Abstract:

 Objective     To investigate peripheral CD81 and CD4 expressions in patients infected by chronic Hepatitis C Virus (HCV),  and explore the modulation effect of CD81 on the immune system. Methods      Samples were collected from 55 chronic hepatitis C patients (infection group) and 25 healthy persons (control group). Peripheral expression of CD81 and CD4 were measured by flow cytometry. Serum level of IL2 and  HCV RNA were detected by ELISA and RTPCR, respectively. Results    The peripheral level of  CD81+ cells and the serum level of HCV RNA were positively correlated(r=0.474, P＜0.01) in the infection group. The numbers of the peripheral CD81+  lymphocytes and the CD3+CD4+ CD81+T cells among CD3+CD4+ T cells in the infection group were higher than those in the control group (P＜0.01). Both were positively correlated(r=0.581,P＜0.01). Also, the number of peripheral CD3+CD4+T cells and the serum level of IL2 in the infection group were considerably lower than those in the control group (P＜0.05). Both were also positively correlated(r=0.378, P＜0.05). Conclusion    After HCV infection, the consistent presence of HCV RNA can promote expression of CD81 while number of CD3+CD4+T cells and secretion of  IL-2 decline, which participate in the immuno-regulation of the patients.

Key words: Hepatitis C virus; Cluster of differentiation 81; CD3+CD4+T cells; Interleukin-2; Hepatitis C virus RNA