SIRPA, VCAM1 and CD34 identify discrete lineages during early human cardiovascular development

• Main Authors: Rhys J.P. Skelton, Magdaline Costa, David J. Anderson, Freya Bruveris, Ben W. Finnin, Katerina Koutsis, Deevina Arasaratnam, Anthony J. White, Arash Rafii, Elizabeth S. Ng, Andrew G. Elefanty, Edouard G. Stanley, Colin W. Pouton, John M. Haynes, Reza Ardehali, Richard P. Davis, Christine L. Mummery, David A. Elliott
• Format: Article
• Language: English
• Published: Elsevier 2014-07-01
• Series: Stem Cell Research
• Online Access: http://www.sciencedirect.com/science/article/pii/S187350611400052X

The study of human cardiogenesis would benefit from a detailed cell lineage fate map akin to that established for the haematopoietic lineages. Here we sought to define cell lineage relationships based on the expression of NKX2-5 and the cell surface markers VCAM1, SIRPA and CD34 during human cardiovascular development. Expression of NKX2-5GFP was used to identify cardiac progenitors and cardiomyocytes generated during the differentiation of NKX2-5GFP/w human embryonic stem cells (hESCs). Cardiovascular cell lineages sub-fractionated on the basis of SIRPA, VCAM1 and CD34 expression were assayed for differentiation potential and gene expression. The NKX2-5posCD34pos population gave rise to endothelial cells that rapidly lost NKX2-5 expression in culture. Conversely, NKX2-5 expression was maintained in myocardial committed cells, which progressed from being NKX2-5posSIRPApos to NKX2-5posSIRPAposVCAM1pos. Up-regulation of VCAM1 was accompanied by the expression of myofilament markers and reduced clonal capacity, implying a restriction of cell fate potential. Combinatorial expression of NKX2-5, SIRPA, VCAM1 and CD34 can be used to define discrete stages of cardiovascular cell lineage differentiation. These markers identify specific stages of cardiomyocyte and endothelial lineage commitment and, thus provide a scaffold for establishing a fate map of early human cardiogenesis.