In Vitro Differentiation of Embryonic and Adult Stem Cells into Hepatocytes: State of the Art

Abstract

Stem cells are a unique source of self-renewing cells within the human body. Before the end of the last millennium, adult stem cells, in contrast to their embryonic counterparts, were considered to be lineage-restricted cells or incapable of crossing lineage boundaries. However, the unique breakthrough of muscle and liver regeneration by adult bone marrow stem cells at the end of the 1990s ended this long-standing paradigm. Since then, the number of articles reporting the existence of multipotent stem cells in skin, neuronal tissue, adipose tissue, and bone marrow has escalated, giving rise, both in vivo and in vitro, to cell types other than their tissue of origin. The phenomenon of fate reprogrammation and phenotypic diversification remains, though, an enigmatic and rare process. Understanding how to control both proliferation and differentiation of stem cells and their progeny is a challenge in many fields, going from preclinical drug discovery and development to clinical therapy. In this review, we focus on current strategies to differentiate embryonic, mesenchymal(-like), and liver stem/progenitor cells into hepatocytes in vitro. Special attention is paid to intracellular and extracellular signaling, genetic modification, and cell-cell and cell-matrix interactions. In addition, some recommendations are proposed to standardize, optimize, and enrich the in vitro production of hepatocyte-like cells out of stem/progenitor cells.

Sustained Delivery Growth Factors with Polyethyleneimine‐Modified Nanoparticles Promote Embryonic Stem Cells Differentiation and Liver Regeneration

“…Activin A has been reported to induce definitive endoderm differentiation of ESCs;10, 32 DE cells constitute the embryonic germ layer that produces hepatic cells;33 aFGF and HGF are essential for liver development, with aFGF efficiently initiating hepatic differentiation of ESCs from the definitive endoderm and HGF promoting hepatic growth 34, 35. The novel growth factors delivery system was prepared by mixing Activin A, aFGF, and HGF with positively charged PEI‐MSNs.…”

Dental Kök Hücreler Ve Süt Di̇şleri̇ni̇n Kök Hücre Çalişmalarindaki̇ Önemi̇

“…Anne karnındaki gelişimin 5'inci günlerinde oluşan hücre topluluğuna blastosist adı verilir ve bu hücre kümesinin iç kısmındaki hücrelerden elde edilen hücrelerin her birine de embriyonel kök hücre denilmektedir ve bu hücreler de pluripotent özellik taşımaktadır. 10 Embriyonel kök hücreler in vitro olarak bütün somatik hücrelere dönüşebilme yeteneği sahiptirler. Bu hücreler tek başlarına insan oluşturamamakta ama insan vücudunda 200'den fazla sayıda değişik hücre türlerine dönüşebilmektedir.…”

Dental Kök Hücre Kaynaklari Ve Kemi̇k Doku Rejenerasyonunda Kullanilma Potansi̇yelleri̇

“…23,24 Embriyonik kök hücrelerin farklılaşma yeteneğinin fazla olması, bu hücreleri daha değerli kılmaktadır. 18 Ancak embriyonik kök hücrelerin elde edilmesindeki etik ve yasal tartışmalar ve tümör oluşma riski vardır. 25 Bu nedenle araştırmacılar erişkin kök hücreler üzerine odaklanmıştır.…”