Lymphocyte apoptosis and P53 expression in peripheral blood lymphocytes of patients with systemic lupus erythematosus stimulated by IL-18

Objective To study the change of lymphocyte apoptosis and P53 protein in the peripheral blood of SLE patients. Methods Apoptosis and P53 protein in lymphocyte were investigated in 44 SLE patients and 30 normal people by using annexin V united PI staining method and immunofluorescence staining method. Results The percentage of lymphocyte apoptosis from active SLE was significantly higher than that of normal control ( P 0.01). No significant difference of apoptosis was found in active SLE as compared with control ( P 0.05). Expression of P53 protein in lymphocyte from active SLE was significantly lower than that of control ( P 0.01). No significant diffe rence in the expression of P53 protein was found in active SLE as compared with that of control ( P 0.05). Expression of P53 protein in lymphocyte from SLE patients showed high correlation with SLEDAI, dsDNA and C3 ( P 0.01). Conclusion The percentage of PBMC apoptosis from active SLE patients stimulated by IL 18 was increased, suggesting that IL 18 could influence the apoptosis in vivo and immune mechanism of apoptosis.