静脉注射携带缺氧诱导因子的内皮祖细胞对裸鼠缺血下肢血管新生的作用

Adenoviral Transfer of Hypoxia Inducible Factor In Endothelial Progenitor Cells for Vascular Regeneration and Possible Mechanism

目的探讨静脉注射携带缺氧诱导因子1α的内皮祖细胞对裸鼠缺血下肢血管新生的作用及机制。方法在体外将腺病毒介导人缺氧诱导因子1α基因入人外周血内皮祖细胞,观察转染后的内皮祖细胞在裸鼠缺血下肢局部的促血管新生作用,并探讨其可能的作用机制。结果转染腺病毒—缺氧诱导因子1α后的内皮祖细胞在细胞内有效并持续表达;移植异种腺病毒—缺氧诱导因子1α内皮祖细胞至Balb/c鼠缺血下肢后可见外源性内皮祖细胞定向作用于缺血部位;移植腺病毒—缺氧诱导因子1α内皮祖细胞组较对照组明显促进体内毛细血管数目增加(P<0.05);mRNA检测提示过表达缺氧诱导因子1α基因可上调其下游的基质细胞衍生因子、CXCR4因子(P<0.05),增加内皮祖细胞招募,同时促血管内皮生长因子水平上调(P<0.05)。结论在体内,转染腺病毒—缺氧诱导因子1α的内皮祖细胞可促进缺血下肢的局部血管新生,这种内皮祖细胞数量的增加可能与基质细胞衍生因子、CXCR4的招募及血管内皮生长因子的分泌增加有关。

Aim To detemaine tile consequences of hypoxia inducible factor-la （HIF-1α）-modified endothelial progenitor cells （ EPC ） on neovascularization in vivo and discussed the possible mechanisms of homing. Methods Adenovirus mediated human HIF-1α （Ad-HIF-1α） were transduced in human EPC in vitro. To detemaine if such transduced EPC may facilitate therapeutic neovascularization, heterologotts EPC transduced with adenovirus encoding HIF-1α were administered to Balb/c nude mice with hindlimb ischemia. Exogenous EPC homing was observed and the possible mechanism of EPC homing was explored. Results Adenovirus mediated green fluorescence protein （GFP） was consistently expressed in EPC. A significantly higher capillary/myocyte ratio in mice transplanted with Ad-HIF-1α-EPC than in those receiving Ad-GFP-EPC at each time point was found. HIF-1α mRNA and protein expression in the ischemia zone was enhanced （ P 〈 0.05 ）. Stromal derived factor （SDF） and CXCR4 upregulation were accompanied by paralleled vascular endothelial growth factor （VEGF） upregtdation （ P 〈 0.05）. Conclusions In vivo, gene-modified EPC facilitate the strategy, of cell transplantation to augment naturally impaired neevasculafization in an animal model of experimentally induced limb ischemia. The recruitment of EPC may be due to the inducement of SDF, CXCR4 and the VEGF induction may contribute to the EPC proliferation.