Comparison of hepatic-like cell production from human embryonic stem cells and adult liver progenitor cells: CAR transduction activates a battery of detoxification genes

iPSC-derived cells for whole liver bioengineering

Liver bioengineering stands as a prominent alternative to conventional hepatic transplantation. Through liver decellularization and/or bioprinting, researchers can generate acellular scaffolds to overcome immune rejection, genetic manipulation, and ethical concerns that often accompany traditional transplantation methods, in vivo regeneration, and xenotransplantation. Hepatic cell lines derived from induced pluripotent stem cells (iPSCs) can repopulate decellularized and bioprinted scaffolds, producing an increasingly functional organ potentially suitable for autologous use. In this mini-review, we overview recent advancements in vitro hepatocyte differentiation protocols, shedding light on their pivotal role in liver recellularization and bioprinting, thereby offering a novel source for hepatic transplantation. Finally, we identify future directions for liver bioengineering research that may allow the implementation of these systems for diverse applications, including drug screening and liver disease modeling.

Regulation of CAR and PXR Expression in Health and Disease

Pregnane X receptor (PXR, NR1I2) and constitutive androstane receptor (CAR, NR1I3) are members of the nuclear receptor superfamily that mainly act as ligand-activated transcription factors. Their functions have long been associated with the regulation of drug metabolism and disposition, and it is now well established that they are implicated in physiological and pathological conditions. Considerable efforts have been made to understand the regulation of their activity by their cognate ligand; however, additional regulatory mechanisms, among which the regulation of their expression, modulate their pleiotropic effects. This review summarizes the current knowledge on CAR and PXR expression during development and adult life; tissue distribution; spatial, temporal, and metabolic regulations; as well as in pathological situations, including chronic diseases and cancers. The expression of CAR and PXR is modulated by complex regulatory mechanisms that involve the interplay of transcription factors and also post-transcriptional and epigenetic modifications. Moreover, many environmental stimuli affect CAR and PXR expression through mechanisms that have not been elucidated.

Derivation and applications of human hepatocyte-like cells

Human hepatocyte-like cells (HLCs) derived from human pluripotent stem cells (hPSCs) promise a valuable source of cells with human genetic background, physiologically relevant liver functions, and unlimited supply. With over 10 years’ efforts in this field, great achievements have been made. HLCs have been successfully derived and applied in disease modeling, toxicity testing and drug discovery. Large cohorts of induced pluripotent stem cells-derived HLCs have been recently applied in studying population genetics and functional outputs of common genetic variants in vitro. This has offered a new paradigm for genome-wide association studies and possibly in vitro pharmacogenomics in the nearly future. However, HLCs have not yet been successfully applied in bioartificial liver devices and have only displayed limited success in cell transplantation. HLCs still have an immature hepatocyte phenotype and exist as a population with great heterogeneity, and HLCs derived from different hPSC lines display variable differentiation efficiency. Therefore, continuous improvement to the quality of HLCs, deeper investigation of relevant biological processes, and proper adaptation of recent advances in cell culture platforms, genome editing technology, and bioengineering systems are required before HLCs can fulfill the needs in basic and translational research. In this review, we summarize the discoveries, achievements, and challenges in the derivation and applications of HLCs.

Hepatitis C virus: Morphogenesis, infection and therapy

Hepatitis C virus (HCV) is a major cause of liver diseases including liver cirrhosis and hepatocellular carcinoma. Approximately 3% of the world population is infected with HCV. Thus, HCV infection is considered a public healthy challenge. It is worth mentioning, that the HCV prevalence is dependent on the countries with infection rates around 20% in high endemic countries. The review summarizes recent data on HCV molecular biology, the physiopathology of infection (immune-mediated liver damage, liver fibrosis and lipid metabolism), virus diagnostic and treatment. In addition, currently available in vitro, ex vivo and animal models to study the virus life cycle, virus pathogenesis and therapy are described. Understanding of both host and viral factors may in the future lead to creation of new approaches in generation of an efficient therapeutic vaccine.

