ABSTRACT
Objective:To explore the role of CD28 in the activation of human peripheral blood ?? +T cells by Mycobacterium tuberculosis (Mtb) low molecular peptide antigen in vitro Methods:Mtb antigen and anti CD28 monoclonal antibody (mAb) were used as signal 2 to stimulate the r? + T cell from PBMC the expression of CD28 molecule on ?? +T cells, proliferation rate of ?? +T cells and expression of CD69 molecule on activated ?? +T cells were analyzed by using flow cytometry Results:CD28 molecule was expressed on 50% of ?? +T cells Neither Anti CD28 nor Mtb antigen alone, but both presence, could stimulate ?? +T cells activation and proliferation CD69 molecule was expressed on activated ?? + T cells.Conclusion:The CD28 molecule could provide the costimulatory signal in the full activation of ?? +T cells by Mtb low molecular peptide antigen CD69 molecule was also an early activation marker of ?? +T cells