ANO1 is therefore indispensable for the formation of a protective HCO3− umbrella on the apical surface of human cholangiocytes.25–27 Glycine-conjugated bile acid influx as a result of an impaired apical biliary HCO3- umbrella has been shown to induce cholangiocyte damage,26,27 which probably contributes to the progressive bile duct destruction found in immune-mediated cholangiopathies such as PBC and PSC.28–30,33,34,58,59 Loss of expression of ANO1 resulted in increased apoptosis in H69 cholangiocytes when exposed to glycine-conjugated chenodeoxycholic acid. This evidence concerns the gene ANO1 and primary biliary cholangitis.