A tetrameric form of CD40 ligand with potent biological activities in both mouse and human primary B cells
A tetrameric form of CD40 ligand with potent biological activities in both mouse and human primary B cells
复制标题
四聚体形式的 CD40 配体，在小鼠和人类原代 B 细胞中具有有效的生物活性
DOI：
10.1016/j.molimm.2018.11.018
复制
发表时间：
2019-01-01
影响因子：
3.6
通讯作者：
Wang, Ji-Yang
中科院分区：
文献类型：
--
作者：
Lai, Nannan;Min, Qing;Wang, Ji-Yang
活化的T细胞表达的CD40配体（CD40 L）与B细胞上的CD40相互作用并触发B细胞存活、增殖和分化。由于T-B相互作用的缺陷（对于IG基因类别转换重组（CSR）至关重要），人类CD 40 L或CD 40的缺陷会导致高IgM综合征。CD40 L属于肿瘤坏死因子家族，通常在细胞表面形成同源三聚体，这对于其生物活性是重要的。为了产生可用于刺激小鼠和人B细胞的多聚体CD40 L，我们将已知也结合人CD40的小鼠CD40 L的胞外结构域与在生理条件下形成稳定四聚体的链霉亲和素（SA）融合。如预期的，用SA-CD40 L表达载体瞬时转染的293 T细胞在培养上清液中分泌四聚体SA-CD40 L。分泌的SA-CD40 L在诱导小鼠和人原代B细胞的存活、活化和增殖方面表现出比激动性抗小鼠或抗人CD40抗体强> 25倍的活性。在IL-4的存在下，SA-CD 40 L还在小鼠和人B细胞中诱导有效的CSR和浆细胞分化。此外，在小鼠中施用SA-CD 40 L诱导体内脾B细胞的活化和增殖。这些结果表明，在本研究中产生的SA-CD 40 L融合蛋白重现了膜结合三聚体CD 40 L的功能，并在小鼠和人原代B细胞中具有有效的生物学活性。
CD40 ligand (CD40 L) expressed by activated T cells interacts with CD40 on B cells and triggers B cell survival, proliferation and differentiation. Deficiency in CD40 L or CD40 in humans causes hyper IgM syndrome due to a defect in T-B interaction that is essential for Ig gene class switch recombination (CSR). CD40 L belongs to the tumor necrosis factor family and normally forms a homotrimer on the cell surface, which is important for its biological activity. To generate a multimeric CD40 L that can be used to stimulate both mouse and human B cells, we fused the extracellular domain of mouse CD40 L, which is known to also bind human CD40, with streptavidin (SA) that forms a stable tetramer under physiological conditions. As expected, 293 T cells transiently transfected with an SA-CD40 L expression vector secreted tetrameric SA-CD40 L in the culture supernatant. The secreted SA-CD40 L exhibited > 25-fold stronger activities in inducing the survival, activation and proliferation of both mouse and human primary B cells than did an agonistic anti-mouse or anti-human CD40 antibody. In the presence of IL-4, SA-CD40 L also induced efficient CSR and plasma cell differentiation in both mouse and human B cells. Moreover, administration of SA-CD40 L in mice induced activation and proliferation of spleen B cells in vivo. These results demonstrate that the SA-CD40 L fusion protein generated in the present study recapitulates the function of membrane-bound trimeric CD40 L and has potent biological activities in both mouse and human primary B cells.