Oral administration of Lactobacillus plantarum NRIC0380 suppresses IgE production and induces CD4(+)CD25(+)Foxp3(+) cells in vivo.

The influence of lactic acid bacteria (LAB) on CD4(+)Foxp3(+) cells has not been investigated, although it has been reported that CD4(+)Foxp3(+) cells might be involved in the inhibition of allergic symptoms. Hence we examined the effect of orally administered LAB on CD4(+)Foxp3(+) generation. Oral administration of Lactobacillus plantarum NRIC0380 significantly inhibited antigen-specific IgE production and enhanced the Th1 response, as some other strains reported in previous studies. The ratio of CD4(+)CD25(+)Foxp3(+) cells in whole CD4(+) cells was significantly higher in both Peyer's patch and the spleen of mice that had been fed with LAB than in the control mice.