Evaluation of Nucleocapsid and Spike Protein-based ELISAs for detecting antibodies against SARS-CoV-2

Wanbing Liu; Lei Liu; Guomei Kou; Yaqiong Zheng; Yinjuan Ding; Wenxu Ni; Qiongshu Wang; Li Tan; Wanlei Wu; Shi Tang; Zhou Xiong; Shangen Zheng

The ongoing outbreak of coronavirus infectious disease 2019 (COVID-19) (1), 47 which emerged in Wuhan, China, is caused by a novel coronavirus named severe 48 acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (2-4). As of March 1, 2020, 49 more than 80,000 laboratory-confirmed cases have been reported in China (5), and the 50 disease has spread over 58 countries in Asia, Australia, Europe, and North America identified it as a Beta coronavirus and showed it is closely related (with 96% identity) 56 to Bat CoV RaTG13, but distinct from SARS-CoV (6). SARS-CoV-2 has a 57 receptor-binding domain (RBD) structure similar to that of SARS-CoV. Functionally 58 important ORFs (ORF1a and ORF1b) and major structural proteins, including the 59 spick (S), membrane (M), envelope (E), and nucleocapsid (N) proteins, are also well 60 annotated (7). According to previous reports, the M and E proteins are necessary for 61 virus assembly (8, 9) . The S protein is important for attachment to host cells, where 62 the RBD of S protein mediates the interaction with angiotensin-converting enzyme 2 63 (ACE2) (6). The S protein is located on the surface of the viral particles and has been 64 reported to be highly immunogenic (10). The N protein is one of the major structural 65 proteins of the virus and is involved in the transcription and replication of viral RNA, 66 packaging of the encapsidated genome into virions (11, 12) , and interference with cell 67 . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.