Cytokine Profiles and Cell Proliferation Responses to Truncated ORF2 Protein in Iranian Patients Recovered from Hepatitis E Infection
Background.The aim of this study was to evaluatehepatitis E virus(HEV) specific cellular immune responses to truncated ORF2 protein in Iranian patients recovered from HEV infection. Information about HEV-specific immune responses could be useful in finding an effective way for development of HEV vaccine.Methods.A truncated form of HEV ORF2 protein containing amino acids 112-608 was used to stimulate peripheral blood mononuclear cells (PBMCs) separated from HEV-recovered and control groups. Finally, the levels of four cytokines, IFN-γELISPOT, and cell proliferative responses following stimulation with the truncated ORF2 protein were assessed in the both groups.Results.The truncated ORF2 protein was able to induce IFN-γELISPOT and cell proliferation responses and to produce significant amounts of IFN-γand IL-12 cytokines, but low amounts of IL-10 and IL-4 cytokinesin vitro. These responses were significantly higher in the recovered group compared to the control group. These results indicate the antigenic nature of the truncated ORF2 protein and production of T helper type 1 cytokines.Conclusion.The truncated ORF2 protein can effectively induce significant cellular immune responsesand can be introduced as a potential vaccine candidate. However, further studies are required to evaluate this proteinin vivo.