Abstract: Liver diseases caused by drugs, toxins, metabolic disorders, or pathogens can progress to liver failure, a life-threatening condition requiring transplantation. However, the demand for donor livers far exceeds the available supply, leaving many patients on waiting lists. As a result, many patients die while awaiting a transplant. Induced pluripotent stem cell (iPSC)-derived hepatocyte therapies offer a promising solution to address these challenges. Using iPSC technology, we developed a forward programming hepatocytes (FoP-Heps). These hepatocytes were culture in 3D suspension system to form hepatocyte organoids (HepO) which can be rapidly produced in large quantities. To evaluate their therapeutic potential, we investigated the engraftment, survival, safety, and functionality of HepO in vivo using various mouse models of liver injury, including the CCl4 model. At a later stage, the engraftment of HepO will be investigated in transplant-declined human livers ex vivo to confirm its feasibility for therapeutic application. Histological analyses confirmed the successful engraftment of HepO in vivo as single cells or cell clusters in various mouse tissues. We demonstrated that Hep organoids can survive for several weeks, as evidenced by the preserved cellular and nuclear integrity of the transplanted cells. HepO retained the expression of key hepatocyte markers, including human albumin, HNF-4α, and AAT. Notably, human albumin was expressed within the cytoplasm and secreted in the mouse bloodstream, highlighting functional protein secretion. Our findings demonstrate the robust engraftment of HepO while maintaining key human hepatocyte markers and functional characteristics. Their sustained survival over time represents a favourable feature for ensuring an adequate duration of the cell therapeutic effect. The secretion of albumin into the mouse circulation further reinforces their functionality in vivo. Altogether, these capabilities highlight the promising therapeutic potential of HepO for future transplantation into the livers of patients. Finally, we anticipate that this work will pave the way for the use of iPSC-derived FoP-Heps as a bridge therapy for patients awaiting liver transplantation and as a long-term solution to support liver regeneration in patients with chronic liver diseases.
Funding Source: This work was partly funded by the Wellcome Leap HOPE program
