| Objective To investigate the role of Epstein-Barr virus(EBV) infection on the abnormal activation of B-lymphocyte in peripheral blood of Systemic Lupus erythematosus(SLE) patients,and the relationship between EBV infection and the abnormal activation of B-lymphocytes and SLE activity.Methods BamH I-W genome in EBV DNA of 52 SLE patients and 23 controls were examined by PCR-southern blotting.The level of ANA and EBV VCA-IgM in sera were examined with ELISA.The expression of CD19~+,CD23~+/CD19~+,CD21~+/CD19~+ and HLA-DR~+/CD19~+ were detected by flow cytometry.RESULT①The positive rate of BamH I-W fragment in SLE patient group and normal group is 61.54%and 30.44%respectively.There was significant difference in the positive rate between SLE patients group and the controls.The positive rate in SLE active phase and inactive phase is 65.62%and 70.00%respectively,both the difference of the positive rate between SLE active phase and the controls,and also between SLE inactive phase and the controls were significant.However,no significant difference was observed between SLE active and inactive phase(P＞0.05).②The expression rate of CD19~+,CD23~+/CD19~+ and HLA-DR~+/CD19~+ in SLE active phase was significantly higher than that of SLE inactive phase and the controls(P＜0.01),while the differences between SLE inactive phase and the controls were not significant(P＞0.05).There was positive relationship between the expression rate of CD23~+/CD19~+ and condition integral and the level of ANA(P＜0.01).On the other hand,no relationship was found between the expression rate of HLA-DR~+/CD19~+ and them(P＞0.05).③Both the expression rate of CD21~+/CD19~+ and CD23~+/CD21~+/CD19~+ were low in all the three groups.No difference was observed between each other(P＞0.05).④The expression rate of CD19~+ and CD23~+/CD19~+ in EBV-positive SLE patients was higher than tha of EBV-negative patients.The difference between them was significant(P＜0.05).But no difference was observed in the expression rate of CD21~+/CD19~+ between them(P＞0.05).Meanwhile,the fluorescence signal of CD21 and CD23 in B cell of EBV-positive SLE patients was stronger than that of EBV-negative ones.There was significant difference too(P＜0.01).⑤The EBV-VCA-IgM in 5 out of 52(9.62%) SLE patients was positive,and its level of the positive samples was 65.23 arbU/ml.Instead,it was negative in all the 23 controls.All of the 5 positive SLE patients were EBV-positive patients and also in SLE active phase.Furthermore,all of them were not newly diagnosed patients.Yet there was no significant difference between each other including the level of EBV IgM and the positive rate(P＞0.05).CONCLUSION①EBV infection may be related to the pathogenesis of SLE.It is also one of the environmental pathogenesis factors to SLE.②EBV infection may be related to the abnormally activation of B-lymphocytes.EBV may infect and activate B-lymphocytes by up regulating the expression of CD21 and CD23 of B-lymphocytes.③The abnormally activation of B-lymphocytes is associated with SLE activity directly. |
