Double-antigen sandwich ELISA for detection of total antibodies against hepatitis C virus / 临床检验杂志

ABSTRACT

Objective To establish a double-antigen sandwich ELISA(S-ELISA) for detection of total antibodies against hepatitis C virus(HCV).Methods Recombinant HCV proteins fusion-expressed with His-tag and GST-tag were separately used as coating and HRP-labeling antigen of the S-ELISA.Serum samples were tested with both the S-ELISA and another commercial indirect ELISA(I-ELISA) kit(Beijing Wantai Biological Pharmacy Enterprise Co.Ltd.).HCV RNA in some of the samples were tested by RT-nested PCR.Results Among 1 968 tested samples,190(9.7%) were total anti-HCV-positive while 1 761(89.5%) were negative by both of the S-ELISA and I-ELISA,with a resultant concordance rate of 99.1% of the two ELISA assays.However,the results of 17(0.9%) were not consistent in the two assays,in which 14 were S-ELISA negative but I-ELISA positive and 3 were S-ELISA positive but I-ELISA negative.One of the 14 samples(0.7%) with S-ELISA negative was detected as HCV RNA-positive,while 2 of the 3(66.7%) samples with S-ELISA positive were detected as HCV RNA-positive.In addition,HCV RNA was detectable in 23 of 31(74.19%) samples which were total anti-HCV positive in both S-ELISA and I-ELISA.Taking the PCR data together into account,the sensitivity of the S-ELISA and I-ELISA were 99.48% and 98.96% and specificity were 99.94% and 99.27%,respectively.Conclusions The established S-ELISA in this study may provide a novel means for detection of HCV antibody with high sensitivity and specificity.