Rapid reduction of hepatitis C virus-Core protein in the peripheral blood improve the immunological response in chronic hepatitis C patients

Aim: The extracellular hepatitis C virus (HCV)-antigen, including HCV-Core protein, can suppress immune cells. Recently, the efficacy of double filtration plasmapheresis (DFPP) for chronic hepatitis C (CHC) was reported. However, the mechanism of efficacy of DFPP might not be only the reduction of HCV but also the effect of immune cells via direct and/or indirect mechanisms. The aim of this study is to analyze the virological and immunological parameters of difficult-to-treat HCV patients treated with DFPP combined with Peg-interferon and RBV (DFPP/Peg-IFN/RBV) therapy. Methods: Twelve CHC patients were enrolled and treated with DFPP/Peg-IFN/RBV therapy. The immunological, virological and genetic parameters were studied. Results: All patients (4/4) treated with the major IL28B allele (T/T) could achieve complete early virological response (EVR). The amounts of HCV-Core antigen in the peripheral blood of EVR patients treated with DFPP/Peg-IFN/RBV rapidly declined in comparison to those of late virological response (LVR) patients treated with DFPP/Peg-IFN/RBV and EVR patients treated with Peg-IFN and RBV (Peg-IFN/RBV). The amount of IFN-γ produced from peripheral blood gradually increased. On the other hand, the amount of IL10 gradually decreased in the EVR patients. The frequencies of HCV-Core binding on CD3+ T cells rapidly declined in EVR patients treated with DFPP/Peg-IFN/RBV therapy. Moreover, the distributions of activated CD4⁺and CD8⁺ T cells and CD16-CD56 high natural killer cells were significantly changed between before and after DFPP. Conclusions: The rapid reduction of HCV-Core antigens and changes in the distribution of lymphoid cells could contribute to the favorable immunological response during DFPP/Peg-IFN/RBV therapy.