School of Mechanical and Electronic Engineering, Soochow University, 178 Ganjiang East Road, Suzhou 215006, China; College of Textile and Clothing Engineering, Soochow University, 178 Ganjiang East Road, Suzhou 215006, China.
Microvasc Res. 2013 Nov;90:1-11. doi: 10.1016/j.mvr.2013.06.010. Epub 2013 Jul 11.
Since bone marrow-derived endothelial progenitor cells (EPCs) have been detected in adult peripheral blood, the mode of vasculogenesis in the adult tissue has caught attention in field of vascularization research. To confirm the role of EPCs in construction of new vascular loop, we took the biomaterial scaffold implanted into adult rat as an experimental model to observe and examine the actions of the EPCs in neovascularization of the material by immunohistochemistry and transmission electron microscopy. Additionally, by establishing a chemotactic migration model for vascular endothelial cells (ECs) and EPCs, the migrations of ECs and EPCs were explored in simulations. The results of 20,000 simulations showed that the number of the vascular loops assisted by the EPCs was 2-5 times that of the vascular sprouts being naturally joined. Based on the results of experiments and simulations, we conclude that the EPCs are able to assist the angiogenic sprouts in joining under the condition of plenty of the EPCs being mobilized, which aggregate at sites close to sprout tips, forming a cell cord and differentiating to ECs in situ, and become vessel segments between neighboring sprouts. This suggests that there is a difference between the adult and embryo in the manner of vasculogenesis and that a small number of EPCs can play an important role to make the new blood vessels achieve rapid functionalization.
由于骨髓来源的内皮祖细胞 (EPCs) 已在成人外周血中被检测到，因此成人组织中的血管发生模式在血管生成研究领域引起了关注。为了确认 EPCs 在新血管环构建中的作用，我们采用将生物材料支架植入成年大鼠的实验模型，通过免疫组织化学和透射电子显微镜观察和检查 EPCs 在材料新生血管化中的作用。此外，通过建立血管内皮细胞 (ECs) 和 EPCs 的趋化迁移模型，模拟探索 ECs 和 EPCs 的迁移。20,000 次模拟的结果表明，EPCs 辅助的血管环数量是自然连接的血管芽的 2-5 倍。基于实验和模拟的结果，我们得出结论，在大量动员 EPCs 的情况下，EPCs 能够协助血管生成芽的连接，它们聚集在芽尖附近的部位，形成细胞索，并在原位分化为 ECs，成为相邻芽之间的血管段。这表明成人和胚胎在血管发生方式上存在差异，少量的 EPCs 可以发挥重要作用，使新血管迅速实现功能化。
