In vivo DNP tolerance induction by DNP-ficoll.

The kinetics of tolerance induction by administration of two different doses of DNP78-Ficoll on the anti-DNP IgM immune response in AJ mice was studied. The tolerogenic effects of 100 microgram of DNP78-Ficoll begin earlier and last longer than those of 10 microgram of DNP78-Ficoll as determined by the development of direct anti-DNP plaque-forming cells in the spleen and anti-DNP antibody titers in serum. In cell-transfer experiment, DNP tolerance was unstable. Transfer experiments did not produce detectable tolerogenic factors in serum. Antigen-antibody complexes, that tend to produce local suppressor effects, are discussed as mediators of tolerance.