Lactic acid bacteria (LAB) in fermented foods have attracted considerable attention recently as treatment options for allergic diseases, the incidence of which has been increasing worldwide. Five strains of LAB isolated from kimoto, the traditional seed mash used for brewing sake, were screened for the ability to suppress IgE-mediated hypersensitivity reaction. Leuconostoc mesenteroides and Lactobacillus sakei, the normal microflora in kimoto, significantly suppressed the reaction, but the contaminant Lactobacillus curvatus did not. Next, we examined the effect of L sakei LK-117 on atopic dermatitis in the NC/Nga mouse model. LK-117 supplementation significantly reduced the development of atopic dermatitis-like skin lesions in a manner independent of the IgE plasma levels. In the in vitro intestinal model constructed using the human intestinal epithelial cell line Caco-2 and murine macrophage cell line RAW 264.7, treatment with L sakei LK-117, but not L curvatus, significantly upregulated TNE-alpha production from RAW264.7 cells. This result indicated that L sakei on the apical side affected the macrophages on the basolateral side, and this organism may have the ability to improve allergy symptoms mediated by the intestinal immune system. (C) 2012, The Society for Biotechnology, Japan. All rights reserved.