Optimization,verification and application of ELISA method for quantitative detection of varicella-zoster virus IgG antibody / 中国生物制品学杂志

ABSTRACT

@#Objective To optimize and verify the ELISA method for quantitative detection of varicella-zoster virus(VZV)IgG antibody potency,and use it for the screening of plasma with high potency VZV-IgG in healthy donors.Methods The VZV-IgG indirect ELISA kit from Institut VirionSerion GmbH was selected,the first international standard for varicellazoster immunoglobulin(NIBSC codeW1044)was diluted to 2 IU/mL as the standard,and 4-parameter fitting curve was used to develop the quantitative ELISA method. The method was determined for the optimal linear range and verified for the precision and accuracy. VZV-IgG antibody potency of 1 962 human plasma samples and some batches of human immunoglobulin preparations from 10 plasma stations under Sinopharm Wuhan Plasma-derived Biotherapies Co.,Ltd.(SWPB)were detected by the developed method.Results The linear range of the standard curve was 16. 25 ～ 2 000 mIU/mL,the CV values of precision in intra-and inter-assays were 1. 3% ～ 10. 6% and 4. 270% ～ 7. 636%,and the accuracy in intra-and inter-assays were 92. 30% ～ 111. 02% and 98. 40% ～ 104. 88%,respectively;Sample-adding experiment showed that the measured value of the added sample was 95. 79% ～ 111. 03% of the theoretical value. The positive rate of 1 962 human plasma samples was 94. 29%,and the samples with potency greater than 3 000 mIU/mL accounted for 1. 02%. The potency of VZV-IgG antibody in different kinds of human immunoglobulin preparations was lower,while higher than that of intravenous human immunoglobulin(pH 4).Conclusion The optimized VZV-IgG quantitative detection method can be used for the screening of VZV-IgG in healthy people. The positive rate of VZV-IgG antibody in naturally infected healthy plasma donors is high,while the potency is low,thus,vaccine immunization is required to obtain qualified plasma with high potency.