Establishment of a Serological Panel for In Vitro Diagnostics of Severe Acute Respiratory Syndrome

Severe acute respiratory syndrome (SARS) is an infectious disease with a high mortality rate. Because SARS suddenly disappeared after an approximately 1-year-long pandemic period (November 2002 to July 2003), insufficient data was available for the development of in vitro diagnostics for SARS (SARS IVD). To rapidly identify cases in the event of future epidemics, it is necessary to establish a SARS serological panel. In this study, 20 SARS convalescent sera and 20 normal sera from the Taiwan CDC were used to establish a SARS serological panel. This can be used as a standard for the Taiwan FDA to evaluate the effectiveness of SARS IVDs during the premarket approval process. To characterize the immunological activity, protein extracts containing SARS coronavirus (SARS-CoV) proteins, synthetic viral peptide fragments and recombinant viral proteins, were used to detect antibody reactivity. Results demonstrated that synthetic S, M, N peptide fragments and whole SARS-CoV protein extracts had stronger antigenicity than individual recombinant viral proteins. Moreover, results of the ELISA and the immunofluorescence assay indicated that our SARS panel had no cross-reactivity with the human coronavirus 229E, and displayed weak cross-reactivity with human coronavirus OC43. These findings suggested that our SARS serological panel is suitable for evaluating SARS IVDs.