Significance of Two NS3 Recombinant Antigens Derived from Different Genotypes on Serological Diagnosis in Patients Infected with HCV

OBJECTIVE To explore the immunoreactivity of two NS3 recombinant antigens derived from different genotypes and to evaluate the application of the antigens on the serological diagnosis in patients infected with HCV.METHODS Two HCV NS3 recombinant antigens derived from HCV genotype 1 and 6 were applied in anti-HCV ELISA detection,respectively.The known anti-HCV-positive specimens and normal adult sera were tested with mixture of the two antigens.RT-nPCR based on universal primers for multiple HCV genotypes was used to detect HCV RNA.Data analysis was done by chi-square test.RESULTS 52 positive serum samples were detected out using the NS3 antigen from HCV genotype 1 and 50 samples detected out using the antigen from genotype 6,respectively,among 85 known anti-HCV-positive specimens.No difference between the two positive rates of anti-NS3 were found(χ2=0.06,P0.05).No antigenicity was found in 100 serum samples obtained from normal adult blood donors by both the two NS3 antigens.Sixty-five of 90 patient specimens were immunoreactive to the mixed antigens and the positive rate was 72.2%.Twenty-nine of 51 patient samples were RT-nPCR positive.CONCLUSION It shows different immunoreactivity of HCV NS3 antigens between HCV genotype 1 and 6.It may be a more better choice to apply the mixture of NS3 antigens from HCV different genotypes in the serological diagnosis in patients infected with HCV.