ORF8 and ORF3b antibodies are accurate serological markers of early and late SARS-CoV-2 infection

The luciferase immunoprecipitation system (LIPS) identifies the existence of viral protein-specific antibodies in the sera from COVID-19 patients. By using this LIPS to survey antibodies against all types of SARS-CoV-2 protein, it was demonstrated that antibodies against ORF8 and ORF3b proteins, as well as spike (S) and nucleocapsid (N) proteins were remarkably detected in the sera. Both ORF8 and ORF3b are known as host immune-response antagonists during viral infection. Although serological diagnostic test for SARS-CoV-2 infection is currently based on the detection of S and N protein antibodies, this study proposes that measurement of antibodies against ORF8 and ORF3b may be useful to be an alternative method.