Biology subjects

Morell, C. M.

Publications and source records attributed to Morell, C. M..

3 recordsLinked to original sources

bioRxiv2025

Mechanical signalling through collagen I regulates cholangiocyte specification and tubulogenesis during liver development

Cholangiocyte dysfunction accounts for a third of liver transplantations, access to which is limited by a shortage of healthy donor organs. A promising alternative is the therapeutic use of human induced pluripotent stem cell (hiPSC)-derived cholangiocytes. However, the use of hiPSCs is impeded by a lack of knowledge regarding intrahepatic cholangiocyte development, limiting the generation of fully functional cells. In this study, we generate hiPSC-derived tubular cholangiocytes using an approach based in synthetic hydrogels. These hydrogels exert control over stiffness and extracellular matrix (ECM) composition and stability, allowing us to address a critical gap in understanding cholangiocyte development. Our findings reveal that stable collagen I functionalisation, particularly on a soft substrate, enhances cholangiocyte differentiation, largely irrespective of substrate stiffness. Furthermore, high collagen I stability on a soft substrate suppresses hepatic identity whilst promoting biliary identity and duct morphogenesis. Our findings highlight the importance of collagen I mechanical signalling in regulating hepatoblast fate determination. Overall, we propose a mechanism by which the ECM modulates cholangiocyte and bile duct development and present a scalable platform for future clinical applications in the understanding and treatment of cholangiopathies.

developmental biology↗

bioRxiv2024

Novel 3D Approach to Model Non-Alcoholic Fatty Liver Disease using human Pluripotent Stem Cells

Background and aimsNon-alcoholic fatty liver disease (NAFLD) is a major health care challenge and new therapies are urgently needed. However, the mechanisms underlying disease remain to be understood. Indeed, studying NAFLD remains challenging due to the lack of model systems recapitulating the different aspects of the human pathology. Human induced pluripotent stem cells (hiPSCs) offer a unique opportunity to address this limitation since they can be differentiated into large quantity of liver cells. Here, we took advantage of hiPSCs to develop a multi-cellular platform mimicking the complex interplays involved in NAFLD progression. MethodshiPSCs-derived hepatocyte like cells (HLCs), cholangiocytes, stellate cells, and macrophages were co-cultured in a collagen-based 3D system to reproduce the liver microenvironment. Fatty acid treatments led to a NAFLD phenotype involving cell-cell interactions which were investigated by transcriptomic and functional analyses. ResultsHepatic cells were grown up to 4weeks in 3D, retaining key functions and markers. Importantly, co-cultured cells spontaneously reorganised into physiologically relevant connections: HLCs arranged around biliary structures, which established contacts with stellate cells, while macrophages organised around HLCs. Fatty acid treatments induced steatosis and lipotoxicity in HLCs. Furthermore, fat-laden HLCs prompted a non-parenchymal cells response altering tissue architecture. ConclusionsOur multicellular platform provides a new approach to model interactions between human hepatic cells during NAFLD progression. Such approach has the potential to investigate the sequential events driving chronic liver diseases, including hepatocellular injury, inflammation and fibrosis. Furthermore, our system provides a unique and urgently needed tool to investigate the molecular mechanisms associated with NAFLD and ultimately to validate new targets for therapeutics development. List of abbreviationsCOs, cholangiocytes organoids; FFA, free fatty acids; hiPSCs, human induced pluripotent stem cells; HLCs, hepatocyte like cells; HSCs, hepatic stellate cells; M0, hiPSCs-derived macrophages; NAFLD, non-alcoholic fatty liver disease; NPCs, non-parenchymal cells; OA, oleic acid; PA, palmitic acid.

cell biology↗

bioRxiv2022

Generation of functional hepatocytes by forward programming with nuclear receptors

Production of large quantities of hepatocytes remains a major challenge for a number of clinical applications in the biomedical field. Directed differentiation of human pluripotent stem cells (hPSC) into hepatocyte-like cells (HLCs) provides an advantageous solution and a number of protocols have been developed for this purpose. However, these methods usually follow different steps of liver development in vitro which is time consuming and requires complex culture conditions. In addition, HLCs lack the full repertoire of functionalities characterising primary hepatocytes. Here, we explore the interest of forward programming to generate hepatocytes from hPSCs and to bypass these limitations. This approach relies on the overexpression of 3 hepatocyte nuclear factors (HNF1A, HNF6 and FOXA3) in combination with different nuclear receptors expressed in the adult liver using the OPTi-OX platform. Forward programming allows for the rapid production of hepatocytes (FoP-Heps) with functional characteristics using a simplified process. We also uncovered that the overexpression of nuclear receptors such as RORc can enhance specific functionalities of FoP-Heps thereby validating its role in lipid/glucose metabolism. Together, our results show that forward programming could offer a versatile alternative to direct differentiation for generating hepatocytes in vitro.

developmental biology↗