Treating autoimmune diseases through restoration of antigen-specific immune tolerance.

The first line of treatment for many human autoimmune diseases involves the use of anti-inflammatory or immunosuppressive drugs such as prednisone or other steroids that not only suppress the underlying autoimmune disease, but lead to global suppression of the immune system. The sequelae of this approach include increased risk of infection, carcinogenesis, and osteoporosis. Moreover, such broad spectrum immunosuppression tends to have transient therapeutic benefit, as in many cases the disease becomes refractory to these drugs. There is a clear need for more specific means to restore immune tolerance to the specific autoantigens implicated in disease pathology. This review provides an overview of some of these newer, more specific therapeutic approaches to restoring immune tolerance to autoantigens, with an emphasis on those approaches that have been or will soon be tested in controlled clinical trials. Covered here are peptide- or protein-based therapeutics, oral tolerance, and cellular and gene therapy approaches to restoring antigen-specific immune tolerance.