Role of the human microbiota and probiotics

National Institute Of Allergy And Infectious Diseases

Investigators

Linked publications, trials & patents

Abstract

In FY 2022, we focused on two major projects: First, we investigated a beneficial role of the skin commensal S. epidermidis that is unrelated to previously described immune activation mechanisms, but directly affects skin integrity. Namely, we found that commensal Staphylococcus epidermidis contributes to skin barrier homeostasis by generating protective ceramides, main constituents of the skin's protective barrier. Second, we continued our interest in developing probiotic therapeutics with established underlying molecular mechanisms by following up on our previous discovery that Bacillus produces lipopeptides quench Agr quorum-sensing. We showed that these lipopeptides similarly block the Enterococcus faecalis Agr-homologous system, which we also show is needed for E. faecalis to transgress from the intestine into the bloodstream. Probiotic B. subtilis spores orally administered to mice blocked the initiation of E. faecalis bacteremia via that mechanism.