Objective:To study the apoptosis of T lymphocyte subsets of peripheral blood in systemic lupus erythematosus(SLE) and the correlated pathogenesis.Methods:The percentages of T lymphocyte subsets,the positive expression rates of Fas/FasL on T lymphocyte subsets,and the apoptosis of T lymphocyte subsets were determined by three-colorflow cytometry.The level of serum IL-10 was analyzed by ABC-ELISA.IL-10 antibody and FasL antibody were added respectively into the 48 hours' culture of 10 SLE patients' PBMCs in vitro,whose serum IL-10 significantly increased,and then,the changes of T lymphocyte subsets of SLE PBMCs were determined by three-colorflow cytometry.Results:1) In SLE,mainly in hyperactive SLE,the apoptosis of CD4+ T lymphocytes increased significantly(P

Objective: To study the apoptosis of T lymphocyte subsets of peripheral blood in systemic lupus erythematosus(SLE)and the correlated pathogenesis.Methods: The percentages of T lymphocyte subsets,the positive expression rates of Fas/FasL on T lymphocyte subsets,and the apoptosis of T lymphocyte subsets were determined by three-colorflow cytometry.The level of serum IL-10 was analyzed by ABCELISA.IL-10 antibody and FasL antibody were added respectively into the 48 hours' culture of 10 SLE patients' PBMCs in vitro,whose serum IL-10 significantly increased, and then, the changes of T lymphocyte subsets of SLE PBMCs were determined by three-colodlow cytometry.Results: 1)In SLE, mainly in hyperactive SLE, the apoptesis of CD4~+ T lymphocytes increased significantly(P＜0.05),and the ratio of CD4~+/CD8~+ decreased compared with normal controls,and the abnormal apoptesis of CD4~+ T lymphocytes had a positive correlation with the increased expression rates of Fas/FasL on CD4~+ and CD8~+ T lymphocytes(P＜0.05).2)The serum IL-10 level increased significantly in SLE (P＜0.01), expecially in hyperactive SLE, and serum IL-10 had a positive correlation with the level of serum anti-dsDNA antibodies, CD4~+/CD8 + ratio, and the positive expression rate of FasL on CD4 * T lymphocytes(P＜0.05).3)According to a tracking experiment on two different groups of SLE patients,we found that:with the stabilization of the illness,the level of serum IL-10 decreased significantly, the positive expression rate of Fas/FasL on T lymphocytes,particularly on CD4~+ T lymphocytes, reduced evidently,and the apoptosis of CD4~+ T lymphocytes decreased(P＜0.05).Conclusion: The abnormal activities of T lymphocytes, particularly of CD4~+ T lymphocytes from patients with SLE,which lead to AICD,cause the percentage of CD4~+ T lymphocytes and the ratio of CD4~+/CD8~+ to decrease,disorder immune response, and accelerate the process of SLE.As a key factor in modulating the positive expression rate of Fas/FasL on CD4~+ T lymphocytes,IL-10 plays an important role in causing SLE.