SUPPRESSION OF THE ALLERGIC REACTION IN A FOOD ALLERGY MOUSE MODEL THROUGH THE ORAL ADMINISTRATION OF HEAT-KILLED Tsukamurella inchonensis

DOCENA GH; SMALDINI PAOLA L; TREJO, FERNANDO M; BRUNET, LAURA; KAMPINGA, JAAP

Congreso; 16th International Congress of Mucosal Immunology; 2015

Society of Mucosal Immunology

Food allergy, a worldwide immune adverse reaction tocertain foods, is a growing clinical concern with no approved standardizedimmunotherapy. In this work we aimed to modulate milk allergy in a mouse model throughthe oral administration of a heat-killed Actinomyces bacteria (Tsukamurella inchonensis-Ti). Balb/c mice were sensitized with cow´s milk proteins(CMP) plus cholera toxin by gavage, and orally challenged with CMP to evidencehypersensitivity. Thereafter, Ti was orally administered during two months forimmunomodulation. Mice were challenged and treatment efficacy was in vivo (clinical score and cutaneoustest) and in vitro (serum specificantibodies and cytokines by ELISA, and cell analysis by flow cytometry) evaluated.Clinicalsigns and serum specific IgE levels were lower in Ti-treated mice compared withsensitized mice (p<0.05), with a concomitant reduction of IL-4 and IL-5. Ti-treatedmice showed a reduction of intestinal CD4+ CD25+ CD69+Teff cells with an increased frequency of lamina propria CD4+ CD25+FoxP3+ T cells (9.61±2.15% vs 6.15±0.25% Ti-treated and Sensitized,respectively). Intestinal IL-10 and IL-10+ FoxP3+ T cellswere up-regulated. Inconclusion, Ti induced Treg that controlled the Th2-medited allergic responses,with suppression of IgE. These findings may constitute the basis for apotential immunotherapy for food allergies.