Role Of Accessory Signals In The Activation Human Peripheral Blood γδT Cells By Mycobacterium Tuberculosis Low Molecular Peptide In Vitro

Objective To construct a method of expanding y8T cells from human peripheral blood in vitro and to investigate the role of antigen presenting cells in the activating human peripheral blood y8+T cells by low molecular peptide of Mycobacterium tuberculosis (Mtb). Methods The peripheral blood mononuclear cells (PBMCs) of healthy donors were stimulated by Mtb antigen in vitro and the activated y5T cells were expended in IL-2 contained medium. Monocytes and T cells were isolated from PBMCs by plastic adhesion and nylon column filtration. And then cultured according to following 3 combination form T cells only, T cells + monocytes and T cells +B cells. After stimulation of Mtb low molecular peptide, the proliferation of y6+T cells were analysed by flow cytometry. Results The yS+T cells were expanded 30 to 50-fold after 11 days stimulated by Mtb-Ag. The activation of human y5+T cells by Mtb antigen needed the existence of monocytes or B cells, but independed on their processing and presenting to Mtb antigen. Conclusion The Mtb low molecular peptide can activate preferentially y6+T cells of human peripheral blood PBMCs. The accessory cells are required for activation of y8T cells and it possess a special antigen recognition mechanism.