Figure 1. Hypothesized Tregitope mechanism of action. Treg epitopes (Tregitopes) present in Fc and Fab domain of IgG drive tolerance to neo-epitopes pre-sent in the Fab hypervariable domains. EpiVax discovered conserved T -cell epitopes in IgG that engage natural Treg. We hypothesize that Tregitopes (dark blue) activate Treg that lead to bystander suppression of effector T cells that recognize effector epitopes (red) and, depending on the context, induction of antigen-specific Tregs (aTregs) to these epitopes.