Drug design for induction of antigen-specific immune tolerance

Allergies and autoimmune diseases caused by the breakdown of immune tolerance to harmless foreign antigens and self-antigens have been attracting attention in recent years as the number of patients increases. The development of antigen-specific immunotherapy for complete cure of allergies and autoimmune diseases, which artificially induces immune tolerance to antigens, has been studied. Immune tolerance therapy requires efficient and specific delivery of antigens to target immune cells, followed by induction of immune cells into a tolerogenic phenotype or anergy. In this process, drugs are required to perform three functions：evasion of the immune response to the antigen, targeting of the immune cells, and regulation of the immune cells. In this review, strategies and drug design for inducing antigen-specific immune tolerance are outlined, examples of recent research are presented, and future prospects are discussed.