A Peptide-based Magnetic Chemiluminescence Enzyme Immunoassay for Serological Diagnosis of Coronavirus Disease 2019 (COVID-19)

Cai, Xue-fei; Chen, Juan; Hu, Jie-li; Long, Quan-xin; Deng, Hai-jun; Fan, Kai; Liao, Pu; Liu, Bei-zhong; Wu, Gui-cheng; Chen, Yao-kai; Li, Zhi-jie; Wang, Kun; Zhang, Xiao-li; Tian, Wen-guang; Xiang, Jiang-lin; Du, Hong-xin; Wang, Jing; Hu, Yuan; Tang, Ni; Lin, Yong; Ren, Ji-hua; Huang, Lu-yi; Wei, Jie; Gan, Chun-yang; Chen, Yan-meng; Gao, Qing-zhu; Chen, A-mei; He, Chang-long; Wang, Dao-Xin; Hu, Peng; Zhou, Fa-Chun; Huang, Ai-long; Liu, Ping; Wang, De-qiang

SARS-CoV-2, a novel ß-coronavirus, cause severe pneumonia and has spread throughout the globe rapidly. The disease associated with SARS-CoV-2 infection is named COVID-19. To date, real-time RT-PCR is the only test able to confirm this infection. However, the accuracy of RT-PCR depends on several factors; variations in these factors might significantly lower the sensitivity of detection. Here, we developed a peptide-based luminescent immunoassay that detected immunoglobulin G (IgG) and IgM. The assay cut-off value was determined by evaluating the sera from healthy and infected patients for pathogens other than SARS-CoV-2. To evaluate assay performance, we detected IgG and IgM in the sera from confirmed patients. The positive rate of IgG and IgM was 71.4% and 57.2%, respectively. Therefore, combining our immunoassay with real-time RT-PCR might enhance the diagnostic accuracy of COVID-19.