Establishment of murine hybridoma cells producing antibodies against spike protein of SARS-CoV-2

In 2020 the world faced the pandemic of COVID-19 - severe acute respiratory syndrome caused by a new type of coronavirus named SARS-CoV-2. To stop the spread of the disease, it is crucial to create molecular tools allowing to investigate, diagnose and treat COVID-19. One of such tools are monoclonal antibodies (mAbs). In this study we describe the development of hybridoma cells that can produce mouse mAbs against receptor binding domain of SARS-CoV-2 spike (S) protein. These mAbs are able to specifically detect native and denaturized S protein in all tested applications including immunoblotting, immunofluorescence staining and enzyme-linked immunosorbent assay. In addition, we showed that the obtained mAbs decreased infection rate of human cells by SARS-CoV-2 pseudovirus particles in in vitro experiments. Finally, we determined the amino acid sequence of light and heavy chains of the mAbs. This information will allow to use the corresponding peptides to establish genetically engineered therapeutic antibodies. To date multiple mAbs against SARS-CoV-2 proteins have been established, however due to the restrictions caused by pandemic, it is imperative to have a local source of the antibodies suitable for researches and diagnostics of COVID-19. Moreover, as each mAb has a unique binding sequence, bigger sets of various antibodies will allow to detect SARS-CoV-2 proteins even if the virus acquires novel mutations.