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

TREJO, FERNANDO M; DOCENA, GUILLERMO H; SMALDINI PAOLA LORENA; PIAGGIO, ELIANE; COHEN, JOSE

Mar del Plata

Congreso; Congreso de la Sociedad Argentina de Inmunología (SAI). LXIII Reunión científica anual; 2016

Sociedad Argentina de Inmunologia

Cow?s milk allergy (CMA), mediated by an aberrant immunological reaction tocow?s milk proteins (CMP), is one of the most prevalent food allergies in infants and youngchildren worldwide. Oral and sublingual immunotherapies show promise as potentialdisease-modifying therapies, although no therapy has yet been approved. It has recentlybeen 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 theallergen with systemic administration of IL-2/anti-IL2 to improve the safety and efficacy ofthe sublingual therapyBalb/c mice were sensitized with CMP and cholera toxin and then treated with PBS(Sens) or CMP (CMPdes) (sublingual) w/wo intraperitoneal injections of IL-2/anti-IL-2 (Cor CMPdes/C). Mice were orally challenged with CMP and the immune response was invitro (serum IgE, IL-5 and IFN-γ secretion by splenocytes, lamina propria Tregs, IL-10 andTGF-β) and in vivo (clinical score and cutaneous tests) evaluatedWe found a lower medium clinical score in treated mice after the oral challengewith CMP, as compared with sensitized mice, with a reduction in skin mast cell reactivityin treated mice, mainly in CMPdes/C group. Immunological changes included decreasedspecific IgE (2,1±0,3OD Sens vs 1,3±0.1CMPdes; 1,4±0,9C; 1,1±0,8CMPdes/C), decreasedlevels 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 ofsublingual mucosa of treated mice (p