Human hepatocytes express important transport proteins that are responsible for the uptake and removal of organic anions from the blood. These proteins are members of the organic anion-transporting polypeptide (OATP) family and are essential for proper liver function. OATPs are encoded by the SLC21 gene family and contain 12 transmembrane alpha-helices and are primarily expressed in the liver. The OATP family transports endogenous substrates like bile salts and steroid hormones as well as exogenous molecules like anticancer drugs and imaging agents.
