Abstract: Objective To study the relationship between the apoptosis of lymphocytes and its significance in the pathogenesis of SLE.Methods Apoptosis was detected by Annexin V and flow cytometry(FCM),anti-ENA autoantibodies were detected with Western blot,and complement(C3)was tested quantitatively by turbidimetry.Results The percentage of the early apoptotic lymphocytes in the peripheral blood of active SLE patients was significantly higher than that of inactive SLE patients(P<0.001)and that of normal healthy controls(P<0.001),but there was no significant difference between quiescent SLE and normal healthy controls(P>0.05).Of the active SLE patients,no difference was found between those treated and not treated with corticosteroids or immunosuppressive agents(P>0.05).The percentage of apoptotic lymphocytes in those with more than two kinds of autoantibodies was markedly higher than those with only one kind of autoantibody(P<0.001)in SLE patitents.Besides,the rate of lymphocyte apoptosis was negatively correlated with serum complement C level in active SLE patients(r=-0.8587,P<0.01).Conclusion The increase of early apoptotic lymphocytes in the peripheral blood of SLE patients may contribute to the pathogenesis of SLE by producing excessive amount of autoantibodies.

Key words: Lupus erythematosus,systemic, Lymphocytes, Apoptosis