GENOTYPE DEPENDENCE OF HEPATITIS-C VIRUS-ANTIBODIES DETECTABLE BY THE1ST-GENERATION ENZYME-LINKED-IMMUNOSORBENT-ASSAY WITH C100-3 PROTEIN

Hepatitis C virus (HCV) samples in 155 sera, from patients with chroni c non-A, non-B liver disease and blood donors, were grouped into four genotypes (I, II, III, and IV) by amplification of core-gene sequences by polymerase chain reaction with type-specific primers. HCV genotype s were compared with various HCV-associated antibodies detectable by t he first-generation ELISA (ELISA-1) with C100-3 protein and a second-g eneration immunoblot assay with four recombinant HCV proteins. Antibod ies to C100-3 protein and those to its subsequence (5-1-1) were detect ed in 13 (93%) and 12 (86%), respectively, of 14 sera with genotype I HCV; 56 (79%) and 58 (82%) of 71 sera with genotype II; 13 (34%) and 6 (16%) of 38 sera with genotype III; and II (34%) and 4 (13%) of 32 se ra with genotype IV. Amino acid sequences of C100-3 of genotype I HCV are conserved by approximately 90% in genotype II, but only by approxi mately 75% in genotypes III and IV. The sensitivity of ELISA-1, theref ore, would be influenced by heterogeneity in C100-3 sequences of diffe rent genotypes.