IFNG and allergic disease: The suppressive effects of IFN-γ on allergic diseases have been shown to be mediated by various mechanisms, such as the regulation of allergen presentation to T lymphocytes, the differentiation of naive T cells toward Th1 phenotype and/or inhibition of Th2 cell recruitment/differentiation, the suppression of Th2 cytokine release from activated T cells, and the induction of apoptosis in T cells and eosinophils (42–45).