FCGR3A and infection: These bind closely spaced IgG Fc pairs to mimic the engagement and cross-linking of FcγR pairs by IgG-opsonized virus or infected cells.32–36 Binding is further influenced by the IgG subclass and, in the case of FcγRIIIa, glycosylation of the Fc domain.37 We examined longitudinal serum samples from HIV-infected subjects, who commenced ART close to the time of seroconversion, to address the Fc receptor-mediated functionality of anti-HIV Ab responses early in infection, their decline during ART, and boosting during structured treatment interruption (STI).