Anti-SARS-CoV-2 IgG and IgA antibodies in COVID-19 convalescent plasma do not enhance viral infection

• DOI: 10.1371/journal.pone.0257930
• Publication Date: 2022-03-08T18:38:30Z
• Authors: Natasha M. Clark; Sanath Kumar Janaka; William Hartman; Susan Stramer; Erin Goodhue; John Weiss; David T. Evans; Joseph P. Connor
• Keywords: Fc receptor; Convalescent plasma

The novel coronavirus, SARS-CoV-2 that causes COVID-19 has resulted in the death of nearly 4 million people within last 18 months. While preventive vaccination, and monoclonal antibody therapies have been rapidly developed deployed, early pandemic use convalescent plasma (CCP) was a common means passive immunization with theoretical risk antibody-dependent enhancement (ADE) viral infection. Though vaccines elicit strong protective immune response transfusion CCP high titers neutralization activity are correlated better clinical outcomes, question whether antibodies can enhance infection not directly addressed. In this study, we analyzed for observed transfer transfusion. Furthermore, to specifically understand if against spike protein (S) infection, measured anti-S IgG, IgA, IgM responses adapted retroviral-pseudotypes measure virus target cells expressing ACE2 receptor Fc alpha (FcαR) or gamma IIA (FcγRIIA). Whereas neutralizing best higher IgG antibodies, titer affected when receptors were present on cells. These observations support absence by IgA isotypes found CCP. results presented, therefore, only supports therapeutic currently available antibody-based treatment, including continuation strategies, but also various vaccine platforms prophylactic approach.