Cross-linking CD21/CD35 or CD19 increases both B7-1 and B7-2 expression on murine splenic B cells.
Cross-linking CD21/CD35 or CD19 increases both B7-1 and B7-2 expression on murine splenic B cells.
复制标题
DOI：
10.4049/jimmunol.160.4.1565
复制
发表时间：
1998-02
影响因子：
4.4
通讯作者：
Y. Kozono;Y. Kozono;R. Abe;H. Kozono;Robert G. Kelly;T. Azuma;V. Holers
中科院分区：
文献类型：
--
作者：
Y. Kozono;Y. Kozono;R. Abe;H. Kozono;Robert G. Kelly;T. Azuma;V. Holers
补体级联的激活和补体C3受体的连接是天然免疫和抗原特异性获得性免疫之间的重要桥梁。我们发现，小鼠CD21(补体受体2型，CR2，C3d受体)和CD35(补体受体1型，CR1，C3b/C4b受体)或CD21/CD35和表面IgM共同交联会迅速上调小鼠静息脾B细胞上B7-1和B7-2的表达。CD21/CD35介导的B7-1和B7-2表达在14小时内均上调，而其他刺激在这一早期时间点仅上调B7-2而不上调B7-1。与B7水平的升高一致，表面IgM和CD21/CD35共交联物的BALB/c B细胞比对照组更有效地刺激C57BL/6T细胞。这种CD21/CD35增强的同种异体MLR几乎完全被抗B7-2单抗阻断，部分被抗B7-1单抗阻断。此外，与CD21/CD35物理上相关的CD19的交联会导致B7-1和B7-2表达增加。这些数据表明，CD21/CD35通过与其他激活剂共享的共刺激机制导致B细胞抗原提呈增强，从而在这一过程中协同发挥作用。快速上调B7-1的表达，这是对CD21/CD35和CD19交联的一种独特反应，可能是C3配体的一个特别重要的作用。我们认为CD21/CD35和CD19介导的B7-1和B7-2上调是补体激活连接先天免疫和获得性免疫的重要机制。
Activation of the complement cascade and ligation of complement C3 receptors on B cells represent an important bridge between innate and Ag-specific acquired immunity. We show here that cross-linking of mouse CD21 (complement receptor type 2, CR2, C3d receptor) and CD35 (complement receptor type 1, CR1, C3b/C4b receptor) or co-cross-linking of CD21/CD35 and surface IgM rapidly up-regulates both B7-1 and B7-2 expression on murine resting splenic B cells. CD21/CD35-mediated up-regulation of both B7-1 and B7-2 expression is observed within 14 h, while other stimuli up-regulate only B7-2 but not B7-1 at this early time point. Consistent with the increase in B7 levels, BALB/c B cells on which surface IgM and CD21/CD35 have been co-cross-linked stimulate C57BL/6 T cells more effectively than controls. This CD21/CD35-enhanced allogeneic MLR is blocked nearly completely by anti-B7-2 mAbs and partially by anti-B7-1 mAbs. In addition, cross-linking of CD19, which is physically associated with CD21/CD35, leads to increased B7-1 and B7-2 expression. These data suggest that CD21/CD35 ligation results in enhanced B cell Ag presentation using costimulatory mechanisms shared with other activators and thus works cooperatively in this process. Rapid up-regulation of B7-1 expression, a unique response to CD21/CD35 and CD19 cross-linking, may be a particularly important effect of C3-containing ligands. We propose that CD21/CD35- and CD19-mediated B7-1 and B7-2 up-regulation is an important mechanism by which complement activation links innate and acquired immunity.