ESTABLISHMENT AND CHARACTERIZATION OF NS3 PROTEIN-SPECIFIC T-CELL CLONES FROM A PATIENT WITH CHRONIC HEPATITIS-C

Our previous study showed dominant proliferative response of periphera l mononuclear cells to hepatitis C virus (HCV) nonstructural (NS-3) (T 9, from aa 1188 to 1493) in chronically infected patients. Six T9-spec ific T-cell clones derived in an HCV patient were established and stud ied for the antigen specificity and the ability of augmentation of in vitro antibody production. All these cloned T-cell lines responded exc lusively to T9 antigen and could help autologous B cells in producing anti-T9 antibody in vitro. Cytokine mRNAs of these T cells was detecte d by polymerase chain reaction and predominant IL-2 and IFN-gamma prod uction was noted. In addition, further elucidation of T-cell antigenic determinant and MHC restriction suggested that these T-cell clones re cognized at least two different T-cell antigenic determinants within t he NS-3 region in an HLA DQ2-restricted manner. We believe characteriz ation of HCV-specific T-cell responses, especially T-cell epitope mapp ing and cytokine production pattern, may shed light on further underst anding the pathogenic mechanism and designing therapy for HCV infectio n.