In order to determine the mechanism(s) involved in the induction of immunologic tolerance for
contact sensitivity via the topical application of a chemical that sensitizes if given with adjuvant, we utilized the
hapten dinitrothiocyanobenzene (
DNTB). Specific immunologic tolerance to
dinitrofluorobenzene (
DNFB) was induced in mice by the topical application of
DNTB 7 days before sensitization to
DNFB. The tolerance could be abrogated if
cyclophosphamide (200 mg/kg) was given 3 days before attempted sensitization. Using passive transfer studies we found that
DNTB induced
hapten-specific Lyt 1+2- suppressor T cells. These suppressor cells prevented the induction of
contact sensitivity but did not affect its expression. Lymphocyte proliferation studies, using haptenated epidermal cells as
antigen, indicate that lymph node cells obtained 5 days after
DNFB sensitization are far less responsive if the mice have received
DNTB epicutaneously 7 days before the
DNFB. Binding studies demonstrated that
DNTB bound to epidermal cells at least as well as did
DNFB. It is postulated that
DNTB induction of suppressor cells is related to the physicochemical interaction between the
hapten and antigen-presenting cells in skin.