共刺激分子4-1BBL和B7-1对人T淋巴细胞的协同激发作用

The costimulatory effect of 4-1BBL and B7-1 molecules on human peripheral blood T lymphocyte

目的 :探讨 4 1BBL和B7 1这 2种共刺激分子在人外周血T淋巴细胞活化、增殖中的作用和机制。方法 :采用免疫磁珠阴性选择方法分离纯化人外周血T淋巴细胞 ;单向混合淋巴细胞反应 (MLR)分析共刺激分子对T细胞的激发作用 ;3H TdR掺入法测定细胞增殖 ;免疫荧光标记和流式细胞仪表型分析 ;ELISA检测细胞因子。结果 :经免疫磁珠阴性选择分离获外周血单个核细胞中的T细胞纯度 >90 %;人多发性骨髓瘤细胞株 (XG细胞 )转染 4 1BBL和B7 1cDNA后 ,细胞膜表面能稳定高表达这 2个分子 ,4 1BBL和B7 1转基因细胞也均能使同种异体T细胞发生活化、增殖、存活时间延长和介导细胞因子IL 2的分泌 ,且 2种共刺激分子具有一定的协同效应。结论 :4 1BBL和B7 1分子具有赋予XG细胞对T细胞的体外激发、促增殖和分泌IL 2的作用 ,4 1BBL和B7 1分子能产生协同效应。

Objective:To explore the role and mechanism of 4-1BBL and B7-1 molecules in the activation and proliferation of human peripheral blood T lymphocyte. Methods:T lymphocyte was purified by magnetic beads negative selecting. The proliferation of T cells in primary allogenic MLR was evaluated by using 3H-TdR incorporation; The immunophenotype of T cells was analyzed by FACS and the quantitative measurement of IL-2 in culture supernatant were performed by ELISA.Results:After negative selection, the purity of CD3+ T cells was over 90%; 4-1BBL and B7-1 molecules stably expressed on XG cells after 4-1BBL and B7-1 cDNA transfection; 4-1BBL or B7-1 gene transfected XG cells could more effectively mediate the activation, proliferation and IL-2 secretion of T cells than XG cells did, and the results also showed that the costimulatory molecules had a co-activating effect on T cells.Conclusion:Human multiple myeloma cells failed to induced antitumor immunoresponse because of the lack or weak expression of costimulatory molecules. The costimulatory molecules of 4-1BBL and B7-1 has a synthetic effect on endowing myeloma cells with enhancing the activation、proliferation and IL-2 secretion of T cells in vitro. [