RESUMO
The onset of severe SARS-CoV-2 infection is characterized by the presence of afucosylated IgG1 responses against the viral spike (S) protein, which can trigger exacerbated inflammatory responses. Here, we studied IgG glycosylation after BNT162b2 SARS-CoV-2 mRNA vaccination to explore whether vaccine-induced S protein expression on host cells also generates afucosylated IgG1 responses. SARS-CoV-2 naive individuals initially showed a transient afucosylated anti-S IgG1 response after the first dose, albeit to a lower extent than severely ill COVID-19 patients. In contrast, previously infected, antigen-experienced individuals had low afucosylation levels, which slightly increased after immunization. Afucosylation levels after the first dose correlated with low fucosyltransferase 8 (FUT8) expression levels in a defined plasma cell subset. Remarkably, IgG afucosylation levels after primary vaccination correlated significantly with IgG levels after the second dose. Further studies are needed to assess efficacy, inflammatory potential, and protective capacity of afucosylated IgG responses. One sentence summaryA transient afucosylated IgG response to the BNT162b2 mRNA vaccine was observed in naive but not in antigen-experienced individuals, which predicted antibody titers upon the second dose.
RESUMO
The novel SARS-CoV-2 virus emerged in late 2019 and has caused a global health and economic crisis. The characterization of the human antibody response to SARS-CoV-2 infection is vital for serosurveillance purposes as well for treatment options such as transfusion with convalescent plasma or immunoglobin products derived from convalescent plasma. In this study, we measured antibody responses in 844 longitudinal samples from 151 RT-PCR positive SARS-CoV-2 convalescent adults during the first 34 weeks after onset of symptoms. All donors were seropositive at the first sampling moment and only one donor seroreverted during follow-up analysis. Anti-RBD IgG and anti-nucleocapsid IgG levels slowly declined with median half-lifes of 62 and 59 days during 2-5 months after symptom onset, respectively. The rate of decline of antibody levels diminished during extended follow-up. In addition, the magnitude of the IgG response correlated with neutralization capacity measured in a classic plaque reduction assay as well in our in-house developed competition assay. The result of this study gives valuable insight into the longitudinal response of antibodies to SARS-CoV-2.
