C1 inhibitor-dependent dissociation of human complement component C1 bound to immune complexes.
C1 inhibitor-dependent dissociation of human complement component C1 bound to immune complexes.
复制标题
C1 抑制剂依赖性人补体成分 C1 与免疫复合物结合的解离。
作者：
Robert B Sim;G. Arlaud;M. Colomb
用125i标记的C1亚组分检测C1抑制剂与与免疫复合物结合的补体组分C1的相互作用。该抑制剂与子组分C1s结合迅速，与子组分C1r结合较慢。C1r-C1抑制剂复合物的形成导致亚组分C1r和C1s从抗体-抗原组分C1聚集体中快速解离。释放的速率和程度与C1抑制剂浓度成正比，也取决于离子强度。以纯化的C1抑制剂、血浆或血清作为C1抑制剂的来源，所得结果具有密切的可比性。在相同的条件范围内，只观察到C1q子组分的轻微解离。讨论了释放现象的含义与组分C1的结构和C1子组分的差异周转的可能性有关。
The interaction of C1 inhibitor with complement component C1 bound to immune complexes was examined by using 125I-labelled C1 subcomponents. The inhibitor binds rapidly to subcomponent C1s, and more slowly to subcomponent C1r. Formation of the C1r-C1 inhibitor complex causes rapid dissociation of subcomponents C1r and C1s from the antibody-antigen-component C1 aggregate. The rate and extent of this release are proportional to C1 Inhibitor concentration and are also dependent on ionic strength. Results obtained with purified C1 Inhibitor, plasma or serum as source of C1 Inhibitor are all closely comparable. Only slight dissociation of subcomponent C1q is observed under the same range of conditions. The implications of the release phenomenon are discussed in relation to the structure of component C1 and the possibility of differential turnover of C1 subcomponents.