The IgG glycome of SARS-CoV-2 infected individuals reflects disease course and severity
Sterre L. Siekman, Tamás Pongrácz, Wenjun Wang, Jan Nouta, Peter G. Kremsner, Pedro V. da Silva‐Neto, Meral Esen, Andrea Kreidenweiss, Jana Held, Átila Alexandre Trapé, Rolf Fendel, Isabel Kinney Ferreira de Miranda Santos, Manfred Wuhrer
Abstract
Immunoglobulin G (IgG) antibodies play an important role in the immune response against viruses such as SARS-CoV-2. As the effector functions of IgG are modulated by N -glycosylation of the Fc region, the structure and possible function of the IgG N -glycome has been under investigation in relation to divergent COVID-19 disease courses. Through LC-MS analysis we studied both total IgG1 and spike protein-specific IgG1 Fc glycosylation of 129 German and 163 Brazilian COVID-19 patients representing diverse patient populations. We found that hospitalized COVID-19 patients displayed decreased levels of total IgG1 bisection and galactosylation and lowered anti-S IgG1 fucosylation and bisection as compared to mild outpatients. Anti-S IgG1 glycosylation was dynamic over the disease course and both anti-S and total IgG1 glycosylation were correlated to inflammatory markers. Further research is needed to dissect the possible role of altered IgG glycosylation profiles in (dys)regulating the immune response in COVID-19.