DNA vaccination has been used to generate effective cellular as well as humoral immunity against target antigens. Here we have investigated the induction and involvement of regulatory T cell (T_reg) responses in mediating prevention of experimental autoimmune encephalomyelitis (EAE), following vaccination with plasmid DNA encoding the TCR V_β8.2 chain predominantly displayed on disease-causing lymphocytes. Vaccination with DNA encoding the wild-type TCR results in priming of type 1 CD4 T_reg and skewing of the global response to myelin basic protein in a T_h2 direction, leading to significant protection from disease. In contrast, vaccination with mutant DNA encoding altered residues critically involved in recognition by the T_reg results in priming of a type 2 regulatory response which fails to mediate immune deviation or protection from EAE. Control mice immunized with DNA, encoding TCR with changes at an irrelevant site, were protected from antigen-induced disease. Furthermore, protection can be transferred into naive recipients with CD4 T_reg from wild-type DNA-immunized mice but not from animals vaccinated with the mutant DNA. These data suggest that vaccination with plasmid DNA encoding one or multiple V_β genes can be exploited to enhance natural regulatory responses for intervention in autoimmune conditions.