[Delayed-type hypersensitivity induced by digestive immunization and suppression of this induction by antigen-antibody complexes (author's transl)].

BALB/c mice were immunized by intragastric administration of sheep red blood cells or horse red blood cells repeated daily for 4 days. The immunized animals when skin tested with an urea extract of the corresponding antigen showed a delayed-type hypersensitivity reaction. This reaction was observed for 4 weeks after the immunization. This result demonstrates that digestive immunization may induce cellular immunity. When serum from intragastrically immunised mice containing antigen-antibody complexes was administered intraperitoneally 8 hours before the onset of digestive immunization, the subsequent delayed-type hypersensitivity reaction was suppressed or considerably depressed.