Effect of an extracellular signal regulated kinase 1/2 signal pathway on proliferation,cell cycle and activation of mouse lymphocytes

Aim:To investigate extracellular signal regulated kinase 1/2(ERK1/2) signal pathway on proliferation,cell cycle and activation of mouse lymphocytes. Methods:Lymphocytes were isolated from lymph nodes in BALB/c mice and then stimulated with polyclonal activators,concanavalin(ConA) and phorbol12,13-dibutyrate(PDB) plus ionomycin(Ion).The proliferation,cell cycle and activation of T lymphocytes were analyzed using flow cytometry(FCM).Results:Carboxy fluoresce in diacetate succinimidyl ester(CFDA-SE) staining showed that 5,10,20,30 and 40 μmol/L PD98059 could significantly inhibit the proliferation of mouse T lymphocytes induced by ConA.The inhibitory effect appeared dose-dependent(r=0.985,P0.01).The analysis of the cell cycle induced by ConA revealed that the cells were blocked to enter S and G2/M phases with the concentration of PD98059 increased.PD98059 had the similar effect on the cells treated with PDB plus Ion,but the changes of S phase and G2/M phase were more distinct.The fluorescence-conjugated mAb staining showed that PD98059 had only slight inhibition of the expression of CD69 on the surface of T lymphocytes and had no effect on the expression of CD25 on the surface of T lymphocytes.Conclusion:PD98059 can inhibit the proliferation of the mouse T lymphocytes and block them to enter S and G2/M phases,but it can not remarkably inhibit the activation of mouse T lymphocytes induced by ConA.