagocytosis of opsonized E. coli by macrophages, without affecting phagocytosis of non-opsonized E. coli. In addition, endomorphin-2 inhibited macrophage chemotaxis, and the production of superoxide anion by macrophages. These results suggest that endomorphin-2 may alter macrophage functions such as cytokine productions and functions related to innate immune.  相似文献   
35.
Mononuclear cells of the lamina propria (LpMNC), isolated from endoscopically taken biopsies of the large bowel from AIDS patients, were analysed for their ability to secrete tumour necrosis factor-alpha (TNF-alpha), IL-1 beta and IL-6. Stimulation of LpMNC from normal controls with pokeweed mitogen (PWM) led to a time- and dose-dependent enhancement of TNF-alpha, IL-1 beta and IL-6 secretion. In contrast, PWM stimulation of LpMNC from AIDS patients resulted in only a small increase in TNF-alpha release. Constitutive secretion of IL-1 beta and IL-6 in these patients was already increased to the concentration range of stimulated cells from normal controls and could not be further increased, probably due to maximal in vivo stimulation. Secretion of TNF-alpha, IL-1 beta and IL-6 by peripheral blood monocytes (PBM) and alveolar macrophages from AIDS patients was elevated with or without stimulation compared with normal controls. Obviously, the regulation of TNF-alpha secretion is dependent on the microenvironment. Since it is known that interferon-gamma (IFN-gamma) may induce the production of TNF-alpha, the secretion of this cytokine was examined. Release of IFN-gamma was constitutively and under stimulation lowered in LpMNC from AIDS patients compared with normal controls. Addition of IFN-gamma to LpMNC did not result in enhanced TNF-alpha secretion. Our data indicate a defective function of intestinal mononuclear cells in AIDS patients as shown by the diminished TNF-alpha secretion.  相似文献   
36.
BACKGROUND: Human follicular fluid contains several substances, such as cytokines and growth factors, which may affect follicular growth and maturation. The present study examines the relative contribution of macrophages and granulosa cells in the production of vascular endothelial growth factor (VEGF) and adrenomedullin in the human ovulatory follicle. METHODS: Both follicular fluid samples and blood samples were obtained at the time of oocyte retrieval following ovarian stimulation from 20 women undergoing IVF treatment because of male infertility. Human follicular fluid macrophages and luteinized granulosa cells were obtained from pooled follicular fluid of individual patients. Accumulation of VEGF and adrenomedullin in the culture medium of the isolated macrophages and human granulosa cells was determined at variable time intervals ranging from 0 to 48 h. Plasma and follicular fluid concentrations of VEGF and adrenomedullin were also measured. RESULTS: The follicular fluid concentrations of VEGF and adrenomedullin were significantly higher than those found in plasma. After 48 h, accumulation of VEGF in the culture medium of follicular fluid macrophages was significantly higher than that released in the culture medium of luteinized granulosa cells. In contrast, the production rate of adrenomedullin by follicular fluid macrophages was similar to that found in granulosa cells. VEGF secreted by follicular fluid macrophages increased progressively within 48 h of cell culture. A similar response pattern was observed with the culture medium of luteinized granulosa cells, but with lower production rates. CONCLUSIONS: This study suggests for the first time that both luteinized granulosa cells and macrophages actively secrete VEGF and adrenomedullin into follicular fluid in the human ovary.  相似文献   
37.
38.
The activating action of liquid BCG vaccine, lyophilized BCG vaccine, and killed BCG cells on macrophages was studied. Activation of mouse peritoneal macrophages was identified by their cytotoxic actionin vitro on syngeneic tumor target cells labeled with51Cr. Macrophages obtained from mice two to three weeks after a single injection of liquid BCG vaccine were shown to have a cytotoxic action on tumor cells. A single injection of lyophilized BCG vaccine or killed BCG cells into mice did not cause activation of their macrophages. Two injections of liquid or lyophilized BCG vaccine caused activation of macrophages much earlier — three to five days after the second injection. Intraperitoneal injection of BCG activated macrophages to a greater degree than subcutaneous injection.Laboratory of Experimental Tumor Therapy, P. A. Gertsen Moscow Oncologic Research Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR A. D. Timofeevskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 87, No. 1, pp. 36–39, January, 1979.  相似文献   
39.
