Immunological Tolerance Induced in Animals Previously Sensitized to Simple Chemical Compounds

Abstract

Adult guinea pigs develop a delayed hypersensitivity to intradermally injected neoarsphenamine. If the animals are treated intravenously with high doses of this compound before sensitization, a specific and permanent immunological tolerance develops. Permanent tolerance is also obtained in previously sensitized animals when an intravenous injection of neoarsphenamine isfollowed 6 hours later by an intradermal one. When, however, the interval between the two injections is extended to 7 or 14 days, no tolerance is observed.

Differing mechanisms of tolerance and desensitization to dinitrochlorobenzene in guinea pigs

“…Complete suppression of contact sensitivity was achieved by injecting the hapten intravenously. The unresponsiveness so induced was permanent when normal guinea pigs were treated with the tolerogen before the attempted sensitization (tolerance) [ 2,3], but only temporary when the hapten was applied t o presensitized animals (desensitization) [4].…”

Sensitization, Immunological Tolerance and Desensitization of Guinea Pigs to Neoarsphenamine I.

“…First, NEO has been in our hands a good model system for induction of immunological tolerance and especially for induction of longlasting desensitization in already sensitized animals (22). Second, our investigation has put in evidence the role of various factors operative in experimental sensitization with weak sensitizers.…”

Sensitization, Immunological Tolerance and Desensitization of Guinea Pigs to Neoarsphenamine III.

“…T u r k (28) and our group (15) succeeded in inducing a complete, specific and long lasting immunological tolerance to DNCB by intravenous pre treatment with dinitrobenzene sulfonate (DNBS03). As our tech nique resembled closely that used by Frei and Sulzberger, we decided to repeat and extend their experiments with NEO, which we could fully confirm as we have already reported in part in a preliminary communication (17).…”