Role of p38 and phosphatidylinositol 3 kinase(PI3K) in the signal transduction of apoptosis of activated human ??T cells induced by restimulating with Mycobacterium Tuberculosis antigen / 中国免疫学杂志

ABSTRACT

Objective:To establish the model of apoptosis of activated human ??T cells induced by restimulating with Mycobacterium tuberculosis antigen(Mtb-Ag). To investigate the roles of p38 and phosphatidylinositol 3 kinase(PI3K) pathways in the apoptosis of activated human ??T cells induced by restimualting wih Mtb-Ag.Methods:Mtb-Ag activated human T cells(MtbAT) were cultured for 15 days to 25 days and restimulated with three concentrations of Mtb-Ag for 24 hours, and the apoptosis of ??T cells were measured by flowcytometry(FCM) using Annexin-V-FITC/PI staining. Mtb-AT were restimulating with Mtb-Ag(10 ?g/ml) for 3, 6, 12 and 24 hours, the apoptosis of ??T cells were detected. Mtb-AT cells were pretreated with SB203580(an inhibitor for p38 pathway), or LY294002(an inhibitor for PI3K pathway) for 60 minutes, and restimulating with Mtb-Ag for 3 hours, the apoptosis of ??T cells were detected.Results:Both 10.0 and 20.0 ?g/ml Mtb-Ag significantly induced the apoptosis of ??T cells(P0.05). Compared with control, the apoptosis of ??T cells could be significantly induced by restimulating MtbAT with Mtb-Ag(10.0 ?g/ml) for 3, 6, 12 and 24 hours(P0.05) in the percentages of apoptosis of ??T cells restimulated by Mtb-Ag(10.0 ?g/ml) between for 3 hours and for 24 hours, the percentages of apoptosis of the latter is higher than the former about 7.55%. The apoptosis of ??T cells induced by restimualting wih Mtb-Ag could be inhibited by SB203580(80.0 ?mol/L) or LY294002(10.0 ?mol/L), the inhibition rate of apoptosis was 91.6% and 43.1%, respectively.Conclusion:We established the model of apoptosis of activated human ??T cells by means of using Mtb-Ag(10.0 ?g/ml) to restimulate activated ??T cells for 3 hours. The test of inhibitors of signalling molecule suggested the signalling pathways including p38 and PI3K, participated in the apoptosis of activated human ??T cells restimulated by Mtb-Ag.