Abstract
Chemically induced liver progenitors (CLiPs) have promising applications in liver regenerative medicine. Three-dimensional (3D) structures generated from liver progenitor cells possess wide applications in cell transplantation, disease model, and drug testing. Here, we report on the spontaneous formation of 3D cystic structures comprising maturing rat CLiPs on gelatin-coated dishes. Our 3D cysts contained Alb+/+CK19+/− and Ck19+/+Alb+/− cells. These cell types gradually diverged into specialized mature cells, as demonstrated by the expression of mature biliary markers (Cftr, Ae2, and Aqp1) and hepatic markers (Alb and Mrp2). The 3D cysts also expressed functional multidrug resistance protein 1 (Mdr1), as indicated by epithelial efflux of rhodamine. Furthermore, we observed bile canaliculi functions between hepatocytes and cholyl-lysyl-fluorescein extrusions, indicating that the functional characteristics of 3D cysts and active bile salt export pump (Bsep) transporters were intact. Thus, our study revealed a natural characteristic of rat CLiPs to spontaneously form 3D cystic structures accompanied with cell maturation in vitro, offering a platform for studies of liver development and drug screening.
Highlights
Several studies have shown that in vivo hepatocytes can transform into proliferative bipotent liver progenitor cells (LPCs) following chronic liver injury [1,2,3,4]
A recent study in Japan shows that the YAC cocktail of the three small molecules Y-27632, A-83-01, and CHIR99021 can convert mature rodent hepatocytes into proliferative bipotent cells in vitro which were previously identified as chemically induced liver progenitors (CLiPs) [6]
As previously reported by Katsuda et al, passaged CLiPs are generally cultured on collagen-coated dishes in reprogramming medium containing 5% fetal bovine serum (FBS) for the first day after seeding, and without FBS thereafter [6]
Summary
Several studies have shown that in vivo hepatocytes can transform into proliferative bipotent liver progenitor cells (LPCs) following chronic liver injury [1,2,3,4]. In China too, researchers have successfully converted the primary human hepatocytes into bipotent LPCs by using the three small molecules, Y-27632, A-83-01, and CHIR99021, and two growth factors, HGF and epidermal growth factor [8]. Those chemically induced LPCs have the potential to differentiate into hepatic or cholangiocytic cells in vitro. These cells were shown to extensively repopulate chronically injured liver tissues in vivo [6, 7] and can serve as a suitable model to study the host interactions with HBV and antiviral therapies [8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
