Figure 2.

Pathophysiology of PSC. Against the background of a genetic susceptibility, specific components of microbiome or metabolic products can trigger an exaggerated immune response from cholangiocytes. Alternatively (or in addition), the gut dysbiosis is responsible for altered metabolic function of the gut microbiome with subsequent changes of the bile acid pool or an increased intestinal permeability. Treatment with vancomycin (or potentially fecal microbiota transplantation) shifts the microbiome toward, e.g., Proteobacteria with subsequent effects on the production of secondary bile acids. This affects the bile acid pool and influences favorably cholangiocyte biology. PSC, primary sclerosing cholangitis.