Autologous T-cell vaccination for multiple sclerosis: a perspective on progress.

T-cell vaccination (TCV) is a unique approach to induce immune regulation that may have importance in the treatment of autoimmune diseases, including multiple sclerosis (MS). TCV employs a classic vaccine strategy of injecting an attenuated form of the disease-causing agent--in this case, myelin-reactive T cells--that have been selected and expanded from each MS donor and then re-injected after irradiation to induce protective immunity. This anti-T-cell immunity consistently results in selective deletion or regulation of the targeted pathogenic T cells in vivo. Longitudinal studies have established that TCV is safe and often results in a reduced relapse rate and clinical stability or improvement, at least temporarily, in the majority of treated MS patients. These results lend direct support to the involvement of inflammatory myelin-reactive T cells in the MS disease process. However, these hopeful trends reported in a number of pilot trials await validation in larger proof-of-principle trials that are now in progress.