[Effects of MSC on Cell Cycle, Phenotype and Cytokine Secretion of T Cells Activated by PHA]

Aim: To study the effect of human bone marrow derived mesenchymal stem cell (MSC) on T cell cycle and activation, and to investigate the inhibitory effect of MSC on T cell proliferation and the underlying mechanism.

Methods: Human bone marrow derived MSC were isolated by gradient centrifugation. then in vitro MSC were cultured, expanded,and were used in test after third passage. FCM analysis and ELISA were used to investigate the effects of MSC on the early activation marker expression of T cells, cell cycle and cytokine secretion.

Results: T cells stimulated by PHA in the presence of MSC were arrested at G0/G1 phase. The expression of the early activation marker CD25 and CD69 of T cells was inhibited in the presence of MSC both in CD4(+) and CD8(+) T cell subpopulation. MSC caused a sharp decrease of cytokine secretion in IL-2 and IFN-gamma.

Conclusion: Human bone marrow derived MSC can suppress the activation and proliferation of T cells by altering T cell cycle.