Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the cause of coronavirus disease 2019 (COVID-19). Little is known about the interplay between pre-existing immunity towards endemic seasonal coronaviruses and the development of a SARS-CoV-2-specific IgG response. We investigated the kinetics, breadth, magnitude and level of cross-reactivity of IgG antibodies against SARS-CoV-2 and heterologous seasonal and epidemic coronaviruses at the clonal level in mild and severe COVID-19 patients and disease control patients. Antibody reactivity towards nucleocapsid and spike antigens was assessed and correlated to SARS-CoV-2 neutralization. COVID-19 patients mounted a mostly type-specific SARS-CoV-2 response. Additionally, IgG clones directed against seasonal coronavirus were boosted in patients with severe COVID-19. These boosted clones showed limited cross-reactivity and did not neutralize SARS-CoV-2. These findings support a boost of poorly protective coronavirus-specific antibodies in COVID-19 patients that correlates with disease severity, revealing original antigenic sin.
Muriel Aguilar-Bretones, Brenda M. Westerhuis, Matthijs P. Raadsen, Erwin de Bruin, Felicity D. Chandler, Nisreen M.A. Okba, Bart L. Haagmans, Thomas Langerak, Henrik Endeman, Johannes P.C. van den Akker, Diederik A.M.P.J. Gommers, Eric C.M. van Gorp, Corine H. GeurtsvanKessel, Rory D. de Vries, Ron A.M. Fouchier, Barry H.G. Rockx, Marion P.G. Koopmans, Gijsbert P. van Nierop