COMPLEMENT ACTIVATION OF THE GLOMERULER EPITHELIAL CELL

被动Heymann肾炎大鼠模型的建立 肾病，抗体(抗Fx1a)激活细胞表面补体 肾小球内脏上皮细胞(GEC)及其形成的细胞 损伤，从而导致蛋白尿的发展。文化中的GEC 含有限制补体激活的膜蛋白。很有可能 这些蛋白质也存在于体内，并起到保护 GEC既有自发的补体激活，也有抗体导向的补体激活。 有证据表明，抗Fx1a抗体在激活 GEC上的补体通过与a结合并抑制a 补充GEC的调节蛋白。 为了分离这些具有补体抑制活性的蛋白质， 培养的大鼠肾小管上皮细胞膜蛋白将受到不同程度的 层析步骤。抑制溶血中补体的能力 化验将指导这些蛋白质的分离。纯化后的抗体 然后，蛋白质将被提炼并测试它们抑制 调节补体，从而增强补体的激活，在 体外培养。这些抗体也将在体内进行研究。 探讨补充性法规在保护GEC方面的作用 在正常情况下和在依赖补体的疾病中 活动性、被动性海曼肾炎。特定的补语 通过抗Fx1a抗体鉴定的调节蛋白也将被分离出来。这个 抑制其正常功能在被动海曼中的作用 肾炎将被确诊。GEC的应对能力 通过增加这些蛋白的膜表达来激活补体 调节蛋白将在体外确定。最后，能力 以消除结合并抑制A细胞的抗体。 补体调节蛋白的细胞表面，将被 已评估。

In passive Heymann nephritis, a rat model of human membranous nephropathy, antibody (anti-Fx1A) activates complement on the surface of the glomerular visceral epithelial cell (GEC), with resultant cell injury and, consequently, the development of proteinuria. GEC in culture contain membrane proteins that limit complement activation. It is likely that these proteins are also present in vivo and serve to protect the GEC from both spontaneous and antibody-directed complement activation. Evidence exists that anti-Fx1A is particularly effective in activating complement on GEC by virtue of its binding to, and inhibiting, a complement regulatory protein of the GEC. In order to isolate these proteins with complement inhibitory activity, membrane proteins from cultured rat GEC will be subjected to various chromatographic steps. The ability to inhibit complement in a hemolytic assay will guide isolation of these proteins. Antibodies to purified proteins will then be raised and tested for their ability to inhibit the regulation of complement, thereby enhancing complement activation, in vitro. Studies will also be performed in vivo with these antibodies to explore the role complement regulation has in protecting GEC under normal circumstances and in a disease dependent upon complement activation, passive Heymann nephritis. The particular complement regulatory protein identified by anti-Fx1A will also be isolated. The role that inhibition of its normal function plays in passive Heymann nephritis will be established. The ability of the GEC to respond to complement activation by increasing membrane expression of these regulatory proteins will be determined in vitro,. Lastly, the capability of the GEC to eliminate antibody that has bound to, and inhibited, a complement regulatory protein of the surface of the cell, will be evaluated.