IgG2 Galactosylation is related to higher antibody dependent enhancement for dengue in cross-reactive antibodies from Sars-CoV-2

The study examined the relationship between sugar modifications on IgG2 antibodies (galactosylation) and the ability of cross-reactive antibodies induced by COVID-19 vaccination to cause antibody-dependent enhancement (ADE) in dengue virus. Researchers found a clear correlation between galactosylation of IgG2 against dengue virus and ADE capacity in individuals vaccinated against COVID-19. IgG2 sialylation increased over time but was not associated with ADE capacity. This phenomenon was limited to IgG2, while glycosylation of IgG1 against dengue virus remained stable after COVID-19 vaccination. The results suggest that specific sugar modifications on certain types of antibodies may influence the risk of more severe dengue infection in vaccinated individuals.