The Soil Bacterium Bath Interacts with Human Dendritic Cells to Modulate Immune Function.
| ID: mdl-28293233
The prevalence of inflammatory bowel disease (IBD) has increased in Western countries during the course of the twentieth century, and is evolving to be a global disease. Recently we showed that a bacterial meal of a non-commensal, non-pathogenic methanotrophic soil bacterium, Bath prevents experimentally induced colitis in a murine model of IBD. The mechanism behind the effect has this far not been identified. Here, for the first time we show that , a soil bacterium adheres specifically to human dendritic cells, influencing DC maturation, cytokine production, and subsequent T cell activation, proliferation and differentiation. We characterize the immune modulatory properties of and compare its immunological properties to those of another Gram-negative gammaproteobacterium, the commensal K12, and the immune modulatory Gram-positive probiotic bacterium, GG . induces intermediate phenotypic and functional DC maturation. In a mixed lymphocyte reaction -primed monocyte-derived dendritic cells (MoDCs) enhance T cell expression of CD25, the Î³-chain of the high affinity IL-2 receptor, supports cell proliferation, and induce a T cell cytokine profile different from both K12 and GG. Bath thus interacts specifically with MoDC, affecting MoDC maturation, cytokine profile, and subsequent MoDC directed T cell polarization.