[Effects of Kaempferol on Activation, Proliferation and Cell Cycle of Mouse T Lymphocytes in Vitro.]

Aim: To study the effects of Kaempferol on activation, proliferation and cell cycle of murine T lymphocytes, and to elucidate the mechanism of the immunosuppressive effect of Kaempferol.

Methods: Lymphocytes were prepared from lymphoid nodes of mouse, and were stimulated with polyclonal activators ConA, and then were co-cultured with Kaempferol of different final concentration. The effect on the expression of CD69 (the early marker of the activated T cells) on T lymphocytes were measured by flow cytometry combined with two colored monoclonal antibodies flow cytometry. While, the effect of Kaempferol on the proliferation of T lymphocytes in response to ConA stimulation was determined by MTT, cell cycle was detected by PI staining.

Results: Kaempferol (final concentration is 10, 20 and 40 mumol/L) can inhibit the expression of CD69 on activated T lymphocytes in a dose-dependent manner (P<0.05). The expression rate of CD69 on T cells in response to ConA was (39.11+/-1.17)%. After treatment with Kaempferol, the expression rate of CD69 reduced to (30.64+/-0.23)%, (27.95+/-0.04)% and (5.63+/-0.37)%, respectively (P< 0.05); The result of MTT showed that Kaempferol can inhibit the proliferation of T lymphocytes stimulated by ConA in a dose-dependent manner (P<0.05); The result of PI staining showed that Kaempferol can arrest cell cycle at S phage and G2/M at all experimental concentration (P<0.05).

Conclusion: Kaempferol can effectively inhibit the activation, proliferation of mouse T lymphocytes in respond to ConA, arrest cell cycle at S phage and G2/M in vitro.