Characterization of IL-33/ST2 axis in duodenal mucosae of Celiac Disease patients

FEDERICO PEREZ; DAVID DIAZ GIMÉNEZ; CAROLINA N. RUERA; MARCELA HERMOSO; GLAUBEN LANDSKRON; LUCIANA GUZMAN; FERNANDO G. CHIRDO; MARJORIE DE LA FUENTE; LAURA GARBI

Mar del Plata

Congreso; SAIC SAI SAFE 2016; 2016

Sociedad Argentina de Inmunología, Sociedad Argentina de Farmacología Experimental, Sociedad Argentina de Investigación clínica.

IntroductionOur previous studies showed upregulation of IL-33 alarmin and its receptor ST2 in duodenal mucosa of active Celiac Disease (CD) patients. Since these factors are known to play an important role in many different inflammatory diseases, we went further on to characterize which cells express IL-33 and ST2.MethodsDuodenal biopsies and blood samples were collected from paediatric and adult patients during the routine procedure for CD diagnosis. Immunofluorescence microscopy analysis was performed on sections of paraffin-embedded tissues. Serum levels of IL-33 were determined by commercial ELISA. ResultsWe found significant higher levels of IL-33 (p=0,012) in serum samples of CD patients (n=21) than in healthy population (n=9). In the duodenal lamina propria of these patients, we found that IL-33+ cells were mesenchymal cells identified by the expression of : Desmin, CD90, Vimentin, -Smooth Muscle Actin. Moreover, some of those cells seem to be associated with intestinal vasculature, possibly pericytes or endothelial cells. On the other hand, ST2+ cells were mainly CD138+ plasma cells, and a minor population were CD3+ or CD7+ T lymphocytes. ConclusionIn conclusion, we characterized that IL-33 and ST2 expressing cells in lamina propria of CD patients, were mainly mesenchymal cells and B lymphocytes, respectively. In addition to previous results, we demonstrated that not only ST2 soluble receptor was upregulated in serum of active CD patients, but also the alarmin IL-33. Since IL-33 is able to stimulate Th1 lymphocytes, cytotoxic cells, as well as actions on wound healing process, and also its alarmin functions allows us to connect the IL-33/ST2 axis and CD pathology.