摘要
目的:探讨在体外条件下负载灭活口蹄疫病毒(FMDV)树突状细胞活化CD8+T细胞的机制。方法:用重组粒细胞-巨噬细胞集落刺激因子(rmGM-CSF)和白介素-4(rmIL-4)将小鼠外周血单核细胞诱导分化成树突状细胞(MoDCs),以信号阻断法从淋巴结T细胞制备CD8+T细胞,利用负载灭活FMDV的MoDCs与CD8+T细胞共培养,以FMDV+MoDCs+淋巴结T细胞作为对照,用ELISA检测不同时间培养上清液中IFN-γ的含量。用蛋白酶体抑制剂和溶酶体抑制剂处理MoDCs,2小时后再负载灭活FMDV,并与CD8+T细胞共培养,对照组则用FMDV+MoDCs+CD8+T细胞和FMDV+MoDCs,用ELISA检测不同时间培养上清液中IFN-γ的含量。结果:在共培养9小时,CD8+T细胞的IFN-γ释放量约为淋巴结T细胞IFN-γ释放量的1/6,随后,淋巴结T细胞和CD8+T细胞均产生少量IFN-γ。用灭活FMDV负载被lactacystin和氯喹处理的DCs与CD8+T细胞共培养后9~12小时,CD8+T细胞产生IFN-γ显著减少,在共培养24小时,IFN-γ释放显著增多,并在36小时达到峰值,与对照组相比,差异有统计学意义。结论:负载灭活FMDV的MoDCs可以活化淋巴结T细胞,而且,还可通过非MHCⅠ和非MHCⅡ类分子依赖途径激活CD8+T细胞,此即旁位活化效应。
Objective:To study the mechanism of CD8 ^ + T cell activation by dendritic cells loaded with inactivated FMDV in vitro. Methods: Monocyte-derived dendritic cells(MoDCs) were generated from peripheral blood monoytes by adding to rmGM-CSF and rmIL-4 in the medium. CD8^+ T cells were produced by depletion of CD4^ + T cells with appropriate antibody in the lymph node T cells. MoDCs pulsed with inactivated FMDV were co-cultured with CD8^+ T cells. Inactivated FMDV pulsed-MoDCs were cocultured with lymph node T cells as control. The production of the IFN-γ was determined at different time points with ELISA. The MoDCs were incubated with proteasome inhibitor and lysosome inhibitor for 2 h and then pulsed with inactivated FMDV and co-cultured with CD8^+ T cells. Inactivated FMDV pulsed-MoDCs alone in culture was utilized as control.The production of the IFN-γ was determined at different time points by using ELISA. Results:At 9h post-co cuhuration, the level of IFN-γ in supematant of lymph node cell culture was approximately six fold higher than that of CD8 ^+ T cells in culture medium. Subsequently, small amount of IFN-γ produced by the 1)anph node T cells and CD8^ + T cells was determined, respectively. The inhibitor group's level of IFN-γ was remarkably reduced from 9 h through 12 h. By contrast, the quantity of IFN-γ produced was significantly higher in inhibitor group compared to the control groups at 24 h post-co cuhuration. And the level of IFN-γ in inhibitor group reached peak at 36 h post-co culturation in comparison with the control groups. Conclusion: MoDCs loaded with inactivated FMDV have the capability of initiating T cell response. Furthermore, inactivated FMDV pulsed MoDCs can activated naive CD8^+ T cells independently of both MHC Ⅰ and MHC Ⅱ molecule pathways, which is known as bystander activation.
出处
《中国免疫学杂志》
CAS
CSCD
北大核心
2009年第8期721-726,共6页
Chinese Journal of Immunology
关键词
树突状细胞
口蹄疫病毒
抗原提呈
旁位活化
Dendritic cell
Foot-and-mouth disease virus
Antigen presentation
Bystander activation