Liver injury from viral hepatitis, alcohol abuse, and non-alcoholic fatty liver diseases/non-alcoholic steatohepatitis (NAFLD/NASH), among others, promotes deposition of extracellular matrix (ECM) protein by myofibroblasts primarily derived from activated hepatic stellate cells (HSCs), the resident pericytes of the liver3. Here, PROS1 is linked to metabolic dysfunction-associated steatohepatitis.