Zhao Zhiqiang, Qin Lu, Reid Brian, Pu Jin, Hara Takahiko, Zhao Min
School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK.
Stem Cell Res. 2012 Jan;8(1):38-48. doi: 10.1016/j.scr.2011.08.001. Epub 2011 Aug 16.
Naturally-occurring, endogenous electric fields (EFs) have been detected at skin wounds, damaged tissue sites and vasculature. Applied EFs guide migration of many types of cells, including endothelial cells to migrate directionally. Homing of endothelial progenitor cells (EPCs) to an injury site is important for repair of vasculature and also for angiogenesis. However, it has not been reported whether EPCs respond to applied EFs. Aiming to explore the possibility to use electric stimulation to regulate the progenitor cells and angiogenesis, we tested the effects of direct-current (DC) EFs on EPCs. We first used immunofluorescence to confirm the expression of endothelial progenitor markers in three lines of EPCs. We then cultured the progenitor cells in EFs. Using time-lapse video microscopy, we demonstrated that an applied DC EF directs migration of the EPCs toward the cathode. The progenitor cells also align and elongate in an EF. Inhibition of vascular endothelial growth factor (VEGF) receptor signaling completely abolished the EF-induced directional migration of the progenitor cells. We conclude that EFs are an effective signal that guides EPC migration through VEGF receptor signaling in vitro. Applied EFs may be used to control behaviors of EPCs in tissue engineering, in homing of EPCs to wounds and to an injury site in the vasculature.
在皮肤伤口、受损组织部位和脉管系统中已检测到天然存在的内源性电场（EFs）。施加的电场可引导多种类型细胞的迁移，包括内皮细胞定向迁移。内皮祖细胞（EPCs）归巢至损伤部位对于脉管系统修复以及血管生成均很重要。然而，尚未有关于EPCs是否对施加的电场作出反应的报道。为了探索利用电刺激调节祖细胞和血管生成的可能性，我们测试了直流电（DC）电场对EPCs的影响。我们首先使用免疫荧光法确认了三株EPCs中内皮祖细胞标志物的表达。然后我们在电场中培养祖细胞。使用延时视频显微镜，我们证明施加的DC电场可引导EPCs向阴极迁移。祖细胞在电场中也会排列并伸长。血管内皮生长因子（VEGF）受体信号传导的抑制完全消除了电场诱导的祖细胞定向迁移。我们得出结论，电场是一种有效的信号，可在体外通过VEGF受体信号传导引导EPC迁移。施加的电场可用于控制组织工程中EPCs的行为、EPCs向伤口以及脉管系统损伤部位的归巢。
