A Rapid, Multiplex Dual Reporter IgG and IgM SARS-CoV-2 Neutralization Assay for a Multiplexed Bead-Based Flow Analysis System

The COVID-19 pandemic has underscored the need for rapid high-throughput methods sensitive and specific serological detection of infection with novel pathogens, such as SARS-CoV-2. Multiplex testing can be particularly useful because it simultaneously analyze antibodies to multiple antigens that optimizes pathogen coverage, controls variability in organism individual host response. Here we describe a SARS-CoV-2 IgG 3-plex fluorescent microsphere-based assay detect both IgM three major antigens-the spike (S) protein, angiotensin-converting enzyme-2 (ACE2) receptor-binding domain (RBD), nucleocapsid (Nc). was shown have comparable performance reference serum obtained at ≥21 days from symptom onset but had higher sensitivity samples collected ≤5 onset. Further, using soluble ACE2 neutralization format, inhibition antibody binding demonstrated S RBD.