Recently, we identified increased cathepsin X expression in H. pylori-infected gastric mucosa. Here, we describe further up-regulation in gastric cancer and report on the role of inflammatory cytokines required for cathepsin X up-regulation in H. pylori-infected gastric mucosa, as well as on consequences for cellular invasion. Biopsy specimens were taken from the antrum, corpus and cardia of H. pylori-infected and non-infected patients. Gastric cancer samples were obtained from patients undergoing gastric surgery. Cathepsin X was detected in gastric mucosa by quantitative real-time RT-PCR, western blotting and immunohistochemistry. Induction of cathepsin X expression in epithelial and inflammatory cells caused by H. pylori infection was tested in in vitro contact and non-contact co-cultures of AGS cells and monocytic cells. Patients with H. pylori gastritis showed significantly higher cathepsin X mRNA (2.5-fold) and protein (1.6-fold) expression than H. pylori-negative patients. Cathepsin X was also up-regulated in gastric cancer (3-12-fold) compared to non-neoplastic mucosa. Cathepsin X was predominantly expressed by macrophages in the mucosal stroma and in glands of the antral mucosa. In addition, tumour cells stained for cathepsin X in 26 (68%) patients with gastric carcinoma. In general, staining was significantly more common (20 vs. 6 patients) and more intense (3.55 vs. 0.83) in intestinal type gastric cancer than in the diffuse type. In vitro cell culture experiments revealed that intercellular signalling between pathogenicity island (PAI)-positive H. pylori-infected epithelial cells and macrophages via soluble factors in the culture medium seems to be responsible for increased expression of cathepsin X in monocytes. Using antisense oligonucleotides, cathepsin X up-regulation was directly associated with higher invasiveness in vitro. Although no correlation of cathepsin X expression and TNM stage was found, our study demonstrates that cathepsin X plays a role not only in the chronic inflammation of gastric mucosa but also in the tumourigenesis of gastric cancer.  相似文献   
40.
Prostaglandin E1 (PGE1) suppresses macrophage infiltration and ameliorates injury in an experimental model of macrophage dependent glomerulonephritis. Macrophages are mediators of glomerular injury in models of proliferative glomerulonephritis. We have recently shown that macrophages in glomerulonephritis have low prostaglandin E2 (PGE) generation, and other evidence implicates eicosanoids as regulators of macrophage activation. Here we have studied in rats the effect of 15(s)-15-methyl PGE1 (M-PGE1) on accelerated nephrotoxic nephritis, a model of acute macrophage-dependent glomerular injury. M-PGE1 ameliorated proteinuria (day 4; 61 +/- 13 mg/24 h, n = 9; vehicle treated, 164 +/- 17 mg/24 h, n = 11; P less than 0.002) and glomerular hypercellularity; quantification of infiltrating macrophages by isolating glomerular cells showed reduction in the numbers of macrophages (44 +/- 9/glomerulus; vehicle treated, 119 +/- 15/glomerulus; P less than 0.02) with inhibition of Ia antigen expression on infiltrating macrophages (8 +/- 5%; vehicle treated 25 +/- 4% P less than 0.05). Glomerular binding of nephrotoxic globulin and levels of autologous antibodies were not affected by M-PGE1. Thus the mechanism of suppression involves inhibition of macrophage accumulation and activation. M-PGE1 administered to normal rats did not affect numbers of resident leucocytes (12.6 +/- 1.5/glomerulus; vehicle treated, 13.2 +/- 1.3/glomerulus) or alter Ia antigen expression (4.1 +/- 0.2 Ia + cells/glomerulus; vehicle treated, 3.9 +/- 0.6/glomerulus). This study suggests a therapeutic role for PGE1 in this type of glomerulonephritis, and has implications for the pathophysiology of macrophage-mediated inflammation.  相似文献   
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