AC133+ / CD34+ cells isolated from
human bone marrow can be stimulated with the pro-angiogenic factors VEGF, bFGF, and
heparin, resulting in the generation of a
population of cells that is adherent and possesses many of the same properties as mature endothelial
cell types, HMVECs and HUVECs. The newly-formed, endothelial-like cells are referred as adherent endothelial precursor cells (aEPCs); these cells appear to be intermediates between haematopoietic stem cells (HSCs) and mature endothelial cells. Direct comparison of aEPCs with HMVECs and HUVECs in several
in vitro functional assays, such as
tube formation, migration, invasion, and expression of cells surface markers, reveals differences and similarities. In a
Matrigel™ matrix
angiogenesis assay the aEPCs form vessels
in vivo and interact with human
ovarian cancer cells. Mouse
cell lines that are useful models for tumor endothelial cells are identified by determining mRNA and
protein expression levels of murine homologs of tumor endothelial markers. Mouse
cell lines selected as models for tumor endothelial cells can be used to evaluate pro-angiogenic and anti-angiogenic factors.