Engineering of human liver progenitor-like cells for a new exosomal thrapy of liver fibrosis

Background: Chemically induced liver progenitor cells (CLiPs), generated from mature hepatocytes by adding small molecules in the medium, are expected to be useful to overcome liver diseases (Cell Stem Cell, 2017; J Gastroenterol, 2022). However, the long-term maintenance of hCLiPs with optimal functionality was still challenging (Elife, 2019). In addition, human mature hepatocytes, the source of hCLiPs, is limited resources. Here, we examined whether the therapeutic potency of hCLiP for liver fibrosis and how we culture functionally stable hCLiPs in large scales.
Methods: Intraperitoneal administration of CCl4 was conducted twice a week for 8 weeks. hCLiPs/vehicles were intrasplenically transplanted into the mice. In addition, we investigated the efficient methods for the immortalization of hCLiPs.
Results: The fibrosis level was pathologically improved in hCLiPs transplantation groups with reasonable changes in gene expressions. In vitro, protein levels of αSMA in the activated hepatic stellate cells were downregulated by the exposure to hCLiP-derived extracellular vesicles (EVs). Immortalized hCLiPs secreted human alubumin as high as hCLiPs. In addition, our preliminary results suggested that the transplantation of immortalized hCLiPs also improved liver fibrosis in mice.
Conclusion: hCLiPs and hCLiP-derived EVs had the therapeutic potential for liver fibrosis. We succeeded in making immortalizing hCLiPs and stably collecting a large amount of EVs using immortalized hCLiPs.