Fig. 4.

A hypothetical mechanistic model for PDCs’ function in the homeostasis, stimulatory and regulatory mode. Reposing State: In this state, immature PDCs introduce antigens in a tolerogenic manner and regulatory cytokines and factors such as TGFβ and IL10 help maintain tolerance. Stimulating State: In this state, mature PDCs and stimulatory T cells defeating tolerance barrier and pro-inflammatory cytokines such as IL6 promoting conversion of regulatory T cells into effector Th17-like Tcells expressing IL-17 and T1D develops. Regulating State : Mature PDCs provoke abortive T cell responses, activate T regs and suppress inflammatory cytokine production, mediated by IDO