Retinoic acid-producing DCs and gut-tropic FOXP3+ regulatory T cells in the induction of oral tolerance

The systemic unresponsiveness of the immune system to orally administered antigens is known as oral tolerance. Recent findings describe a new step for the induction of oral tolerance, consisting in the homing of FOXP3(+) regulatory T cells to the small bowel and the local acquisition of full immunosuppressive capacities, a process in which retinoic acid-producing dendritic cells might play a crucial role.