Tolerance to the Trinitrophenol Ligand in Guinea Pigs: Studies on the Role of the Solvent Used in Feeding

Guinea pigs fed picryl sulfonic acid in aqueous solvents did not become unresponsive to contact sensitization with picryl chloride. In contrast, a substantial proportion of those fed picryl sulfonic acid, emulsified with triglyceride oil, were tolerant to subsequent immunization with picryl chloride. Feeding a related hapten (picryl chloride) in aqueous solvents was also considerably less effective in the induction of unresponsiveness to contact sensitization than feeding this hapten in vegetable oil. Animals fed picryl sulfonic acid in either aqueous or emulsified triglyceride solvents developed picryl-specific antibody after the initial feeding. However, those fed picryl chloride did not develop antibody and its role, if any, in the mechanism of unresponsiveness is unclear.