ORAL TOLERANCE IS NOT INFLUENCED BY ORAL APPLICATION OF OIL-EMULSIFIED PROTEINS

A 2-week program of feeding protein antigens as an oil-in-water emulsi on to naive mice elicited a significant serum IgG antibody response, w hereas their aqueous preparations did not at all. The unresponsive imm une state that had been developed after feeding aqueous antigen was no t disturbed by subsequent oral challenge with the same antigen in the presence of oil. These results suggest that the principle of oral tole rance is a feasible strategy for prophylaxis of hypersensitization to protein antigens, where protein tolerogens, in this case, are to be gi ven without any additives at their first introduction.