JEJUNAL RESPONSE TO BETA-LACTOGLOBULIN IN INFANTS WITH COWS MILK ALLERGY

Weaning is a transient period of life during which maternal proteins a re replaced by foreign proteins. Concomitantly, in early postnatal lif e, both digestive and immune systems undergo a maturation process. All ergy to cow's milk protein may develop in human infants during weaning , determining digestive, respiratory, cutaneous or systemic symptoms. We studied the intestinal response to bovine milk beta-lactoglobulin ( beta-LG) in infants with cow's milk allergy, first during the active p hase, and then during the symptom-free stage. During the active phase, transepithelial transport of the beta-LG across the intestinal epithe lial layer stimulated the sensitized subepithelial immune cells. This stimulation induced a rise in short-circuit current suggestive of an e lectrogenic chloride secretion and impaired protein handling by the ep ithelium. These findings underline the dual role of the epithelial lay er in intestinal function: on one hand, it takes an active part in all owing dietary antigens to stimulate the submucosal system, and on the other hand becomes the target for mediators involved in food allergy.