Patient-specific hepatocyte-like cells derived from induced pluripotent stem cells model pazopanib-mediated hepatotoxicity

Idiosyncratic drug-induced hepatotoxicity is a major cause of liver damage and drug pipeline failure, and is difficult to study as patient-specific features are not readily incorporated in traditional hepatotoxicity testing approaches using population pooled cell sources. Here we demonstrate the use of patient-specific hepatocyte-like cells (HLCs) derived from induced pluripotent stem cells for modeling idiosyncratic hepatotoxicity to pazopanib (PZ), a tyrosine kinase inhibitor drug associated with significant hepatotoxicity of unknown mechanistic basis. In vitro cytotoxicity assays confirmed that HLCs from patients with clinically identified hepatotoxicity were more sensitive to PZ-induced toxicity than other individuals, while a prototype hepatotoxin acetaminophen was similarly toxic to all HLCs studied. Transcriptional analyses showed that PZ induces oxidative stress (OS) in HLCs in general, but in HLCs from susceptible individuals, PZ causes relative disruption of iron metabolism and higher burden of OS. Our study establishes the first patient-specific HLC-based platform for idiosyncratic hepatotoxicity testing, incorporating multiple potential causative factors and permitting the correlation of transcriptomic and cellular responses to clinical phenotypes. Establishment of patient-specific HLCs with clinical phenotypes representing population variations will be valuable for pharmaceutical drug testing.

One Standardized Differentiation Procedure Robustly Generates Homogenous Hepatocyte Cultures Displaying Metabolic Diversity from a Large Panel of Human Pluripotent Stem Cells

Human hepatocytes display substantial functional inter-individual variation regarding drug metabolizing functions. In order to investigate if this diversity is mirrored in hepatocytes derived from different human pluripotent stem cell (hPSC) lines, we evaluated 25 hPSC lines originating from 24 different donors for hepatic differentiation and functionality. Homogenous hepatocyte cultures could be derived from all hPSC lines using one standardized differentiation procedure. To the best of our knowledge this is the first report of a standardized hepatic differentiation procedure that is generally applicable across a large panel of hPSC lines without any adaptations to individual lines. Importantly, with regard to functional aspects, such as Cytochrome P450 activities, we observed that hepatocytes derived from different hPSC lines displayed inter-individual variation characteristic for primary hepatocytes obtained from different donors, while these activities were highly reproducible between repeated experiments using the same line. Taken together, these data demonstrate the emerging possibility to compile panels of hPSC-derived hepatocytes of particular phenotypes/genotypes relevant for drug metabolism and toxicity studies. Moreover, these findings are of significance for applications within the regenerative medicine field, since our stringent differentiation procedure allows the derivation of homogenous hepatocyte cultures from multiple donors which is a prerequisite for the realization of future personalized stem cell based therapies.

Hepatocyte-like cells derived from induced pluripotent stem cells

The discovery that coordinated expression of a limited number of genes can reprogram differentiated somatic cells to induced pluripotent stem cells (iPSC) has opened novel possibilities for developing cell-based models of diseases and regenerative medicine utilizing cell reprogramming or cell transplantation. Directed differentiation of iPSCs can potentially generate differentiated cells belonging to any germ layer, including cells with hepatocyte-like morphology and function. Such cells, termed iHeps, can be derived by sequential cell signaling using available information on embryological development or by forced expression of hepatocyte-enriched transcription factors. In addition to the translational aspects of iHeps, the experimental findings have provided insights into the mechanisms of cell plasticity that permit one cell type to transition to another. However, iHeps generated by current methods do not fully exhibit all characteristics of mature hepatocytes, highlighting the need for additional research in this area. Here we summarize the current approaches and achievements in this field and discuss some existing hurdles and emerging approaches for improving iPSC differentiation, as well as maintaining such cells in culture for increasing their utility in disease modeling and drug development.

[Induced pluripotent stem cells: a new paradigm to study human tissues]

Induced pluripotent stem cells (iPSCs) are obtained by reprogramming differentiated cells through forced expression of four embryonic transcription factors. The discovery of this technology, able to transform a differentiated cell into a pluripotent cell, has profoundly shifted the paradigm of the concept of cell identity, since it is now possible to obtain in vitro any cell type from an initial sample of skin or blood cells from a healthy volunteer or patient. Applications of iPSCs are exceedingly large, and comprise the in vitro modeling of normal or pathological tissues, including for massive drug screening. They also open new therapeutic avenues in the field of regenerative medicine.

