You are hereFebruary 7, 2020 | ESCs/iPSCs
Enhanced Disease Modeling and Treatment Opportunities with Human ESC-Derived Expandable Hepatic Organoids
Review of “Human ESC-derived expandable hepatic organoids enable therapeutic liver repopulation and pathophysiological modeling of alcoholic liver injury” from Cell Research by Stuart P. Atkinson
The establishment of hepatic organoids from primary liver tissues [1, 2] represented a potentially massive breakthrough in liver disease modeling and transplantation therapy; however, the robust production of organoids for large-scale applications remained a challenging proposal. As a response, many laboratories developed the means to generate hepatic organoids from human pluripotent stem cells (hPSCs) with varying levels of success; the most advanced protocols, which still suffer from certain drawbacks, employed co-culture of hPSC-derived hepatic endoderm cells with liver-associated, non-parenchymal cells  or differentiation under solely three-dimensional (3D) culture conditions .
To circumvent remaining problems, researchers led by Yunfang Wang (Beijing Institute of Health Service and Transfusion Medicine/Beijing Tsinghua Chang Gung Hospital, China) developed a new means to generate what they call “human embryonic stem cell-derived expandable hepatic organoids,” or hEHOs, using a uniquely-defined serum-free culture media and 3D feeder-free culture conditions . Wang et al. hope that their protocol will provide the means to generate powerful in vitro models for mechanistic studies, biomarker screening, and the development of novel treatment for a range of liver diseases and disorders.
The generation of hEHOs began by cultivating hESCs in traditional monolayer culture and inducing definitive endoderm formation using Activin A and Wnt3A, then prompting hepatic specification using BMP4 and FGF2, and then moving to 3D culture conditions in the presence of N2, B27, Nicotinamide, Gastrin, N-Acetylcysteine, EGF, Wnt3a, R-Spondin 1, A83-01, and Forskolin. These culture conditions allowed for the rapid growth of hollow spherical structures within two days and then the maturation of these structures into large 3D organoids within ten days. Resultant hEHOs resembled previously reported human adult liver-derived hepatic organoids  and could be expanded for around 20 passages, thereby enabling the generation of up to 1018 cells after only five months. Furthermore, hEHOs could be re-established from single hEHO-derived cells, which maintained the features of bipotential liver stem/progenitor cells with the ability to differentiate into functional hepatocytes or cholangiocytes – an ability yet to be reported in other similar studies.
Finally, the authors formed organoids by combining human fetal liver mesenchymal cells with hEHO cells to allow for the successful modeling of alcoholic liver disease, the primary cause of liver-related mortality in Western countries, also for the first time. Encouragingly, the study reported that ethanol treatment provoked disease-associated pathophysiologic changes, which included oxidative stress generation, inflammatory mediator release, and fibrosis, suggesting this approach as an exciting new means to study liver disease development, identify biomarkers, and explore possible treatment options, which include cell/tissue transplantation.
For more on the promise of stem cell-derived human organoids, stay tuned to the Stem Cells Portal!
- Huch M, Gehart H, van Boxtel R, et al., Long-Term Culture of Genome-Stable Bipotent Stem Cells from Adult Human Liver. Cell 2015;160:299-312.
- Hu H, Gehart H, Artegiani B, et al., Long-Term Expansion of Functional Mouse and Human Hepatocytes as 3D Organoids. Cell 2018;175:1591-1606.e19.
- Takebe T, Sekine K, Enomura M, et al., Vascularized and functional human liver from an iPSC-derived organ bud transplant. Nature 2013;499:481-484.
- Guan Y, Xu D, Garfin PM, et al., Human hepatic organoids for the analysis of human genetic diseases. JCI Insight 2017;2.
- Wang S, Wang X, Tan Z, et al., Human ESC-derived expandable hepatic organoids enable therapeutic liver repopulation and pathophysiological modeling of alcoholic liver injury. Cell Research 2019;29:1009-1026.