IL-2/anti-IL-2 complex treatment induces regulatory T cells and ameliorates experimental food allergy

SMALDINI PAOLA; TREJO FERNANDO; COHEN JOSÉ; PIAGGIO ELIANE; DOCENA GUILLERMO

Mar del Plata

Congreso; Congreso conjunto SAIC-SAI-SAFE, LXIV Reunión Anual de SAI; 2016

SAI

Cow?s milk allergy (CMA), mediated by an aberrant immunological reaction to cow?s milk proteins (CMP), is one of the most prevalent food allergies in infants and young children worldwide. Oral and sublingual immunotherapies show promise as potential disease-modifying therapies, although no therapy has yet been approved. It has recently been demonstrated that the IL-2/ anti-IL-2 complex selectively expands regulatory T cells (Tregs). We aimed to combine sublingual immunotherapy (SLIT) using low doses of the allergen with systemic administration of IL-2/anti-IL2 to improve the safety and efficacy of the sublingual therapyBalb/c mice were sensitized with CMP and cholera toxin and then treated with PBS (Sens) or CMP (CMPdes) (sublingual) plus intraperitoneal injections of IL-2/anti-IL-2 (C or CMPdes/C). Mice were orally challenged with CMP and the immune response was in vitro (serum IgE, IL-5 and IFN-γ secretion by splenocytes, lamina propria Tregs, IL-10 and TGF-β) and in vivo (clinical score and cutaneous tests) evaluatedWe found a lower medium clinical score in treated mice after the oral challenge with CMP, as compared with sensitized mice, with a reduction in skin mast cell reactivity in treated mice, mainly in CMPdes/C group. Immunological changes included decreased specific IgE (2,1±0,3OD Sens vs 1,3±0.1CMPdes; 1,4±0,9C; 1,1±0,8CMPdes/C), decreased levels of Th2 cytokines and induction of IL-10 and Tregs in lamina propria of duodenum (14,6±1,2% Sens vs 28,0±0,6% CMPdes; 35,2±3,1% C; 42,5±1,8% CMPdes/C) and of sublingual mucosa of treated mice (p