Revisiting tolerance induced by autoantigen in incomplete Freund's adjuvant.

Injection of autoantigens in IFA has been one of the most effective ways of preventing experimental, T cell-mediated, autoimmune disease in mice. The mechanism that underlies this protection has, however, remained controversial, with clonal deletion, induction of suppressor cells or of type 2 immunity being implicated at one time or another. Using high resolution enzyme-linked immunospot (ELISPOT) analysis, we have revisited this paradigm.