两种商品化新型冠状病毒中和抗体检测试剂盒的应用性能评价

Evaluation of the performance of two commercial SARS-CoV-2 neutralizing antibody test kits

目的评价两种商品化新型冠状病毒(severe acute respiratory syndrome coronavirus 2,SARS-CoV-2)中和抗体检测EIA试剂盒的应用性能。方法使用两种商品化SARS-CoV-2中和抗体ELISA检测试剂盒(A和B),以疫苗免疫前血清44例、免疫后1个月血清120例、COVID-19患者愈后6个月的恢复期血清64例作为样本盘,进行中和抗体检测,同时通过活病毒微量中和试验(micro-neutralization test,micro-NT)检测上述血清样本的50%中和抗体滴度(50%neutralization titer,NT50)。分析两种商品化试剂盒与活病毒中和试验在定性及定量结果上的一致性。结果定性结果分析发现,以micro-NT检测结果作为标准,A和B试剂盒的阳性符合率分别为97.40%和100.00%;阴性符合率分别为97.30%和95.95%;约登指数分别为0.95和0.96。定量结果分析发现,对于疫苗免疫后样本,A、B试剂盒与micro-NT检测结果的相关系数分别为0.24(P<0.05)和0.52(P<0.0001);对于恢复期血清样本,A、B试剂盒与micro-NT检测结果相关系数分别为0.81(P<0.0001)和0.89(P<0.0001)。结论A和B两种商品化中和抗体检测试剂盒与micro-NT定性结果具有良好一致性,两种试剂盒对恢复期血清样本的中和抗体滴度检测与micro-NT结果表现出了更强的相关性。

Objective To evaluate the performance of two commercial EIA kits for the detection of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)neutralizing antibodies.Methods Two commercial SARS-CoV-2 neutralizing antibody ELISA test kits(A and B)were used to detect serum panel consists of the following sera:44 collected before vaccination,120 collected one month after vaccination and 64 collected six months after recovery from convalescent patients of COVID-19.In the meantime,the above samples were also taken for live virus micro-neutralization test(micro-NT)indicated as the 50%neutralization antibody titer(NT50).The consistency of qualitative and quantitative results between the two commercial kits and live virus neutralization test was analyzed.Results Taking the micro-NT results as the standard,the positive coincidence rates of A and B kits were 97.40%and 100.00%,respectively;the negative coincidence rates were 97.30%and 95.95%,respectively;the Youden indices were 0.95 and 0.96,respectively.Furthermore,quantitative analysis indicated that the correlation coefficients between A and B kits and micro-NT results were 0.24(P<0.05)and 0.52(P<0.0001)for samples collected after vaccination,respectively;while the correlation coefficients were 0.81(P<0.0001)and 0.89(P<0.0001)for convalescent serum samples,respectively.Conclusions The results obtained by the two commercial neutralizing antibody detection kits were in good agreement with the qualitative results of micro-NT.The neutralizing antibody titers in convalescent serum samples detected by the two kits showed a stronger correlation with the micro-NT results.