滤泡树突状细胞对T细胞活化、凋亡相关分子及第二受体表达作用的研究

Effect of follicular dendritic cells to the expression of activation- and apoptosis-associated moleculers and coreceptors on T lymphocytes

目的:研究滤泡树突状细胞(Follicular dendritic cells,FDC)对T细胞活化、凋亡及受体表达的作用。方法:应用密度梯度离心法分离培养扁桃体FDC和外周血淋巴细胞,将FDC或FDC培养上清与淋巴细胞共培养5天,收集培养细胞,应用流式细胞术分析共培养后T细胞活化受体(CD38)、凋亡受体(CD95)及第二受体(CCR5、CXCR4)表达情况,用ELISA方法测定培养上清中TNF-α含量。结果:FDC和FDC培养上清能够显著增强CD4+T细胞表面活化标志CD38、第二受体CX-CR4的表达(P<0.05),并且能够显著抑制CD4+T淋巴细胞凋亡标志CD95的表达(P<0.05)。FDC和FDC培养上清能够促进T淋巴细胞分泌TNF-α(P<0.05)。结论:FDC可促进CD4+T淋巴细胞的活化和第二受体CXCR4的表达,抑制CD4+T细胞的凋亡,并且能够促进T细胞分泌TNF-α。

Objective:Effect of FDC on the expression of activation-,apoptosis-associated molecules and coreceptors of T lymphocytes were investigated.Methods:FDCs were isolated from tonsils freshly obtained from routine tonsillectomy and lymphocytes were isolated with density gradient centrifugation. Coculture of FDCs or the supernatant of FDCs with the lymphocytes were carried out for five days. The activation, apoptosis and the expression of coreceptors CCR5, CXCR4 on T lymphocytes were determined by flow cytometry. The content of TNF-α in the supernatant was determined by ELISA. Results:FDC and FDC culture supernatant could enhance the expression of the CD38 and CXCR4 on the CD4+T lymphocytes, and could enhance the production of TNF-α by T lymphocytes(P<0.05). Moreover, it could inhibit the expression of CD95 on the CD4+T lymphocytes (P<0.05). FDC and FDC culture supernatant could enhance the secretion of the TNF-α by T cells.Conclusion:FDCs may promote the activation and CXCR4 expression in CD4+T lymphocytes, and inhibit apoptosis of CD4+T lymphocytes.They can also promote T lymphocytes to secrete TNF-α.