Immunological mechanisms involved in experimental peptide immunotherapy of T-cell-mediated diseases.

Current therapies for autoimmune diseases and allergy involve general immune suppression. However, the ideal therapy should specifically eliminate or modulate the (auto)pathogenic immune response or, alternatively, it should reinforce the regulatory response, without affecting the overall function of the immune system. This could be achieved by antigen-specific immunotherapy. Antigen-specific immunotherapy has received ample attention in the last years, and several clinical trials attempting to treat autoimmune diseases or allergy through the induction of antigen-specific tolerance or immune deviation have been conducted, albeit with varying success. Recent advances in our understanding of peripheral tolerance, regulatory T cells, and routes of antigen administration have resulted in better insight into the different working mechanisms and potential target molecules of antigen-specific immunotherapy. The experimental animal models and new technological developments force the pace in the development of these immunotherapies. The current review addresses several aspects of antigen-specific immunotherapies and focuses on the mechanisms of the different approaches in experimental autoimmune and allergy models.