Specialized tip/stalk-like and phalanx-like endothelial cells from embryonic stem cells

Stem Cells Dev. 2013 May 1;22(9):1398-407. doi: 10.1089/scd.2012.0376. Epub 2013 Feb 12.

Abstract

Endothelial cells (EC) generated in vitro from stem cells are desirable for their potential in a variety of in vitro models and cell-based therapeutic approaches; however, EC can take on a number of functionally and phenotypically distinct specializations. Here, we show the generation of functionally distinct EC subpopulations, including (1) the pro-angiogenic migrating tip-like and proliferative stalk-like EC, and (2) the less migratory cobblestone-shaped phalanx-like EC. Both embryonic stem cell (ESC)-derived EC subpopulations are generated from outgrowths of Flk-1+ vascular progenitor cells with high levels of vascular endothelial growth factor treatment, while the phalanx-like ESC-derived EC (ESC-EC) are subsequently isolated by selecting for cobblestone shape. Compared with the ESC-derived angiogenic endothelial cells (named ESC-AEC) that contain only 14% Flt-1+ and 25% Tie-1+ cells, the selected phalanx-like ESC-EC express higher numbers of cells expressing the phalanx markers Flt-1+ and Tie-1+, 89% and 90%, respectively. The ESC-AEC also contain 35% CXCR4+ tip cells, higher expression levels of stalk marker Notch-1, and lower expression levels of Tie-2 compared with the phalanx-type ESC-EC that do not contain discernible numbers of CXCR4+ tip cells. Perhaps most notably, the ESC-AEC display increased cell migration, proliferation, and 3 times more vessel-like structures after 48 h on Matrigel compared with the phalanx-like ESC-EC. This work analyzes, for the first time, the presence of distinct EC subtypes (tip/stalk, and phalanx) generated in vitro from ESC, and shows that phalanx-like EC can be purified and maintained in culture separate from the tip/stalk-like containing EC.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Biomarkers / metabolism
  • Cell Movement
  • Cell Proliferation
  • Cell Shape
  • Cells, Cultured
  • Embryonic Stem Cells / physiology*
  • Endothelial Cells / physiology*
  • Endothelium, Vascular / cytology
  • Mice
  • Neovascularization, Physiologic
  • Phenotype
  • Receptor, TIE-2 / metabolism
  • Receptors, CXCR4 / metabolism

Substances

  • Biomarkers
  • CXCR4 protein, mouse
  • Receptors, CXCR4
  • Receptor, TIE-2
  • Tek protein, mouse