A Th2 enviroment delineates the inflammatory infiltrate of colonic polyps in food allergy

PUCCI MOLINERIS MELISA; NANFITO GABRIELA; ALTAMIRANO EUGENIA; DE LA FUENTE MARJORIE; CARLOS A. FOSSATI; CANZIANI KARINA; DIAZ JIMENEZ DAVID; GARCIA MARCELA; CUETO RUA EDUARDO; RAMELLO HERMOSO MARCELA; DOCENA GUILLERMO H.; BALCARCE NORMA; GUZMAN LUCIANA; MEIER DOMINIK; LANDSKRON GLAUBEN; MUGLIA CECILIA

VENTURA (CALIFORNIA)

Conferencia; Gordon Research Conference : Mechanisms, Prevention of, and Emerging Therapies for Food Allergy; 2018

Polyps in the colon of children with allergy have been poorly investigated and not related with food allergy. In this work we examined the stroma of colonic polyps to probe an association with atopy in paediatric patients.Colonic polyps were excised in 18 children out of 44 that underwent colonoscopy for rectal bleeding. A personal and family history of atopy, serum IgE and skin tests were assessed. Infiltrating cells, cytokines and chemokines were studied in polyp tissue (PT), surrounding colonic tissue (SCT) and colonic tissue from healthy subjects (HCT) by histology, immunohistochemistry, confocal microscopy, ELISA, flow cytometry and qRT-PCR. Patients had a personal and/or family history of atopy and milk-specific serum IgE (11/18). Polyps were pedunculated and mostly located in the rectum. Lymphocytes and eosinophils predominated in PT, while SCT was normal. IgE was found in plasma cells and eosinophils in PT, while in SCT IgA plasma cells predominated. PT showed the presence of diverse active germinal centres with IgE plasma cells in the periphery. PT showed higher levels of IL-4, IL-5, IL-13 and lower levels of IL-17 and IFN-γ compared with SCT. The ratio IL-13/IFN-γ was increased in PT. In addition, Eotaxin-3 and eosinophil count were higher in PT compared with SCT. Finally, ST2 and IL-33 were augmented in PT and serum soluble ST2 was increased in patients.We found an allergic inflammatory infiltrate in colonic polyps, with eosinophils, active germinal centres, IgE plasma cells, elevated eosinophil-attractant chemokine, Th2-cytokines, IL-33 and ST2 in atopic patients.