Anti-allergic effect of Lactobacillus helveticus SBT2171 on pollen allergen-induced allergy model

Background: We recently reported the suppressive effects of Lactobacillus helveticus SBT2171 (LH2171) on the proliferation and inflammatory cytokine production of primary murine immune cells in vitro. In this study, we investigated the effect of LH2171 on a murine pollen allergen-induced allergy model. Methods: Male BALB/c mice were fed a diet containing LH2171 (LH2171 group) or a diet not containing LH2171 (control group). Then, pollen allergy was induced by immunization with pollen extract emulsified in alum adjuvant and intranasal administration of pollen extract. To evaluate the anti-allergenic effect of LH2171, the antibody titer in plasma and expression of cytokines and transcription factors in immune tissues were analyzed by ELISA and qRT-PCR. Results: In the LH2171 group, the amounts of pollen-specific antibody and total IgE in plasma were significantly decreased compared with those in the control group. Proliferation and Th2 cytokine production were lower in the submandibular lymph node cells of the LH2171 group than in those of the control group. Moreover, in Peyer's patches, the gene expression of Il10 and Foxp3 were increased in the LH2171 group. Conclusion: LH2171 has the ability to suppress production of allergy-related antibody and Th2 cytokines, which could be correlated with the induction of anti-inflammatory factors in the intestinal immune system.