RESUMO
PURPOSE: Food protein-induced enterocolitis syndrome (FPIES) is a symptom complex of vomiting and diarrhea caused by non-IgE mediated allergy to cow's milk and/or soy in young infants. Transforming growth factor (TGF)-beta has been reported to protect the epithelial barrier of the gut from foreign antigens. We studied the expression of type 1 and 2 TGF-beta receptors in the mucosa of small intestine to investigate their roles in the pathogenesis of FPIES. METHODS: Twenty-eight patients, aged 7 to 120 days (mean 49 days) who were diagnosed with FPIES by clinical criteria and challenge tests were included. Immunohistochemical stainings for type 1 and 2 TGF-beta receptors were performed on endoscopic duodenal biopsy specimens. RESULTS: Type 1 and 2 TGF-beta receptors were expressed in the villous and crypt epithelial cells but nearly absent in the lamina propria in both patients and controls. Type 1 TGF-beta receptor expression was significantly lower in the patients who had villous atrophy than in the patients who had not and in controls. The expression of type 1 TGF-beta receptor was negatively correlated with the severity of villous atrophy. Type 2 TGF-beta receptor expression showed no significant difference between the patients and controls. CONCLUSION: Our results suggests that the decreased activity of type 1 TGF-beta receptor is implicated in the pathogenesis of FPIES in young infants.