Results
After IL-10 DC priming and allergen-specific restimulation (Bet or Cor) non-specific control iTreg remained anergic, whereas Bet-specific iTreg proliferated extensively and exhibited a regulatory phenotype (enhanced expression of CTLA-4, PD-1, TNFR2, IL-10). Accordingly, activated Bet-specific iTreg displayed a high capacity to suppress Bet- and Cor-induced responder TH2 cell responses in vitro , indicating induction of both allergen-specific (birch) and cross-reactive tolerance (hazelnut). In vivo , the beneficial effect of Bet-specific iTreg was verified in humanized mouse models of allergic airway and intestinal inflammation, resulting in reduced allergen-induced clinical symptoms and immune responses.