Maternal and postnatal dietary probiotic supplementation enhances splenic regulatory T helper cell population and reduces ovalbumin allergen-induced hypersensitivity responses in mice (HYP7P.305)

Abstract

Abstract Neonatal to early childhood is the critical period for establishing a balance of T helper 1 (Th1) versus T helper 2 (Th2) mucosal immunity, which is strongly influenced by the source and establishment of gut microflora. Probiotic administration has been shown to attenuate Th2-biased cellular immunity and predisposition to food allergies. To test this hypothesis we fed a probiotic-supplemented or control diet to lactating dams with suckling pups and weaned pups until 10 weeks of age. Weaned mice were sensitized with egg allergen ovalbumin, saline or adjuvant at 6, 8 and 10 weeks of age. At 3, 6, 8 and 10 weeks, fecal samples were collected for microbial analysis, while blood samples were analyzed for ovalbumin and total plasma IgE levels. At termination, splenic T helper population subtypes were determined by FACS analysis and gene expression by PCR array. At 21 days of age, pups suckled by lactating dams fed the probiotic supplemented diet had significantly enhanced Lactobacillus acidophilus fecal counts compared to controls. Moreover, mice fed the probiotic supplemented diet had enhanced splenic naturally occurring and induced regulatory T cell populations, enhanced TGFβ gene expression and reduced expression of allergic mediator IL13 compared to controls. These results provide evidence that early probiotic supplementation may provide host protection from hypersensitivity reactions to food allergens by attenuating food allergen inflammatory responses.