Anti-atopic dermatitis effects and the mechanism of lactic acid bacteria isolated from Mongolian fermented milk.
We investigated the anti-allergic effects of one strain (T120) of a lactic acid bacteria (LAB) isolated from Mongolian fermented milk using atopic dermatitis (AD) model mice (NC/Nga mice). Strain T120 has already been identified as Enterococcus faecium and shown to induce strong production of IL-12 (Kimura et al. 2006). In in vitro studies, strain T120 suppressed total IgE production and induced IL-12 and IFN-gamma production by splenocytes of NC/Nga mice. The additional examination of various neutralization antibodies was performed to elucidate in detail the mechanism of depressed IgE production by strain T120. As a result, it became clear that IL-12 induced by strain T120 increased production of IFN-gamma and total IgE production was mainly controlled by the IFN-gamma. In order to define the cells which produce IL-12 powerfully by this strain, antigen-presenting cells (APCs) such as macrophages and dendritic cells (DCs) were removed from the splenocytes, and the reactivity of these cells to the strain was examined. Induction of IL-12 and IFN-gamma by strain T120 became significantly very low by removal of APCs from splenocytes. Therefore, it was clear that strain T120 acted on APCs and induced production of IL-12. Further, this strain enhanced the production of IL-10 by splenocytes. In in vivo studies, intraperitoneal injection of strain T120 inhibited serum IgE elevation and atopic dermatitis symptoms in NC/Nga mice. These results suggest that an anti-allergic effect of strain T120 depends on the increased production of IL-12 by APCs activated by the strain and following the increased production of IFN-gamma. Further, activation of regulatory T cells by strain T120 may inhibit atopic disease.
Hayashi
Atsushi
A
Science of Functional Foods Graduate School of Agriculture, Shinshu University, 8304 Minamiminowa, Kamiina, Nagano 399-4598, Japan.
Kimura
Makoto
M
Nakamura
Yusaku
Y
Yasui
Hisako
H
D000818:Animals; D002478:Cells, Cultured; D043302:Cultured Milk Products / Q000382:microbiology*; D016207:Cytokines / Q000378:metabolism; D003876:Dermatitis, Atopic / Q000517:prevention & control*; D016984:Enterococcus faecium / Q000502:physiology*; D019344:Lactic Acid / Q000378:metabolism*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008986:Mongolia; D010581:Peyer's Patches / Q000166:cytology / Q000378:metabolism; D013047:Specific Pathogen-Free Organisms; D013154:Spleen / Q000166:cytology / Q000378:metabolism
D016207:Cytokines; D019344:Lactic Acid