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Abstract Decellularization of discarded whole livers and their recellularization with patient‐specific induced pluripotent stem cells (iPSCs) to develop a functional organ is a promising approach to increasing the donor pool. The effect of extracellular matrix (ECM) of marginal livers on iPSC‐hepatocyte differentiation and function has not been shown. To test the effect of donor liver ECM age and steatosis, young and old, as well as no, low, and high steatosis livers, are decellularized. All livers are decellularized successfully. High steatosis livers have fat remaining on the ECM after decellularization. Old donor liver ECM induces lower marker expression in early differentiation stages, compared to young liver ECM, while this difference is closed at later stages and do not affect iPSC‐hepatocyte function significantly. High steatosis levels of liver ECM lead to higher albumin mRNA expression and secretion while at later stages of differentiation expression of major cytochrome (CYP) 450 enzymes is highest in low steatosis liver ECM. Both primary human hepatocytes and iPSC‐hepatocytes show an increase in fat metabolism marker expression with increasing steatosis levels most likely induced by excess fat remaining on the ECM. Overall, removal of excess fat from liver ECM may be needed for inducing proper hepatic function after recellularization.
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Enhanced hepatogenic differentiation of bone marrow derived mesenchymal stem cells on liver ECM hydrogel
Abstract Bone marrow derived mesenchymal stem cells (BM‐MSC) is a promising alternative cell source to primary hepatocytes because of their ability to differentiate into hepatocyte‐like cells. However, their inability to differentiate efficiently and potential to turn into myofibroblasts restrict their applications. This study developed a plate coating from the liver extracellular matrix (ECM) and investigated its ability in facilitating the BM‐MSCs proliferation, hepatic differentiation, and hepatocyte‐specific functions duringin vitroculture. After 28‐day culture, BM‐MSCs on the ECM coating showed hepatocyte‐like morphology, and certain cells took up low‐density lipoprotein. Synthesis of albumin, urea, and anti‐alpha‐fetoprotein, as well as expression of certain hepatic markers, in cells cultured on ECM were higher than cells cultured on non‐coated and Matrigel‐coated plates. mRNA levels of CYP3A4, albumin, CK18, and CYP7A1 in cells on ECM coating were significantly higher than cells cultured on the non‐coating environment. In conclusion, viability and hepatogenic differentiation of BM‐MSCs cultured on both Matrigel and ECM coating were significantly enhanced compared with those cultured on non‐coated plates. Moreover, the liver ECM coating induced additional metabolic functions relative to the Matrigel coating. The liver ECM hydrogel preserves the natural composition, promotes simple gelling, induces efficient stem cell hepatogenic differentiation, and may have uses as an injectable intermedium for hepatocytes. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 829–838, 2018.
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- Award ID(s):
- 1700191
- PAR ID:
- 10050317
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Biomedical Materials Research Part A
- Volume:
- 106
- Issue:
- 3
- ISSN:
- 1549-3296
- Page Range / eLocation ID:
- p. 829-838
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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