In the peripheral blood mononuclear cells (PBMCs) of HCV infected patients the expression of STAT1 and IRF-1 is downregulated while that of caspase-3 upregulated

Several peripheral blood mononuclear cell (PBM C) defects have been linked with hepatitis C virus (HCV) infection, including alterations in cytokine secretion and increased cell death. This study was performed to investigate the expression levels of signal transducer and activator of transcription 1 (STAT1), interferon regulatory factor 1 (IRF-1), and caspase 3 in PBMCs of patients infected with HCV. STAT1, IRF-1, and caspase 3 expression levels were compared in PBMCs from 19 untreated (naive) HCV+ patients, 8 treated (sustained responder [SR]) HCV patients, and 20 HCV-healthy controls. Moreover, PBMCs from naive HCV+ patients and SR-HCV patients were also evaluated for HCV RNA expression. The expression levels of STAT-1 and IRF-1 were significantly downregulated in PBMCs from naive HCV+ patients (P<0.04) and SR-HCV patients (P<0.05) compared to HCV-controls. In comparison with HCV-controls, naive HCV+ and SR-HCV patients showed a significant upregulation in the expression of caspase-3 in their PBMCs (P<0.0005 and P<0.03, respectively). No significant differences were observed in the expression of STAT-1, IRF-1, and caspase-3 between PBMCs from naive HCV+ and SR-HCV patients. HCV RNA was detected in PBMCs from 18 (94.7%) naive HCV+ patients as well as 6 (75%) SR-HCV patients. Downregulation of STAT1 and IRF-1 expression levels and upregulation of caspase-3 expression level in PBMCs from HCV-infected patients may contribute to alterations in cytokine secretion and enhanced PBMCs cell death reported in previous studies.