Certain types of regulatory T cells are preferentially induced at mucosal surfaces to maintain tolerance. However, the mechanisms involved in their induction are unclear. New evidence suggests DCs orchestrate this mucosal tolerogenic immune response. immunological events occur when antigen contacts the mucosal surfaces; different mechanism of tolerance are induced depending on the antigen, dose and route of administration. Thus, understanding the immunological milieu in which an antigen is processed by the immune system is crucial not only for understanding mucosal tolerance, but for understanding mechanisms of tolerance in general.

Akbari et al. showed that DCs are at the heart of immunological tolerance when the respiratory system is exposed to allergen and tolerance is dependent on IL-10. They treated mice that transgenically expressed a T cell receptor (TCR) specific for ovalbumin (OVA)