PMC

Autoimmunity can result from a loss of regulation of autoreactive T cells. Failures of regulatory T (T_Reg) cell-mediated regulation include: inadequate numbers of T_Reg cells owing to their inadequate development, proliferation or survival; defects in T_Reg cell function that is intrinsic to T_Reg cells; and resistance of pathogenic effector T cells to suppression by T_Reg cells owing to factors that are intrinsic to the effector cells or factors that are present in the inflammatory milieu and that support effector T cell resistance. DC, dendritic cell; IL, interleukin; TGFβ, transforming growth factor-β; T_H17, T helper 17.