替代补体激活
中文名称
通路描述
参与替代途径激活的蛋白包括 C3（和 C3b），因子 B、D 和 Properdin。首先，替代途径激活是一种正反馈机制以增加 C3b。当 C3b 共价结合到细胞表面的糖时，它可以被保护起来。然后因子 B 结合到 C3b。在有因子 D 存在的情况下，结合到 C3b 的因子 B 被切割成 Ba 和 Bb。Bb 包含 C3 转化酶的活性位点。Properdin 然后结合到 C3bBb 以稳定 C3bBb 转化酶在细胞表面，导致 C3 的切割。最后，C3bBb3b 复合物形成，这是一个 C5 转化酶。
英文描述
Alternative complement activation The proteins participating in alternative pathway activation are C3 (and C3b), the factors B, D, and properdin. In the first place, alternative pathway activation is a positive feedback mechanism to increase C3b. When C3b binds covalently to sugars on a cell surface, it can become protected. Then Factor B binds to C3b. In the presence of Factor D, bound Factor B is cleaved to Ba and Bb. Bb contains the active site for a C3 convertase. Properdin then binds to C3bBb to stabilize the C3bBb convertase on cell surface leading to cleavage of C3. Finally, a C3bBb3b complex forms and this is a C5 convertase.
所含基因
5 个基因