Intrahepatic bile duct tissue engineering utilizing liver matrix and 3D bioprinting

Currently the only treatment for primary sclerosing cholangitis is liver transplantation, but there remains a critical shortage of donor organs. Liver tissue engineering aims to provide viable alternative sources of donor tissue for those facing end stage liver disease. However, the majority of liver tissue engineering approaches do not involve regenerating the intrahepatic bile ducts (IHBD), an essential component if the engineered tissue is to be a transplant alternative. Major barriers facing IHBD tissue engineering are associated with its detailed hierarchical structure. The goal of this proposal is to engineer an organized ductular network by controlling both the biochemical and architectural environment of biliary epithelial cells (e.g. cholangiocytes). Our preliminary work has shown that mouse cholangiocytes display in vitro morphogenic capability into branching networks when cultured in liver decellularized extracellular matrix (dECM), however the structures formed are highly unorganized. We aim to use 3D printing to guide the growth of these ductular networks as well as investigate the use of dECM obtained from liver tissue after a partial hepatectomy to further enhance the regenerative potential of dECM. Partial hepatectomy leads to significant ECM remodeling and cellular proliferation. We hypothesize that the ECM harvested from a regenerating liver will lead to a more favorable morphogenic response of cultured cholangiocytes. We then propose to control this process by using 3D bioprinting to spatially pattern cells and ECM in a fashion that will lead to organized hierarchical ductal structures reminiscent of native liver tissue.