REDUCED ANTIBODY REACTIVITY TO HEPATITIS-C VIRUS-ANTIGENS IN HEMODIALYSIS-PATIENTS COINFECTED WITH HEPATITIS-B VIRUS

Antibody reactivities to hepatitis C virus (HCV) antigens and to synth etic peptides derived from different parts of the HCV genome (core, NS 4, and NS5) were evaluated in HCV-infected hemodialysis patients, In t he RIBA 3 assay, NS5 was significantly less recognizable by sera of he modialysis patients compared to other HCV-infected subjects, Among hem odialysis patients, those coinfected with hepatitis B virus (HBV) (pos itive for hepatitis B surface antigen [HBsAg(+)]) showed a reduction i n reactivity to C33 and C100, Sera of only 23% of the hemodialysis pat ients (37 of 161) reacted with more than three of eight peptides teste d, significantly fewer than the 60% (12 of 20) of the sera of other HC V-infected patients tested (P = 0.001), This immunosuppression was als o manifested by a reduced frequency of recognition of additional pepti des on follow-up, An even more reduced reactivity was observed among t he HBV-coinfected patients (HBsAg(+)). The low-responder hemodialysis patients were not infected with any particular genotype of HCV, and th e same HCV genotypes observed in the whole group of hemodialysis patie nts (la, Ib, 2a, and 3a) were found circulating in the low-responder g roup, Even in this low-responder population, the good performance of t wo peptides (peptide 716, corresponding to a portion of the core, and peptide 59, corresponding to a portion of NS4) corroborates the immuno dominance of the conserved epitopes within these peptides.