A major costimulatory molecule on antigen-presenting cells, CTLA4 ligand A, is distinct from B7.
A major costimulatory molecule on antigen-presenting cells, CTLA4 ligand A, is distinct from B7.
复制标题
DOI：
10.1084/jem.178.5.1789
复制
发表时间：
1993-11-01
期刊：
影响因子：
--
通讯作者：
Liu Y
中科院分区：
文献类型：
--
作者：
Wu Y;Guo Y;Liu Y
CTLA 4配体是重要的共刺激分子，因为可溶性CTLA 4Ig阻断T细胞应答的诱导并诱导T细胞耐受。由于当B7在成纤维细胞上表达时，CTLA 4免疫球蛋白（CTLA 4Ig）结合B7，因此广泛认为CTLA 4Ig通过阻断B7的功能来阻断T细胞共刺激。在这里，我们表明，主要的共刺激配体结合的CTLA4 Ig（我们的术语CTLA4配体A）的抗原呈递细胞不是由B7基因编码。CTLA4配体A在细胞分布和各自的表达水平方面也不同于B7。B7和CTLA4配体A两者都关键地参与T细胞共刺激。
CTLA4 ligands are important costimulatory molecules because soluble CTLA4Ig blocks the induction of T cell responses and induces T cell tolerance. As CTLA4 immunoglobulin (CTLA4Ig) binds B7 when the latter is expressed on fibroblasts, it was widely assumed that CTLA4Ig blocks T cell costimulation by blocking the function of B7. Here we show that the major costimulatory ligand bound by CTLA4Ig (which we term CTLA4 ligand A) on antigen-presenting cells are not encoded by the B7 gene. CTLA4 ligand A also differs from B7 in cellular distribution and in the respective levels of expression. Both B7 and CTLA4 ligand A are critically involved in T cell costimulation.