Characterization of vascular endothelial progenitor cells from chicken bone marrow

We found that the majority of chicken EPCs were spindle shaped. The growth-curves of chicken EPCs at passages (P) 1, -5 and -9 were typically “S”-shaped. The viability of chicken EPCs, before and after cryopreservation was 92.2% and 81.1%, respectively. Thus, cryopreservation had no obvious effects on the viability of chicken EPCs. Dil-ac-LDL and FITC-UAE-1 uptake assays and immunofluorescent detection of the cell surface markers CD34, CD133, VEGFR-2 confirmed that the cells obtained in vitro were EPCs. Observation of endothelial-specific Weibel-Palade bodies using transmission electron microscopy further confirmed that the cells were of endothelial lineage. In addition, chicken EPCs differentiated into endothelial cells and smooth muscle cells upon induction with VEGF and PDGF-BB, respectively, suggesting that the chicken EPCs retained multipotency in vitro.These results suggest that chicken EPCs not only have strong self-renewal capacity, but also the potential to differentiate into endothelial and smooth muscle cells. This research provides theoretical basis and experimental evidence for potential therapeutic application of endothelial progenitor cells in the treatment of atherosclerosis, vascular injury and diabetic complications.Endothelial progenitor cells (EPCs) are precursors of vascular endothelial cells. Progenitor cells [1]. EPCs originate from bone marrow with similar angioblast and umbilical vein endothelial cells, which together belong to a subgroup of hematopoietic stem cells [2].There are two types of EPCs that can be detected in vitro, early and late EPCs. While early EPCs display a linear growth structure termed spindle-shaped, late EPCs form cobblestone-like, oval shaped strutures [3]. EPCs not only take part in vascularization during embryonic development, but also participate in postnatal vascularization and reparative processes post-trauma [4]. Therefore, EPCs hold extensive prospects for vascular tissue engineering and possible clinical applic