Tolerance and contact sensitivity to DNFB in mice. V. Induction of tolerance with DNP compounds and with free and membrane-associated DNFB.

Immunologic unresponsiveness (tolerance) was induced in a mouse model of contact sensitization to DNFB. The ability to induce tolerance varied with the chemical reactivity of the tolerogen; DNFB was highly tolerogenic, DNBSO3 was moderately tolerogenic, and DNP-lysine was not tolerogenic. Although DNFB is considered a highly reactive compound, tracer studies of injected DNFB showed that it was rapidly excreted. Further studies were therefore done with DNFB attached to mouse erythrocytes. Tolerance to DNFB-RBC was highly specific in vivo; mice tolerant to DNFB showed normal reactivity to TNCB (picryl chloride.) Cells of mice tolerant to DNFB-RBC were also unresponsive to DNBSO3 in vitro. Tolerance to DNFB, DNBSO3, and DNFB-RBC all required time to develop, suggesting that an active process was involved.