Cultured Cells from the Human Oocyte Cumulus Niche Are Efficient Feeders to Propagate Pluripotent Stem Cells

Pluripotency is at the crossroads of stem cell research and biology of reproduction. The mature metaphase II oocyte contains the key factors for pluripotency induction and maintenance as assessed by its capacity to reprogram somatic nuclei. The cumulus cells (CCs) niche that surrounds the oocyte is crucial for its maturation and presumably for the oocyte to acquire its competence to confer pluripotency. In this study, we examined whether cells cultured from the human mature metaphase II oocyte CC niche (hCC) could be used as feeders for the propagation of human induced pluripotent stem cells. The induced pluripotent (iPS) cells cultured on hCC (hCC-iPS) were assessed for their pluripotency potential by their expression of pluripotency-associated genes such as Oct4, Nanog, and TRA1-60 and their competence to differentiate into the three germ layers in vitro (embryoid bodies) as well as in vivo (teratoma formation). We show that not only the hCC-iPS cells maintained their pluripotency potential, but they also exhibited much better self-renewal performance in terms of proliferation rate compared to the same cells cultured on human foreskin fibroblast (hFF) feeders (hFF-iPS). A comparative gene expression profile study of hCC and hFF revealed significant differences (P < 0.05) in expression of cellular matrix components and an upregulation in hCC of genes known to be important players in cell proliferation such as interleukin 6 gene (IL6).

In vitro culture of isolated primary hepatocytes and stem cell-derived hepatocyte-like cells for liver regeneration

Various liver diseases result in terminal hepatic failure, and liver transplantation, cell transplantation and artificial liver support systems are emerging as effective therapies for severe hepatic disease. However, all of these treatments are limited by organ or cell resources, so developing a sufficient number of functional hepatocytes for liver regeneration is a priority. Liver regeneration is a complex process regulated by growth factors (GFs), cytokines, transcription factors (TFs), hormones, oxidative stress products, metabolic networks, and microRNA. It is well-known that the function of isolated primary hepatocytes is hard to maintain; when cultured in vitro, these cells readily undergo dedifferentiation, causing them to lose hepatocyte function. For this reason, most studies focus on inducing stem cells, such as embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), hepatic progenitor cells (HPCs), and mesenchymal stem cells (MSCs), to differentiate into hepatocyte-like cells (HLCs) in vitro. In this review, we mainly focus on the nature of the liver regeneration process and discuss how to maintain and enhance in vitro hepatic function of isolated primary hepatocytes or stem cell-derived HLCs for liver regeneration. In this way, hepatocytes or HLCs may be applied for clinical use for the treatment of terminal liver diseases and may prolong the survival time of patients in the near future.

Gene expression pattern of some classes of cytochrome P-450 and glutathione S-transferase enzymes in differentiated hepatocytes-like cells from menstrual blood stem cells

Recently, valuable characteristics of menstrual blood stem cells (MenSCs) have impelled scientists to take its advantages for cell therapy of different diseases including liver disorders. In this study, we examined messenger RNA (mRNA) expression levels of phases I and II drug metabolizing enzymes including glutathione S-transferase (GST) and cytochrome P-450 (CYP) in differentiated hepatocyte-like cells from MenSCs. The isolated MenSCs were characterized and differentiated into hepatocyte-like cells using hepatocyte growth factor (HGF) and oncostatin M (OSM) in combination with other components in serum-free culture media. After primary characterization of hepatocyte markers, mRNA expression of GSTA1, GSTA2, GSTP1, CYP3A4, and CYP7A1 was assessed in differentiated cells in reference to undifferentiated cells using real-time PCR. Based on immunofluorescent staining and real-time PCR data, the differentiated MenSCs could express functional hepatocyte markers at mRNA and/or protein levels suggesting development of hepatocyte-like cells from MenSCs. Moreover, the expression levels of GSTA1, GSTA2, and CYP3A4 mRNA were upregulated in differentiated cells compared to undifferentiated cells. The expression of CYP7A1 gene was also remarkable on the last day of differentiation process. However, the expression level of GSTP1 did not exhibit statistically significant change during differentiation (P = 0.6). Based on accumulative data, MenSCs could be viewed as an accessible population of stem cells with differentiation ability into drug-metabolizing hepatocyte-like cells.

Nuclear receptor gene alteration in human induced pluripotent stem cells with hepatic differentiation propensity

AIM

Human induced pluripotent stem (hiPS) cells are an alternative cell source of regenerative medicine for liver disease. Because variations in hepatic differentiation efficacy among hiPS cells exist, it is important to select a hiPS cell line with hepatic differentiation propensity. In addition, nuclear receptors (NR) regulate essential biological processes including differentiation and development. In this study, we identified the hiPS cell line with hepatic differentiation propensity and examined expression levels of 48 NR during this process.

