  There are a number of different stem cell sources that have the potential to
be used as therapeutics in vascular degenerative diseases. On the one hand,
there are so called endothelial progenitor cells (EPCs), which are typically
derived from adult blood. They carry the marker CD34, but the true nature and
definition of EPCs is still controversial. On the other hand, there are
embryonic precursors of endothelial cells (PECs), which also express CD34, and
can be differentiated from embryonic stem cells (ESCs) or induced pluripotent
stem cells (iPSCs) in vitro. In this study, it was aimed to compare these two
different CD34 positive cell populations by full genome transcriptional
profiling (RNAseq). To this end, we firstly optimised a PEC differentiation
protocol and found that vascular endothelial growth factor (VEGF) is critical
for the transition of cells from mesodermal precursors to PECs. Additionally,
principal component analysis (PCA) of RNAseq data showed that blood-derived
EPCs clustered far from iPS-derived PECs which illustrates these populations
are fundamentally different. This data will be useful to better define these
cell populations and facilitating the translation of regenerative approaches in
this field as well as providing potentially novel diagnostic tools.
