负载灭活口蹄疫病毒树突状细胞启动的CD8~＋T细胞应答

探讨在体外条件下负载灭活口蹄疫病毒（iFMDV）树突状细胞对CD8＋T细胞的活化效应。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）,用信号阻断法从淋巴结T细胞制备CD8＋T细胞,利用负载iFMDV的MoDCs与CD8＋T细胞共培养,以iFMDV＋MoDCs作为对照,用ELISA检测不同时间培养上清液中IFN-γ的含量。用蛋白酶体抑制剂处理MoDCs,2h后再负载iFMDV,并与CD8＋T细胞共培养,对照组则用iFMDV＋MoDCs＋CD8＋T细胞,用ELISA检测不同时间培养上清液中IFN-γ的含量。结果表明,同对照组相比,在共培养后9,12,24,36,48h,CD8＋T细胞组均产生高水平的IFN-γ。而且,经抑制剂预处理的MoDCs与CD8＋T细胞共培养后,其分泌的IFN-γ量不仅没有降低,反而显著升高。因此得出,MoDCs可与蛋白酶体等加工iFMDV抗原,并通过交叉提呈途径激活CD8＋T细胞。

CD8+ T lymphocyte response triggered by dendritic cells pulsed with inactivated foot-and-mouth disease virus

To explore the activation of CD8+T cell by dendritic cells pulsed with inactivated foot-and-mouth disease virus(iFMDV) in vitro,monocyte-derived dendritic cells(MoDCs) were generated by culturing peripheral blood monoytes with addition of rmGM-CSF and rmIL-4 in the medium.CD8+T cells were prepared by blocking of CD4+T cells with anti-CD4 antibody in the lymph node T cell pool.MoDCs pulsed with iFMDV were co-cultured with CD8+T cells.iFMDV pulsed-MoDCs were used as control.The release of IFN-γ was determined at indicated timepoints with ELISA.The MoDCs were treated with proteasome inhibitor for 2 h and pulsed with iFMDV for co-culture with CD8+T cells.iFMDV pulsed-MoDCs co-cultured with CD8+T cells was utilized as control.The level of IFN-γ in supernatant was determined at indicated timepoints by using ELISA.The levels of IFN-γ in supernatant of CD8+T cell culture were higher than those of the control at 9 h,12 h,24 h,36 h,and 48 h post co-culture.The levels of IFN-γ released from CD8+T cells triggered by iFMDV-pulsed MoDCs treated with lactacystin were higher than those of control group.These findings show that MoDCs have a capability of processing iFMDV in proteasome and other unidentified enzyme-containing compartments and corss-presenting antigenic peptides to CD8+T cells.