METHODS

We screened 28 hiPS cell lines, which are established from various tissues of healthy persons with various reprogramming methods, using a three-step differentiation method, and examined expression levels of 48 NR by quantitative real-time polymerase chain reaction during the differentiation process in the selected cells.

RESULTS

hiPS-RIKEN-2B and hiPS-RIKEN-2F cells have hepatic differentiation propensity. Differentiation propensity towards endoderm was affected by donor origin but not by reprogramming methods or cell type of origins. Expression levels of NR were closely associated with those of hepatic differentiation markers. Furthermore, expression patterns of NR were categorized as five patterns. In particular, seven NR such as chicken ovalbumin upstream promoter transcription factor 1, retinoic acid receptor α, peroxisome proliferator-activated receptor-γ, progesterone receptor, photoreceptor cell-specific nuclear receptor, tailless homolog orphan receptor and glucocorticoid receptor were identified as the genes of which expression gradually goes up with differentiation.

CONCLUSION

These findings will be useful for not only elucidating mechanisms of hepatic differentiation of hiPS cells but also cell-based therapy for liver diseases.

The WNT/β-catenin pathway is a transcriptional regulator of CYP2E1, CYP1A2, and aryl hydrocarbon receptor gene expression in primary human hepatocytes

The wingless-type MMTV integration site family (WNT)/β-catenin/adenomatous polyposis coli (CTNNB1/APC) pathway has been identified as a regulator of drug-metabolizing enzymes in the rodent liver. Conversely, little is known about the role of this pathway in drug metabolism regulation in human liver. Primary human hepatocytes (PHHs), which are the most physiologically relevant culture system to study drug metabolism in vitro, were used to investigate this issue. This study assessed the link between cytochrome P450 expression and WNT/β-catenin pathway activity in PHHs by modulating its activity with recombinant mouse Wnt3a (the canonical activator), inhibitors of glycogen synthase kinase 3β, and small-interfering RNA to invalidate CTNNB1 or its repressor APC, used separately or in combination. We found that the WNT/β-catenin pathway can be activated in PHHs, as assessed by universal β-catenin target gene expression, leucine-rich repeat containing G protein-coupled receptor 5. Moreover, WNT/β-catenin pathway activation induces the expression of CYP2E1, CYP1A2, and aryl hydrocarbon receptor, but not of CYP3A4, hepatocyte nuclear factor-4α, or pregnane X receptor (PXR) in PHHs. Specifically, we show for the first time that CYP2E1 is transcriptionally regulated by the WNT/β-catenin pathway. Moreover, CYP2E1 induction was accompanied by an increase in its metabolic activity, as indicated by the increased production of 6-OH-chlorzoxazone and by glutathione depletion after incubation with high doses of acetaminophen. In conclusion, the WNT/β-catenin pathway is functional in PHHs, and its induction in PHHs represents a powerful tool to evaluate the hepatotoxicity of drugs that are metabolized by CYP2E1.

Liver cell therapy and tissue engineering for transplantation

Liver transplantation remains the only definitive treatment for liver failure and is available to only a tiny fraction of patients with end-stage liver diseases. Major limitations for the procedure include donor organ shortage, high cost, high level of required expertise, and long-term consequences of immune suppression. Alternative cell-based liver therapies could potentially greatly expand the number of patients provided with effective treatment. Investigative research into augmenting or replacing liver function extends into three general strategies. Bioartificial livers (BALs) are extracorporeal devices that utilize cartridges of primary hepatocytes or cell lines to process patient plasma. Injection of liver cell suspensions aims to foster organ regeneration or provide a missing metabolic function arising from a genetic defect. Tissue engineering recreates the organ in vitro for subsequent implantation to augment or replace patient liver function. Translational models and clinical trials have highlighted both the immense challenges involved and some striking examples of success.

Induced pluripotent stem cells as a source of hepatocytes

During the past decade, a series of discoveries has established the potential of the so called terminally differentiated cells to transition to more primitive progenitor cells. The dramatic demonstration of the ability to reprogram differentiated somatic cells to induced pluripotent stem cells (iPSC) that can then give rise to cells of all three germ layers has opened the possibility of generating virtually any cell type in culture, from any given individual. Taking advantage of these concepts, researchers have generated iPSCs by reprogramming a wide variety of somatic cells. In addition to their practical implications, these studies have provided crucial insights into the mechanism of cell plasticity that underlies the transition from one cell type to another. Using concepts derived from research on embryological development, investigators have differentiated iPSCs to cells resembling hepatocytes in many ways. Such hepatocyte-like cells could be of enormous value in disease modeling, drug discovery and regenerative medicine. However, the currently available methods do not yield cells that fully reproduce the characteristics of adult primary hepatocytes. Thus generating hepatocytes from iPSCs is very much a work in progress. In addition to chronicling these exciting developments, this review will discuss the emergent new approaches to generating iPSCs, improving their differentiation to hepatocyte-like cells and maintaining the hepatocyte-like cells in culture for longer survival and better function.

