Table 2.

Comparison of available stem cell sources for hepatic differentiation and subsequent use in in vitro liver cell culture models with respect to their properties and potential application fields

Cell type	Characteristics		Application examples
	Advantages	Disadvantages
Adult stem cells	• Option for patient-specific derivation	• Limited proliferation capacity	• Characterization of differentiation/maturation processes for potential in vitro or clinical use92,94,95,97–99
Liver progenitor cells	• Committed to the hepatic lineage, facilitating differentiation	• Scarce tissue availability • Low frequency in tissue
Mesenchymal stem cells	• Good availability (e.g. from bone marrow, placenta, umbilical cord)	• Incomplete hepatic differentiation with current protocols
Pluripotent stem cells	• Unlimited growth	• Fetal phenotype of differentiated cells with current protocols • Lack of standardized methods for cell differentiation and characterization	• Use in drug metabolism and toxicity studies119,146,147 • Research on applications in regenerative medicine122
hESC	• Differentiation not affected by epigenetic memory	• Ethical considerations restrict research on hESC in dependence of national regulations
hiPSC	• Good availability • No ethical restrictions • Option for derivation from different individuals and patient groups	• Epigenetic memory may impair hepatic differentiation	• Analysis of genetic polymorphisms • Establishment of disease models149–153 • Drug testing with patient-specific cell lines for personalized medicine155