[The effect of morin on activation, proliferation and cell-cycle of murine T lymphocytes in vitro].

Aim: To discover the effects of morin on the activation, proliferation and cell-cycle of murine T lymphocytes in vitro.

Methods: Murine lymph node-derived T lymphocytes were separated and stimulated with concanavalin A (ConA) and different experimental groups were set by co-cultured with morin of different final concentration. Flow cytometry (FCM) was used to detect the activation, proliferation [carboxylfluorescein diacetate, succinimide ester (CFDA-SE) staining] and cell-cycle [propidium iodide(PI) staining] of T cells.

Results: After 6 h time of culture in vitro, the rate of CD69(+) T cells in control group was (2.97+/-0.12)%, while it was significant higher in ConA group [(72.52+/-0.66)% (P<0.01)]. Morin could down-regulate this rate at final concentration being 25, 50 and 100 micromol/L, with a peak at 100 micromol/L morin [(48.95+/-0.81)% (P<0.01)]. CFDA-SE staining showed that at 48 h and 72 h, the proliferation indexes (PI) of T cells in ConA group were (1.58+/-0.04) and (1.95+/-0.02), respectively. Morin could significantly decrease the PI value at all experimental concentration, with the peak effect at 100 micromol/L morin, which the PI for 48 h was (1.02+/-0.02) and (1.03+/-0.01) for 72 h (P<0.01). FCM analysis of PI staining implied that the percentage of S phase cells in ConA group was (27.05+/-0.39)%, significantly higher than that in control group (5.10+/-0.07)%; and the 25 and 50 micromol/L morin groups showed higher S phase cell rates.

Conclusion: Morin can significantly inhibit ConA stimulated activation and proliferation of murine T lymphocytes, in which the S phase lagging may serve as one of the major mechanisms.