Human induced pluripotent stem cells in hepatology: beyond the proof of concept

The discovery of the wide plasticity of most cell types means that it is now possible to produce virtually any cell type in vitro. This concept, developed because of the possibility of reprogramming somatic cells toward induced pluripotent stem cells, provides the opportunity to produce specialized cells that harbor multiple phenotypical traits, thus integrating genetic interindividual variability. The field of hepatology has exploited this concept, and hepatocyte-like cells can now be differentiated from induced pluripotent stem cells. This review discusses the choice of somatic cells to be reprogrammed by emergent new and nonintegrative strategies, as well as the application of differentiated human induced pluripotent stem cells in hepatology, including liver development, disease modeling, host-pathogen interactions, and drug metabolism and toxicity. The actual consensus is that hepatocyte-like cells generated in vitro present an immature phenotype. Currently, developed strategies used to resolve this problem, such as overexpression of transcription factors, mimicking liver neonatal and postnatal modifications, and re-creating the three-dimensional hepatocyte environment in vitro and in vivo, are also discussed.

Three-dimensional culture and cAMP signaling promote the maturation of human pluripotent stem cell-derived hepatocytes

Human pluripotent stem cells (hPSCs) represent a novel source of hepatocytes for drug metabolism studies and cell-based therapy for the treatment of liver diseases. These applications are, however, dependent on the ability to generate mature metabolically functional cells from the hPSCs. Reproducible and efficient generation of such cells has been challenging to date, owing to the fact that the regulatory pathways that control hepatocyte maturation are poorly understood. Here, we show that the combination of three-dimensional cell aggregation and cAMP signaling enhance the maturation of hPSC-derived hepatoblasts to a hepatocyte-like population that displays expression profiles and metabolic enzyme levels comparable to those of primary human hepatocytes. Importantly, we also demonstrate that generation of the hepatoblast population capable of responding to cAMP is dependent on appropriate activin/nodal signaling in the definitive endoderm at early stages of differentiation. Together, these findings provide new insights into the pathways that regulate maturation of hPSC-derived hepatocytes and in doing so provide a simple and reproducible approach for generating metabolically functional cell populations.

Mechanisms of HCV-induced liver cancer: what did we learn from in vitro and animal studies?

Hepatitis C virus (HCV) is a cause of liver diseases that range from steatohepatitis, to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). The challenge of understanding the pathogenesis of HCV-associated liver cancer is difficult as most standard animal models used in biomedical research are not permissive to HCV infection. Herein, we provide an overview of a number of creative in vivo, mostly in the mouse, and in vitro models that have been developed to advance our understanding of the molecular and cellular effects of HCV on the liver, specifically with their relevance to HCC.

Drug metabolizing enzyme and transporter protein profiles of hepatocytes derived from human embryonic and induced pluripotent stem cells

Human embryonic and induced pluripotent stem cell-derived hepatocytes (hESC-Hep and hiPSC-Hep) have the potential to provide relevant human in vitro model systems for toxicity testing and drug discovery studies. In this study, the expression and function of important drug metabolizing cytochrome P450 (CYP) enzymes and transporter proteins in hESC-Hep and hiPSC-Hep were compared to cryopreserved human primary hepatocytes (hphep) and HepG2 cells. Overall, CYP activities in hESC-Hep and hiPSC-Hep were much lower than in hphep cultured for 4 h, but CYP1A and 3A activities were comparable to levels in hphep cultured for 48h (CYP1A: 35% and 26% of 48 h hphep, respectively; CYP3A: 80% and 440% of 48 h hphep, respectively). Importantly, in hESC-Hep and hiPSC-Hep, CYP activities were stable or increasing for at least one week in culture which was in contrast to the rapid loss of CYP activities in cultured hphep between 4 and 48 h after plating. With regard to transporters, in hESC-Hep and hiPSC-Hep, pronounced NTCP activity (17% and 29% of 4 h hphep, respectively) and moderate BSEP activity (6% and 8% of 4 h hphep, respectively) were observed. Analyses of mRNA expression and immunocytochemistry supported the observed CYP and transporter activities and showed expression of additional CYPs and transporters. In conclusion, the stable expression and function of CYPs and transporters in hESC-Hep and hiPSC-Hep for at least one week opens up the possibility to reproducibly perform long term and extensive studies, e.g. chronic toxicity testing, in a stem cell-derived hepatic system.

