SARS-CoV-2 IgG 检测试剂盒（针对核衣壳蛋白和刺突蛋白）的比较评估。

Comparative evaluation of SARS-CoV-2 IgG assays against nucleocapsid and spike antigens.

机构信息

Clinical Tuberculosis and Epidemiology Research Center, National Research Institute of Tuberculosis and Lung Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Virology Research Center, National Research Institute of Tuberculosis and Lung diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

出版信息

Hum Antibodies. 2021;29(2):109-113. doi: 10.3233/HAB-210440.

DOI:10.3233/HAB-210440

PMID:33720878

Abstract

BACKGROUND

There are few studies to compare antibody response against anti-spike (S) and anti- nucleoprotein (N) SARS-CoV-2.

OBJECTIVE

The aim of this study was to evaluate the IgG antibody production against S and N antigens of the virus and their correlation with the time and severity of the disease.

METHODS

The IgG antibodies against S and N antigens of SARS-CoV-2 in serum specimens of 72 symptomatic patients who tested real-time reverse transcription polymerase chain reaction positive for SARS-CoV-2 were detected using the ELISA technique. Different antibody response was compared and the correlation with the time from disease onset and the severity was evaluated.

RESULTS

Forty-eight of 72 (67%) patients tested positive for anti-SARS-CoV-2 antibodies, while 24 (33%) did not have detectable antibodies. Comparison of antibody levels for N and S antibodies showed that they correlate with each other well (r= 0.81; P< 0.001). However, sensitivity of anti-S SARS-CoV-2 IgG and anti-N SARS-CoV-2 IgG was 30% and 60%, during the first 7 days after symptom onset (r= 0.53; P= 0.111), but increased to 73% and 68% at more than 1-week post symptom onset (r= 0.89, P= 0.111), respectively. Cases with positive IgG response showed a decreased CD8+ T cells percentage compared to the negative IgG groups (26 ± 14 vs. 58 ± 32, p= 0.066 in anti-N IgG group and 28 ± 15 vs. 60 ± 45, p= 0.004 in anti-S IgG group, respectively).

CONCLUSION

Nearly one-third of the confirmed COVID-19 patients had negative serology results. Lower percent positivity at early time points after symptom onset (less than 1 week) was seen using anti-S SARS-COV-2 IgG kit compare to the anti-N SARS-CoV-2 IgG; therefore, clinicians should interpret negative serology results of especially anti-S SARS-CoV-2 IgG with caution.

摘要

背景

目前很少有研究比较针对刺突（S）和核蛋白（N）的 SARS-CoV-2 抗体反应。

目的

本研究旨在评估针对病毒 S 和 N 抗原的 IgG 抗体产生情况，并分析其与疾病时间和严重程度的相关性。

方法

采用酶联免疫吸附试验（ELISA）技术检测 72 例实时逆转录聚合酶链反应（RT-PCR）检测 SARS-CoV-2 阳性的症状性患者血清标本中针对 SARS-CoV-2 的 S 和 N 抗原的 IgG 抗体。比较不同的抗体反应，并评估与疾病发病时间和严重程度的相关性。

结果

72 例患者中，48 例（67%）检测到抗 SARS-CoV-2 抗体阳性，24 例（33%）未检测到抗体。N 和 S 抗体的抗体水平比较表明，它们之间具有很好的相关性（r=0.81；P<0.001）。然而，在症状出现后的前 7 天内，抗 SARS-CoV-2 IgG 和抗 N SARS-CoV-2 IgG 的敏感性分别为 30%和 60%（r=0.53；P=0.111），但在症状出现后 1 周以上时，敏感性分别增加至 73%和 68%（r=0.89，P=0.111）。与 IgG 阴性组相比， IgG 阳性反应组的 CD8+T 细胞百分比下降（抗 N IgG 组为 26±14%对 58±32%，P=0.066；抗 S IgG 组为 28±15%对 60±45%，P=0.004）。

结论

近三分之一的确诊 COVID-19 患者血清学检测结果为阴性。与抗 N SARS-CoV-2 IgG 相比，在症状出现后早期（不到 1 周），使用抗 SARS-CoV-2 IgG 试剂盒检测到的 SARS-CoV-2 阳性率较低；因此，临床医生应谨慎解读抗 SARS-CoV-2 IgG 的阴性血清学结果。