Pascual M, Schifferli J A
Laboratory of Immunonephrology, Centre Médical Universitaire, Geneva, Switzerland.
Immunopharmacology. 1992 Sep-Oct;24(2):101-6. doi: 10.1016/0162-3109(92)90016-6.
Immune complexes, which have reacted with complement and bear C3b fragments, bind to the complement receptor 1 (CR1) on human erythrocytes. Indeed, CR1 on erythrocyte serves as a transport system for immune complexes in the circulation so as to prevent immune complex deposition outside the fixed macrophage system. A defect in this transport system has been described in several diseases, in which either complement levels or CR1 number on erythrocytes are diminished. Recent studies have shown that the binding of immune complexes to erythrocytes is favored by the multiple C3b binding sites per receptor and the clustered distribution of CR1 on the erythrocyte surface. Only a few immune complexes bind per erythrocyte but these complexes are tightly bound. The other main function of CR1 on erythrocytes is to enhance the inactivation of C3b by factor I present in plasma. This reaction allows the release of immune complexes from the erythrocyte surface and their transfer to fixed macrophages.
已与补体发生反应并带有C3b片段的免疫复合物，会与人红细胞上的补体受体1（CR1）结合。实际上，红细胞上的CR1充当循环中免疫复合物的转运系统，以防止免疫复合物沉积在固定巨噬细胞系统之外。在几种疾病中都描述了这种转运系统的缺陷，这些疾病中补体水平或红细胞上CR1的数量会减少。最近的研究表明，每个受体的多个C3b结合位点以及CR1在红细胞表面的聚集分布有利于免疫复合物与红细胞的结合。每个红细胞仅结合少数免疫复合物，但这些复合物结合紧密。红细胞上CR1的另一个主要功能是增强血浆中存在的I因子对C3b的灭活作用。该反应使免疫复合物从红细胞表面释放，并转移至固定巨噬细胞。
