Sino Biological has developed a serosurveillance tool that will provide vital COVID-19 epidemiological data and vital information for vaccine developers on how antibodies interact with SARS-CoV-2 antigens.

The Sinommune™ Multiplex Antigen Microarray was jointly developed with Nanoimmune Inc., a California-based biotechnology company who specialize in multiplex array technology. 

The multiplex array consists of slides made of nitrocellulose, with pads containing a single array where hundreds of recombinant antigen spots have been pre-printed and adsorbed onto the 3-D nitrocellulose slide's topography.

Each array determines the antibody profile in serum samples and monitors its changes over time and under different circumstances. 

The Sinommune microarray consists of 65 viral antigens from six major groups of the viral superfamily (including SARS-CoV-2 and other human coronaviruses) that can lead to respiratory infections. A study was carried out by researchers at University of California Irvine (UCI), Cerus Corporation, University of Maryland, Oregon Health and Science University, and the Vitalant Research Institute to determine the reactivity between antibodies and the recombinant antigens and was published on bioRxiv.

Using confirmed COVID-19 convalescent blood specimens and negative sera taken before the epidemic; the Sinommune microarray captured a distinct antibody profile for SARS-CoV-2 only.

The study also showed both groups had comparable reactivity towards antigens from the common cold and other virus types, 

Figure 1. reveals the heat map from the microarray study, where a distinct IgG reactivity can be seen towards SARS-CoV-2.

Not only does this serosurveillance tool have the potential to determine the prevalence of the infection during an epidemic but will aid in the correlation between antibody responses and clinical outcomes in further studies of COVID-19.