“…Although several interesting theories, e.g. cord blood IgE [2], cord blood eosinophil counts [3], maternal IgE in the placenta [4], macrophage‐derived chemokine (MDC; CCL22) [5, 6], infantile eosinophil counts [7], maternal IFN‐γ/IL‐4 ratios [8], eotaxin [9] and regulatory T cells [10], have been proposed, the precise mechanisms still remain under debate.…”