IL1B and Barrett esophagus: Bacteria are responsible for much of bile acid metabolism, including bile acid deconjugation via bile salt hydrolase as well as the conversion of primary to secondary bile acids, and bile acids can shape bacterial composition via bactericidal and other effects.5 In the L2-IL1B model, mice raised in a germ-free setting have reduced development of BE and dysplasia,6 suggesting that bacteria are important co-factors in the development of EAC.