Division for Health Service Promotion, The University of Tokyo, Japan.
Division for Health Service Promotion, The University of Tokyo, Japan.
J Infect Chemother. 2021 Sep;27(9):1342-1349. doi: 10.1016/j.jiac.2021.06.008. Epub 2021 Jun 12.
The worldwide pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has continued to date. Given that some of the patients with coronavirus disease 2019 (COVID-19) are asymptomatic, antibody tests are useful to determine whether there is a previous infection with SARS-CoV-2. In this study, we measured IgM and IgG antibody titers against SARS-CoV-2 in the serum of asymptomatic healthy subjects in The University of Tokyo, Japan.
From June 2020, we recruited participants, who were students, staff, and faculty members of The University of Tokyo in the project named The University of Tokyo COVID-19 Antibody Titer Survey (UT-CATS). Following blood sample collection, participants were required to answer an online questionnaire about their social and health information. We measured IgG and IgM titers against SARS-CoV-2 using iFlash-SARS-CoV-2 IgM and IgG detection kit which applies a chemiluminescent immunoassay (CLIA) for the qualitative detection.
There were 6609 volunteers in this study. After setting the cutoff value at 10 AU/mL, 32 (0.48%) were positive for IgG and 16 (0.24%) for IgM. Of six participants with a history of COVID-19, five were positive for IgG, whereas all were negative for IgM. The median titer of IgG was 0.40 AU/mL and 0.39 AU/mL for IgM. Both IgG and IgM titers were affected by gender, age, smoking status, and comorbidities.
Positive rates of IgG and IgM titers were relatively low in our university. Serum levels of these antibodies were affected by several factors, which might affect the clinical course of COVID-19.
严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）的全球大流行仍在继续。鉴于一些 2019 年冠状病毒病（COVID-19）患者无症状，抗体检测可用于确定是否以前感染过 SARS-CoV-2。在这项研究中，我们测量了日本东京大学无症状健康受试者血清中针对 SARS-CoV-2 的 IgM 和 IgG 抗体滴度。
从 2020 年 6 月开始，我们招募了参与名为东京大学 COVID-19 抗体滴度调查（UT-CATS）的项目的学生、工作人员和教职员工。采集血样后，参与者需要在线回答一份关于其社会和健康信息的问卷。我们使用 iFlash-SARS-CoV-2 IgM 和 IgG 检测试剂盒测量针对 SARS-CoV-2 的 IgG 和 IgM 滴度，该试剂盒采用化学发光免疫分析（CLIA）进行定性检测。
本研究共有 6609 名志愿者。将截断值设定为 10 AU/mL 后，32 人（0.48%）IgG 阳性，16 人（0.24%）IgM 阳性。在有 COVID-19 病史的六名参与者中，五人 IgG 阳性，而所有人 IgM 均为阴性。IgG 的中位数滴度为 0.40 AU/mL，IgM 为 0.39 AU/mL。IgG 和 IgM 滴度均受性别、年龄、吸烟状况和合并症的影响。
我们大学 IgG 和 IgM 滴度的阳性率相对较低。这些抗体的血清水平受多种因素影响，可能影响 COVID-19 的临床病程。
