The Ras/Erk pathway in the specially activated human ??T cells by Mycobacterium tuberculosis low molecular peptide antigen / 中国免疫学杂志

ABSTRACT

Objective:To investigate involvement of the Ras/Erk signal pathway in activation of human ??T cells stimulated by Mycobacterium tuberculosis low molecular peptide antigen(Mtb-Ag).Methods:PBMC were isolated from peripheral blood of healthy subjects and simulated in vitro with Mtb-Ag,CD3mAb or PMA and inomysin(IM).CD69 expression of total T cells and ??T cells were measured by flow cytometry at different hours after stimulation, and the number of expanded ??T cells were counted after 10 days of culture. PD98059,a specific inhibitor for Erk pathway was used to treat PBMC for 30 min before stimulation.Results:The proportions of CD69 expressing cells in total T cells and ??T cells were same as 99% at 6 h after stimulation of PBMC with PMA +IM and similar about 55% at 24 h after stimulation with CD3 mAb,whereas those at 24 h stimulation of PBMC with Mtb-Ag were 75.2% and 16.0%,respectively.CD69 expression and proliferation of ??T cells activated by Mtb-Ag were markedly inhibited by pretreatment of PBMC with PD98059.Conclusion:Mtb-Ag is a specific stimulator for activation of ??T cells, and Ras/Erk signal transduction pathway involves in the activation of ??T cells.