蛋白激酶Cθ信号途径在结核分枝杆菌抗原激活人γδT细胞增殖和分化中的作用

目的 研究蛋白激酶Cθ(protein kinase Cθ,PKCθ)信号途径在结核分枝杆菌抗原(Mycobacterium tuberculosis antigen,Mtb-Ag)激活人γδT细胞增殖和分化中的作用.方法 健康人外周血单个核细胞(PBMC)用Mtb-Ag和IL-2优势刺激和扩增γδT细胞,或预先用5.0μmol/L Rottlerin(楸毒素)预处理,培养不同时间后,用流式细胞术(FCM)检测γδT细胞表面活化分子和细胞因子表达;同时采用活体染料羧基荧光素乙酰乙酸(CFSE)标记细胞,流式细胞术分析Mtb-Ag刺激γδT细胞后的增殖和各子代细胞百分率.结果 PBMC经Mtb-Ag刺激后3d,γδT细胞CD69和CD25表达分别为46.2%和45.6%,而Rotderin预处理显著地抑制了CD69和CD25表达(P＜0.01);PBMC经Mtb-Ag激活培养5、10和15d,培养扩增细胞中的γδT细胞比例分别为9.6%、54.6%和82.4%,其中第5天已有少部分γδT细胞发生增殖,第10天和第15天时几乎全部γδT细胞分裂都在6代以上,用Rottlerin预处理,显著抑制了γδT细胞增殖反应,但在培养第10天后仍有少部分γδT细胞发生增殖反应;同时在培养第7天、14天和21天,用PMA(佛波酯)+Ionomycin(离子霉素)再刺激后,产生IFN-γ的γδT细胞均在80%左右;培养21d时,有2.6%的γδT细胞表达IL-4.在Rottlerin预处理组产生TH1型细胞因子IFN-γ的γδT细胞均显著减少(P＜0.05),而γδT细胞表达TH2型细胞因子IL-4则几乎完全抑制(P＜0.01).结论 PKCθ信号途径在Mtb-Ag刺激γδT细胞的增殖和分化中均起重要作用.

The roles of PKCO signaling pathway in the proliferation and differentiation of the γδT lymphocytes stimulated by Mycobacterium tuberculosis antigen

Objective To explore the roles of PKCθ(protein kinase Cθ)signaling pathway on the activation,proliferation and TH1/TH2 cytokines production of the γδT lymphocytes stimulated by Mycobacterium tuberculosis antigen(Mtb-Ag) in vitro.Methods Peripheral blood mononuclear cells(PBMC)were pretreated with or without Rottlerin at 5.0 μmol/L,and stimulated with Mtb-Ag and cultured in rhIL-2 containing medium.After different time of culture,activation molecules and cytokines production of γδT cells were measured by flow cytometry.The proliferation proportion and the percentage of each generation of γδT cells were determined by carboxylfluoreseein diacetate succinmidyl ester(CFSE)labeling technique and flow cytometry.Results After 3d of stimulation with Mtb-Ag,the expression rates of CD69 and CD25 of γδT cells were 46.2%and 45.6%,respectively.Pretreatment of 5.0 μmol/L Rottlerin markedly inhibited the both expressions of CD69 and CD25 in γδT cells(P＜0.01).After stimulation and expansion in vitro for 5,10,and 15 d,the percentages of the γδT cell were 9.6%,54.6%and 82.4%,respectively.There was a few γδT cells in propagation on the 5th day of culture,and almost all γδT cell divisions were above 6 generations on the 10th and 15th day of culture.Pretreatment of the Rotflerin significantly suppressed the γδT cell proliferation,but after 10 d culture,there were still a few parts of γδT cells in propagation.Meanwhile,after 7,14,and 21d of culture,upon stimulation with PMA+Ionomycin,the IFN-γ producing-γδT cells were about 80%at all times.But only after 21d culture,IL-4-producing γδT cells was 2.6%.,The percentage of IFN-γ producing γδT cells markedly reduced in Rottlerin group(P＜0.01).IL-4 secretion of the γδT cells was almost completely blocked.Conclusion PKCO signal pathway involves in activation,proliferation and differentiation of the γδT lymphocytes stimulated by Mtb-Ag.