Siegel R C, Schumaker V N, Poon P H
J Immunol. 1981 Dec;127(6):2447-52.
We have examined the functional and hydrodynamic properties of the first component of human complement, C1, and the activated first component, C1-, reassembled in the presence of Ca++ from C1q and either the C1r2C1s2 or the C1r-2C1s-2 tetramer. Reconstituted C1 has hemolytic activity similar to C1 in serum. As long as either tetramer is in excess and the total concentration is low, we find that only a 1:1 complex is formed between C1q and either the unactivated or activated tetramer. This complex sediments at 15.9 +/- 0.2 Svedbergs and has a complex sediments at 15.9 +/- 0.2 Svedbergs and has a m.w. of 739,000 +/- 37,000. The boundary shape of the sedimenting C1- preparation was broader than that of C1 suggesting the association constant between C1r2C1s2 and C1q may have decreased upon activation. At elevated concentrations, with more than a molar excess of C1q, C1 aggregated to form both 16S and 23S species.
我们研究了人补体第一成分C1以及在钙离子存在下由C1q与C1r2C1s2或C1r - 2C1s - 2四聚体重新组装而成的活化第一成分C1 - 的功能和流体动力学特性。重组后的C1具有与血清中C1相似的溶血活性。只要任何一种四聚体过量且总浓度较低，我们发现C1q与未活化或活化的四聚体之间仅形成1:1复合物。该复合物在15.9±0.2斯维德伯格单位沉降，分子量为739,000±37,000。沉降的C1 - 制剂的边界形状比C1的更宽，这表明C1r2C1s2与C1q之间的缔合常数在活化后可能降低。在浓度升高时，当C1q摩尔过量时，C1聚集形成16S和23S物种。
