Maeda M, Muro H, Shirasawa H
Department of Pathology, Hamamatsu University School of Medicine, Japan.
Cell Tissue Res. 1988;254(3):543-51. doi: 10.1007/BF00226504.
Involvement of C1q in retaining immune complexes in germinal centers in rat spleen was studied in vivo and in vitro. C1q production was found in fibroblastic reticulum cells in the peripheral mantle zone, in follicular dendritic cells in germinal centers, and in transitional forms between these two cells in the inner mantle zone. In passively immunized animals, immune complexes were found transiently on fibroblastic reticulum cells, then on the transitional forms and follicular dendritic cells. Extracellular C1q was detected by the presence of immune complexes on both the transitional forms and follicular dendritic cells, but not on fibroblastic reticulum cells. Thus, the fibroblastic reticulum cell appeared to trap immune complexes but not to retain either immune complexes or C1q. The morphology and function of the fibroblastic reticulum cell and the follicular dendritic cell suggest that they belong to the same lineage. Immune complexes were bound in vitro to germinal centers in cryostat spleen sections in the same manner as those retained in vivo. The binding required no complement in the incubation medium and was inhibited by C1q-suppressing factors. The extracellular C1q originating from the follicular cells may therefore play a role in retaining immune complexes in the germinal center.
在体内和体外研究了C1q在大鼠脾脏生发中心保留免疫复合物中的作用。在外周套区的成纤维网状细胞、生发中心的滤泡树突状细胞以及内套区这两种细胞之间的过渡形式中发现了C1q的产生。在被动免疫的动物中，免疫复合物先短暂出现在成纤维网状细胞上，然后出现在过渡形式细胞和滤泡树突状细胞上。通过过渡形式细胞和滤泡树突状细胞上存在免疫复合物检测到细胞外C1q，但在成纤维网状细胞上未检测到。因此，成纤维网状细胞似乎捕获免疫复合物，但不保留免疫复合物或C1q。成纤维网状细胞和滤泡树突状细胞的形态和功能表明它们属于同一谱系。免疫复合物在体外以与体内保留的相同方式结合到低温恒温器脾脏切片中的生发中心。这种结合在孵育培养基中不需要补体，并且受到C1q抑制因子的抑制。因此，源自滤泡细胞的细胞外C1q可能在生发中心保留免疫复合物中起作用。
