IgA MAb blocks SARS-CoV-2 Spike-ACE2 interaction providing mucosal immunity

Ejemel, M.; Li, Q.; Hou, S.; Schiller, Z. A.; Wallace, A. L.; Amcheslavsky, A.; Kurt Yilmaz, N.; Toomey, J. R.; Schneider, R.; Close, B. J.; Chen, D.-Y.; Conway, H. L.; Saeed, M.; Cavacini, L. A.; Klempner, M. S.; Schiffer, C. A.; Wang, Y.

doi:10.1101/2020.05.15.096719

bioRxiv · 10.1101/2020.05.15.096719

IgA MAb blocks SARS-CoV-2 Spike-ACE2 interaction providing mucosal immunity

Ejemel, M.·Li, Q.·Hou, S.·Schiller, Z. A.·Wallace, A. L.·Amcheslavsky, A.·Kurt Yilmaz, N.·Toomey, J. R.·Schneider, R.·Close, B. J.·Chen, D.-Y.·Conway, H. L.·Saeed, M.·Cavacini, L. A.·Klempner, M. S.·Schiffer, C. A.·Wang, Y.

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Abstract

COVID-19 caused by SARS-CoV-2 has become a global pandemic requiring the development of interventions for the prevention or treatment to curtail mortality and morbidity. No vaccine to boost mucosal immunity or as a therapeutic has yet been developed to SARS-CoV-2. In this study we discover and characterize a cross-reactive human IgA monoclonal antibody, MAb362. MAb362 binds to both SARS-CoV and SARS-CoV-2 spike proteins and competitively blocks hACE2 receptor binding, by completely overlapping the hACE2 structural binding epitope. Furthermore, MAb362 IgA neutralizes both pseudotyped SARS-CoV and SARS-CoV-2 in human epithelial cells expressing hACE2. SARS-CoV-2 specific IgA antibodies, such as MAb362, may provide effective immunity against SARS-CoV-2 by inducing mucosal immunity within the respiratory system, a potentially critical feature of an effective vaccine.

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Ejemel, M., Li, Q., Hou, S., Schiller, Z. A., Wallace, A. L., Amcheslavsky, A., Kurt Yilmaz, N., Toomey, J. R., Schneider, R., Close, B. J., Chen, D.-Y., Conway, H. L., Saeed, M., Cavacini, L. A., Klempner, M. S., Schiffer, C. A., Wang, Y.. 2020-05-15. IgA MAb blocks SARS-CoV-2 Spike-ACE2 interaction providing mucosal immunity. https://doi.org/10.1101/2020.05.15.096719

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