Bifidobacteria and Lactobacilli Exhibited Different Mitogenic Activity on Murine Splenocytes

Forty-one strains of Bifidobacterium and Lactobacillus were tested for their ability to induce the proliferation of murine splenocytes using the MTT assay. The tested bifidobacteria induced the apparent proliferation of the murine splenocytes in a strain-dependent manner, while non of the tested lactobacilli showed any mitogenic activity. The bifidobacteria from allergic infants stimulated the proliferation of murine splenyoctes more than those from healthy subjects. On the otherhand, no significant differences were observed in the ability among the selected bifidobacteria and lactobacilli to alter Concanavalin A stimulated proliferation of murine splenyocytes. These results suggest that lactobacilli and bifidobacteria may, at least partly, posses a different potential in the way by which they can affect human immune responses.