FK506 as an adjuvant of tolerogenic DNA vaccination for the prevention of experimental autoimmune encephalomyelitis.

Background DNA vaccination is a strategy that has been developed primarily to elicit protective immunity against infection and cancer. Methods DNA vaccine was used, in conjunction with an immunosuppressant, to tolerize harmful autoimmunity. Results Immunization of C57BL/6 mice with MOG(35-55), a myelin oligodendrocyte glycoprotein-derived peptide, and FK506 (Tacrolimus) as a tolerogenic adjuvant stimulated regulatory dendritic cells, induced antigen-specific regulatory T cells (Treg), and protected the animals from subsequent induction of experimental autoimmune encephalomyelitis (EAE). After EAE there were fewer lymphocytes, including fewer T helper 17 cells, induction, and more Treg infiltrating the spinal cord in the immunized mice compared to in control mice. Furthermore, at the peak of the EAE manifestation, CD4 T cells in the immunized mice showed decreased expression of interferon-gamma and interleukin (IL)-17, but not IL-4, in treated mice. Conclusions DNA vaccination, when applied with an immunosuppressant as adjuvant, can induce antigen-specific tolerance and prevent autoimmune disease. Copyright (C) 2009 John Wiley & Sons, Ltd.