MASH Background Confers Enhanced Disease Susceptibility and Acetaminophen Toxicity in iPSC‐Derived Liver Organoids

Liver Organoids: From Disease Modelling to Regenerative Medicine

This review systematically summarises current fabrication strategies, disease‐modelling utilities and regenerative potentials of liver organoids, alongside the major challenges and future directions.

Behaviour of iPSC-Derived and Donor-Derived Hepatic Stellate Cells in Organoid Cultures Is Highly Variable and Contributes to Fibrotic Outcome

Hepatic stellate cells (HSCs) are central drivers of liver fibrosis, yet their heterogeneity is often overlooked in human liver organoid models. Here, we investigated how HSC-intrinsic variability influences fibrotic phenotypes in multicellular liver organoids using induced pluripotent stem cell-derived HSCs (iHSCs) and primary HSCs (pHSCs). iHSCs derived from two different iPSC lines exhibited distinct differentiation phenotypes towards iHSCs. Consistently, co-culture of the hepatocyte-like cell line HepaRG with these two iHSC populations generated organoids with distinct fibrotic and hepatic features. BJ1-iHSC/HepaRG organoids contained an approximately 2.9-fold higher proportion of CYP3A4-positive cells, whereas Sigma-iHSC/HepaRG organoids showed around a 4-fold higher percentage of Sirius red-positive area. Single-cell RNA analysis further showed that the two iHSC populations differed in cell cycle distribution, HSC-related signatures, extracellular matrix-associated pathways, and matrisome enrichment. Similarly, human pHSCs cultured as organoids with HepaRG showed marked donor-dependent differences at baseline and after single acetaminophen, repeated thioacetamide or transforming growth factor beta treatment. Together, our findings suggest that HSC heterogeneity, whether iPSC-derived or donor-derived, is an important factor in fibrotic output and response variability in human liver organoid models and should be considered in model design, interpretation and comparison between studies.

Human stem cell-derived hepatic cells recapitulate polygenic risk in MASLD development and highlight CD36 as a key mediator.

Several genetic variants have been identified that impact outcomes in patients with metabolic dysfunction-associated steatohepatitis (MASH), but cellular platforms to identify molecular targets for treatment remain scarce. This study aims to employ a polygenic risk score for hepatic fat content (PRS-HFC) in a human-based in vitro model to identify potential druggable targets related to a genetic risk for MASH. Ninety-two human skin-derived precursor (hSKP) cell lines were genotyped and classified according to their PRS-HFC. Per risk category, five cell lines were selected and differentiated to hepatic progenitor-like cells (hSKP-HPCs) before being exposed to MASH-related triggers or control medium. Lipid accumulation, fatty acid uptake, generation of oxidative stress, secretion of inflammatory mediators, and alterations of the transcriptome were assessed. Potential drug targets were modulated using siRNA. hSKP-HPCs displayed a positive correlation between lipid accumulation and PRS-HFC, both in the control and 'MASH' condition. hSKP-HPCs with high PRS-HFC exhibited increased secretion of interleukin 6 and enhanced fatty acid uptake. Bulk RNA barcoding and sequencing revealed distinct gene expression profiles depending on genetic predisposition and predicted increased CD36-signalling as potential upstream regulator thereof. Silencing of CD36 effectively reduced lipid accumulation in cultures with high PRS-HFC and attenuated expression of genes related to de novo lipogenesis, lipolysis and inflammation. hSKP-HPCs recapitulate the effect of the PRS-HFC on lipid accumulation and inflammation. CD36 appeared to at least partially mediate these effects, and its silencing further substantiated its role in conferring high genetic risk for MASH, highlighting CD36 as a potential therapeutic target for genetically-driven MASH. ABBREVIATIONS.

Leveraging IGF signaling to improve the spatial organization and regenerative potential of iPSC-derived vascularized liver organoids

Vascularized liver organoids are developed by integrating human induced pluripotent stem cell (iPSC)–derived hepatoblasts and endothelial cells into decellularized scaffolds functionalized with an anti-CD31 aptamer–based vascular coating agent (VCA) to establish a comprehensive framework for generating physiologically relevant liver tissues from iPSCs and demonstrate the utility of spatial transcriptomics for uncovering regenerative mechanisms.

From liver organoids to regulatory platforms for precision hepatology: Advances and challenges

This Review summarizes recent technological progress, discusses strategies to improve regulatory fidelity and functional benchmarking, and outlines future directions toward developing liver organoids as more reliable platforms for disease modeling and precision hepatology.

Comparison of hiPSC-derived hepatic organoids and liver-on-a-chip systems reveal microenvironment-driven maturation