The pharmacology of regenerative medicine

Regenerative medicine is a rapidly evolving multidisciplinary, translational research enterprise whose explicit purpose is to advance technologies for the repair and replacement of damaged cells, tissues, and organs. Scientific progress in the field has been steady and expectations for its robust clinical application continue to rise. The major thesis of this review is that the pharmacological sciences will contribute critically to the accelerated translational progress and clinical utility of regenerative medicine technologies. In 2007, we coined the phrase "regenerative pharmacology" to describe the enormous possibilities that could occur at the interface between pharmacology, regenerative medicine, and tissue engineering. The operational definition of regenerative pharmacology is "the application of pharmacological sciences to accelerate, optimize, and characterize (either in vitro or in vivo) the development, maturation, and function of bioengineered and regenerating tissues." As such, regenerative pharmacology seeks to cure disease through restoration of tissue/organ function. This strategy is distinct from standard pharmacotherapy, which is often limited to the amelioration of symptoms. Our goal here is to get pharmacologists more involved in this field of research by exposing them to the tools, opportunities, challenges, and interdisciplinary expertise that will be required to ensure awareness and galvanize involvement. To this end, we illustrate ways in which the pharmacological sciences can drive future innovations in regenerative medicine and tissue engineering and thus help to revolutionize the discovery of curative therapeutics. Hopefully, the broad foundational knowledge provided herein will spark sustained conversations among experts in diverse fields of scientific research to the benefit of all.

Strategies to produce hepatocytes and hepatocyte-like cells from pluripotent stem cells

Human embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) are a potent source for unlimited production of hepatocytes and hepatocyte-like cells that may replace primary human hepatocytes in a variety of fields including liver cell therapy, liver tissue engineering, manufacturing bioartificial liver, modeling inherited and chronic liver diseases, drug screening and toxicity testing. Human ESCs are able to spontaneously form embryoid bodies, which then spontaneously differentiate to various tissue-specific cell lineages containing a total of 10-30% albumin-producing hepatocytes and hepatocyte-like cells. Enrichment of embryoid bodies with the definitive endoderm, from which hepatocytes arise, yields increasing the final ratio of hepatocyte population up by 50-65%. Current strategies of the directed differentiation of human ESCs (and iPSCs) to hepatocytes that reproduce liver embryogenesis by sequential stimulation of culturing ESCs with tissue-specific growth factors result in achieving the differentiation rate up to 60-80%. In the future, directed differentiation of human ESCs and iPSCs to hepatocytes should be further optimized towards generating homogeneous cultures of hepatocytes in order to avoid expensive procedures of separation and isolation of hepatocytes and hepatocyte-like cells.

Use of stem cells for liver diseases-current scenario

End-stage liver disease and liver failure are major health problems worldwide leading to high mortality and morbidity and high healthcare costs. Currently, orthotropic liver transplantation is the only effective treatment available to the patients of end-stage liver disease. However, a serious shortage of liver donors, high cost, and risk of organ rejection are the major obstacles to liver transplantation. Because of the ability of stem cells for differentiation into any tissue type, they have huge potential in therapy of various end-stage or degenerative diseases and traumatic injuries. Stem cell therapy has the potential to provide a valuable adjunct and alternative to liver transplantation and has immense potential in the management of end stage liver disease and liver failure. Stem cell therapy can be mediated by either a direct contribution to the functional hepatocyte population with embryonic, induced pluripotent, or adult stem cells or by promotion of endogenous regenerative processes with bone marrow-derived stem cells. Initial translational studies have been encouraging and have suggested improved liver function in advanced chronic liver disease and enhanced liver regeneration after portal vein embolization and partial hepatic resection. Stem cells infusion in cirrhotic patients has improved liver parameters and could form a viable bridge to transplantation. The present review summarizes basic of stem cell biology relevant to clinicians and an update on recent advances on the management of liver diseases using stem cells.