A comparison between the active cutaneous Arthus reaction and immune-mediated enteroluminal neutrophil emigration in pigs.

The induction of neutrophil emigration into the intestinal lumen in bovine serum albumin immune and nonimmune pigs by mucosal exposure to bovine serum albumin was studied using a ligated intestinal loop technique. In order to compare the response in the skin to that in the intestine, test materials were inoculated intracutaneously as well as enterally. Several histochemical procedures were applied to the intestinal mucosa and skin for evaluation of responses. In immune animals, mucosal exposure to bovine serum albumin evoked the emigration of neutrophils into the intestinal mucosa and lumen. The neutrophil emigration tended to occur focally. Denudation of a few epithelial cells occurred at emigration sites. Hemorrhage, thrombosis, and edema, quite obvious after intracutaneous inoculation were not apparent after enteroluminal inoculation of bovine serum albumin into immune animals. Enteroluminal inoculation of bovine serum albumin or bovine serum albumin plus anti-bovine serum albumin into nonimmune animals did not elicit neutrophil emigration or any other pathological lesion in the intestine, whereas intracutaneous inoculation of bovine serum albumin plus anti-bovine serum albumin into the same animals elicited an Arthus reaction.