Dong-Hun Woo1, Suel-Kee Kim1,2, Hee-Joung Lim1, Jeonghoon Heo3, Hyung Soon Park4, Gum-Yong Kang4, Sung-Eun Kim1, Hyun-Ju You1, Daniel J. Hoeppner2, Youngchul Kim5, Heechung Kwon6, Tae Hyun Choi7, Joo Hee Lee8, Su Hee Hong7, Kang Won Song9, Eun-Kyung Ahn3, Josh G. Chenoweth2, Paul J. Tesar2,10, Ronald D.G. McKay2, Jong-Hoon Kim1*
1 Laboratory of Stem Cell Biology, Division of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713, Republic of Korea
2 Laboratory of Molecular Biology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
3 Department of Molecular Biology and Immunology, College of Medicine, Kosin University, Busan 602-703, Republic of Korea
4 Probiond Co., Ltd., Information center for admissions, Konkuk University, Seoul, 143-170, Republic of Korea
5 Department of Surgery, College of Medicine, Korea University, Seoul 136-705, Republic of Korea
6 Division of Radiation Cancer Research, Korea Institute of Radiological & Medical Sciences, Seoul 139-706, Republic of Korea
7 Radiopharmaceuticals and Laboratory of Nuclear Medicine, Korea Institute of Radiological and Medical Sciences, Seoul 139-706, Republic of Korea
8 Division of Radiation Cancer Research, Korea Institute of Radiological & Medical Sciences, Seoul 139-706, Republic of Korea
9 Department of Pathology, National Cancer Center, Gyeonggi-do 410-769, Republic of Korea
10 Department of Genetics, Center for Stem Cell and Regenerative Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
* Corresponding author: Jong-Hoon Kim, Ph. D., West Building/Room 304, College of Life Sciences and Biotechnology, Science Campus, Korea University, 1, Anam-dong 5-ga, Sungbuk-goo, Seoul 136-713, Korea
Background & Aims
Many studies of embryonic stem cells have investigated direct cell replacement of damaged tissues, but little is known how donor cell-derived signals affect host tissue regeneration. We investigated the direct and indirect roles of human embryonic stem cell-derived cells in liver repair in mice.
To promote the initial differentiation of human embryonic stem cells into mes-endoderm, we activated the β-catenin signaling pathway with lithium; cells were then further differentiated into hepatocyte-like cells. The differentiated cells were purified by indocyanine green staining and laser microdissection and characterized by immunostaining, PCR, biochemical function, electron microscopy, and transplantation analyses. To investigate indirect effects of these cells, secreted proteins (secretomes) were analyzed by a label-free quantitative mass spectrometry. Carbon tetrachloride was used to induce acute liver injury in mice; cells or secreted proteins were administered by intrasplenic or intraperitoneal injection, respectively.
The differentiated hepatocyte-like cells had multiple features of normal hepatocytes, engrafted efficiently into mice, and continued to have hepatic features; they promoted proliferation of host hepatocytes and revascularization of injured host liver tissues. Proteomic analysis identified proteins secreted from these cells that might promote host tissue repair. Injection of the secreted proteins into injured livers of mice promoted significant amounts of tissue regeneration, without cell grafts.
Hepatocyte-like cells derived from human embryonic stem cells contribute to recovery of injured liver tissues in mice, not only by cell replacement but also by delivering trophic factors that support endogenous liver regeneration.
Keywords: hES cells, hepatitis, mouse model, stem cell therapy