A multicellular liver organoid model for investigating hepatitis C virus infection and non-alcoholic fatty liver disease progression

Background and Aims: HCV infection can be successfully managed with antiviral therapies; however, progression to chronic liver disease states, including NAFLD, is common. There is currently no reliable in vitro model for investigating host–viral interactions underlying the link between HCV and NAFLD; although liver organoids (LOs) show promise, they currently lack non-parenchymal cells, which are key to modeling disease progression. Approach and Results: Here, we present a novel, multicellular LO model using a co-culture system of macrophages and LOs differentiated from the same human pluripotent stem cells (PSCs). The co-cultured macrophages shifted towards a Kupffer-like cell type, the liver-resident macrophages present in vivo, providing a suitable model for investigating NAFLD pathogenesis. With this multicellular Kupffer-like cell-containing LO (Kp-LO) model, we found that HCV infection led to lipid accumulation in LOs by upregulating host lipogenesis, which was more marked with macrophage co-culture. Reciprocally, long-term treatment of LOs with fatty acids (FAs) upregulated HCV amplification and promoted inflammation and fibrosis. Notably, in our Kp-LO model, the effects of three drugs for NASH that have reached phase 3 clinical trials exhibited consistent results with the clinical outcomes. Conclusions: Taken together, we introduced a multicellular LO model consisting of hepatocytes, Kupffer-like cells, and HSCs, which recapitulated host–virus intercommunication and inter-cellular interactions. With this novel model, we present a physiologically relevant system for the investigation of NAFLD progression in HCV patients. Export