Generation of C5-derived lysosomal enzyme-releasing activity (C5a) by lysates of leukocyte lysosomes.
Generation of C5-derived lysosomal enzyme-releasing activity (C5a) by lysates of leukocyte lysosomes.
复制标题
通过白细胞溶酶体裂解物产生 C5 衍生的溶酶体酶释放活性 (C5a)。
DOI：
10.4049/jimmunol.113.5.1583
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发表时间：
1974
影响因子：
4.4
通讯作者：
Gerald Weissmann
中科院分区：
文献类型：
--
作者：
I. M. Goldstein;Gerald Weissmann
白细胞溶酶体包含至少以两种方式与补体系统相互作用的物质，以产生C5衍生的溶酶体酶释放活性(C5a)。首先，溶酶体蛋白酶能够在中性pH条件下裂解纯化的C5，产生一种低分子产物，选择性地从细胞松弛素B处理的同源人多形核白细胞中释放溶酶体酶，而不是细胞质酶。该酶的活性被EACA和正常人血清抑制。其次，在新鲜血清中，溶酶体裂解产物产生C3激活剂的活性形式，并产生二硫苏糖醇处理的红细胞的非免疫性溶血，推测是通过激活替代途径。因此，作为补体激活的结果，经白细胞溶酶体裂解物处理的人血清中产生C5a活性：溶酶体成分在正反馈循环中进一步自身释放。
Leukocyte lysosomes contain materials which interact with the complement system in at least two ways to generate C5-derived lysosomal enzyme-releasing activity (C5a). Firstly, a lysosomal protease is capable of cleaving purified C5 at neutral pH to yield a low molecular weight product which selectively releases lysosomal, but not cytoplasmic, enzymes from isologous, cytochalasin B-treated, human polymorphonuclear leukocytes. The activity of this enzyme is inhibited by EACA and by normal human serum. Secondly, in fresh serum, lysosomal lysates generate the active form of the C3 proactivator and produce nonimmune hemolysis of dithiothreitol-treated erythrocytes, presumably by activation of the alternate pathway. Therefore, C5a activity is generated in human serum treated with lysates of leukocyte lysosomes as a consequence of complement activation: lysosomal constituents further their own release in a positive feed-back loop.