Abstract To investigate the pathogenesis of a congenital form of hepatic fibrosis, human hepatic organoids were engineered to express the most common causative mutation for Autosomal Recessive Polycystic Kidney Disease (ARPKD). Here we show that these hepatic organoids develop the key features of ARPKD liver pathology (abnormal bile ducts and fibrosis) in only 21 days. The ARPKD mutation increases collagen abundance and thick collagen fiber production in hepatic organoids, which mirrors ARPKD liver tissue pathology. Transcriptomic and other analyses indicate that the ARPKD mutation generates cholangiocytes with increased TGFβ pathway activation, which are actively involved stimulating myofibroblasts to form collagen fibers. There is also an expansion of collagen-producing myofibroblasts with markedly increased PDGFRB protein expression and an activated STAT3 signaling pathway. Moreover, the transcriptome of ARPKD organoid myofibroblasts resemble those present in commonly occurring forms of liver fibrosis. PDGFRB pathway involvement was confirmed by the anti-fibrotic effect observed when ARPKD organoids were treated with PDGFRB inhibitors. Besides providing insight into the pathogenesis of congenital (and possibly acquired) forms of liver fibrosis, ARPKD organoids could also be used to test the anti-fibrotic efficacy of potential anti-fibrotic therapies.
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Targeted Delivery of an siRNA/PNA Hybrid Nanocomplex Reverses Carbon Tetrachloride‐Induced Liver Fibrosis
Liver fibrosis is a wound healing process marked by excessive accumulation of extracellular matrix in the liver. A poly(rC)‐binding protein 2 (PCBP2) siRNA that reverses fibrogenesis in activated hepatic stellate cells (HSCs) has been recently discovered. However, targeted delivery of siRNAs to HSCs still remains a daunting challenge. Herein, a new strategy is developed to fabricate a multicomponent nanocomplex using siRNA/peptide nucleic acid (PNA) hybrid instead of chemically conjugated siRNA, thus increasing the scalability and feasibility of the siRNA nanocomplex for animal studies. The nanocomplex is modified with an insulin growth factor 2 receptor ‐specific peptide, which specifically binds to activated HSCs. The siRNA nanocomplex demonstrates a controllable size, high serum stability, and high cellular uptake in activated HSCs in vitro and in vivo. Anti‐fibrotic activity of the siRNA nanocomplex is evaluated in rats with carbon tetrachloride‐induced liver fibrosis. Treatment with the PCBP2 siRNA nanocomplex significantly inhibits the mRNA expressions of PCBP2 and type I collagen in fibrotic liver. The histology study reveals that the siRNA nanocomplex efficiently reduces the protein level of type I collagen and reverses liver fibrosis. The data suggests that the nanocomplex efficiently delivers the siRNA to fibrotic liver and produces a potent anti‐fibrotic effect.
more » « less- PAR ID:
- 10460608
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Therapeutics
- Volume:
- 2
- Issue:
- 8
- ISSN:
- 2366-3987
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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