IFNG and allergic disease: As a typical anti-allergic probiotic, L. salivarius helps reduce the production of specific IgE antibodies in serum, promotes the secretion of interferon (IFN-γ) in spleen cells, and enhances the TH1-type immune response to regulate the TH2-type immune response which is overactive due to allergies (Iwamoto et al., 2010; Li et al., 2010).