Characterisation of immune mediator release during the immediate response to segmental mucosal challenge in the jejunum of patients with food allergy

Background-Food allergy is a common complaint among patients with a broad s pectrum of abdominal and extraabdominal symptoms that must be distinguished from other more common non-immunological food intolerances. Aims-To investigate whether human intestinal hypersensitivity reactions are associated with detectable release of inflammatory mediators from activate d cells, which may serve as a biological marker of true allergic reactions. Patients/Methods-In eight patients with food allergy and seven healthy volu nteers, a closed-segment perfusion technique was used to investigate the ef fects of jejunal food challenge on luminal release of tryptase, histamine, prostaglandin D-2, eosinophil cationic protein, peroxidase activity, and wa ter flux. Results-Intraluminal administration of food antigens induced a rapid increa se in intestinal release of tryptase, histamine, prostaglandin D-2, and per oxidase activity (p < 0.05 v basal period) but not eosinophil cationic prot ein. The increased release of these mediators was associated with a notable water secretory response. Conclusions-These results suggest that human intestinal hypersensitivity re actions are characterised by prompt activation of mast cells and other immu ne cells, with notable and immediate secretion of water and inflammatory me diators into the intestinal lumen. Analysis of the profile of markers relea sed into the jejunum after food provocation may be useful for the objective diagnosis of food allergy.