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In the present study, we examined the effect of CsA on the in vitro production of Ig and on the in vitro production of molecules known to have B-cell growth and differentiation activities, such as IL-6 and sCD23. For the purpose of this study, we developed an experimental In vitro system closely resembling an In vivo model of ongoing B-cell activation. Pre-activated B cells proliferated and produced IgM optimally when they were re-cultured in the presence of IL-2/IL-6. CsA down-regulated the IL-2/IL-6-induced proliferative responses of pre activated B cells by at least 50%., but it up-regulated IgM production in the same experiments. This up regulating effect was not cytokine-related since it was also seen when cells were re-cultured in the absence of any cytokines. Optimal release of sCD23 was observed when SAC-pre-activated B cells were re cultured in the presence of IL-4 or IL-4 plus IL-2 and CsA up-regulated significantly the release of this molecule in these cultures. Finally, CsA was shown to inhibit PHA-induced cell proliferation of PBMC and to up-rcgulate IL-6 production in the same cultures. We conclude that CsA can amplify in vitro both the production of Ig and the release of sCD23 by pre activated B cells. This finding, in combination with the CsA-induced up-regulation of lectin-induced IL-6 production, may have clinical implications in disease states with an ongoing immune activation, where prolonged administration of CsA might be anticipated.  相似文献   
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To investigate the role of cell-mediated immunity (CMI) in glomerulonephritis (GN), we identified the infiltrating immune cells both within the glomerulus and in the interstitium. Frozen sections from 103 patients with various forms of GN: 10 with minor glomerular abnormality (MGA) as control, 10 with minimal change nephrotic syndrome (MCNS), 10 with membranous nephropathy (MN), 9 with focal glomerulosclerosis (FGS), 30 with IgA nephropathy (IgAN), 22 with acute post streptococcal glomerulonephritis (APSGN), and 2 with rapidly progressive glomerulonephritis (RPGN) were examined using monoclonal antibodies (MoAb) by indirect immunoalkaline-phosphatase labelling. In most glomerulonephritis, monocyte/M phi and helper/inducer T cells were predominantly infiltrating in the interstitium, but intraglomerular infiltration was rare, except for APSGN. This interstitial infiltration increased proportionally to the level of serum creatinine, and was most prominent in RPGN. Apparently different distribution was seen in APSGN, that is, prominent increase in total number of intra-glomerular monocyte/M phi infiltration with slightly increased T cells. The change was correlated with time after onset; namely the more leucocytic infiltration was observed when the tissue was taken earlier. These data suggest that in APSGN, monocyte/M phi accumulate in glomeruli via cell mediated immunity in addition to humoral immune mechanism resulting in glomerular hypercellularity, whereas in most chronic glomerulonephritis interstitial leucocyte infiltration, particularly helper T cells and monocyte/M phi may play an important role in the progression of glomerulonephritis.  相似文献   
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In experiments on albino rats it was established that three administrations of indomethacin in a dose of 0.01 g/kg body weight induced a severe damage of the liver characterized by disturbances of hepatocytic membranes, bile-producing and protein-producing functions of the liver, an enhancement of lipid peroxidation, a decrease of reduced glutathione pool. Antioxidants (tocopherol acetate, essentiale, legalon, flacumin) limit manifestations of indomethacin, hepatotoxicity, as a result of which tha functional-biochemical disorders in the liver show up to a lesser degree. During the combined use of antioxidants in indomethacin-induced lesions of the liver their hepatoprotective activity increases.  相似文献   
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A chemically defined medium for the culture of mature oligodendrocytes   总被引:3,自引:0,他引:3  
A new chemically defined medium consisting of equal parts of Dulbecco modified Eagle's and Ham's F-12 media supplemented with insulin, sodium selenite, putrescine, and D+ galactose, which allows the long-term survival of mature oligodendrocyte pure cultures, is described. Immunohistochemical staining has shown that over 90% of the cells become positive for myelin proteins shortly following subculture. Contaminating astrocytes (2%) do not survive in this medium. Biochemical data have indicated that these purified oligodendrocytes express 2'3'-cyclic nucleotide 3'-phosphohydrolase and UDP-galactose ceramide galactosyltransferase activities. Electron microscopical examination revealed that the oligodendrocytes were mostly of medium-dark type and appeared to be identical to cells cultured in serum-containing medium. The ability to maintain pure oligodendrocyte cultures in such a defined medium will allow investigations concerning exogenous and endogenous factors involved in oligodendrocyte metabolism.  相似文献   
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