ABSTRACT
Renewal ..................................................................................7 1.3 Differentiation of Human Embryonic Stem Cells ............................................8
1.3.1 In Vivo Differentiation: Teratoma Formation .......................................8 1.3.2 In Vitro Three-Dimensional Differentiation.........................................9 1.3.3 Two-Dimensional Differentiation of Human ES Cells ....................... 10 1.3.4 Growth Factor-Induced Differentiation ............................................. 10 1.3.5 Small Molecule-Induced Differentiation ........................................... 11 1.3.6 In Vitro Differentiation into the Three Germ Layer Lineages ........... 11
1.3.6.1 Differentiation into Mesoderm: Endothelial Cells .............. 11 1.3.6.2 Differentiation into Endoderm: Pancreatic Cell
Differentiation ...................................................................... 13 1.3.6.3 Differentiation into Ectoderm: Neural Differentiation ........ 14
1.4 Therapeutic Potential of Human Embryonic Stem Cells ............................... 15 1.4.1 Vascular Applications of Human Embryonic Stem Cells................... 15 1.4.2 Challenges in Using Human ES Cells for Clinical Applications ....... 17
1.5 Conclusions ..................................................................................................... 18 Acknowledgment ..................................................................................................... 18 References ................................................................................................................ 18
Stem cells are characterized by their abilities to inde—nitely self-renew and to differentiate into a diverse range of specialized cell types. The last decade has witnessed signi—cant progress and achievements in the —eld of stem cell applications, due to landmarks, including the isolation of murine embryonic stem (ES) cells in 1981,1,2 which paved the way for basic research of the subsequent landmark, the isolation of human ES cells, in 1998.3 Human ES cells bear the capacity to massively generate virtually any cell type and tissue of the human body, rendering them an ideal cell supply for tissue engineering therapies, which carry the potential of curing a variety of human diseases. However, a thorough understanding of stem cell origin, characteristics, and the molecular basis underlying their differentiation potential are prerequisites to their effective application in regenerative medicine. This chapter will focus on the characterization, derivation, and multilineage differentiative potential of human ES cells and will also touch upon their vascular lineage pathway and its potential implications in neovascularization applications.
