Identification of endothelial progenitor cells derived from cultured fibroblasts of the rat dermis

血管发生是指血管形成间充质细胞向内皮祖细胞转化的过程。尽管近年来的研究者们坚持认为骨髓来源的EPCs通过外周血管主要参与成人组织创伤愈合过程中的血管生成，但我们已经报道了来源于组织成纤维细胞的多能间充质细胞转化为EPCs并参与血管生长的加速。本研究对体外培养的大鼠真皮成纤维细胞来源的EPCs进行了超微结构和免疫细胞化学分析。深度麻醉的成年Wistar大鼠背部皮肤活检，然后在胶原包被的细胞培养皿上培养成纤维细胞。细胞培养于37℃、含5%CO_2和95%空气混合气体的培养箱中，培养液中加入胎牛血清、10 ng/ml碱性成纤维细胞 ...更多信息 生长因子和10 ng/ml血管内皮生长因子。这些培养的细胞制备的光镜免疫细胞化学和电子显微镜，分别。这些细胞在第一时间达到单层融合，没有显示出血管性血友病因子的免疫反应性。几天后，一些培养的细胞具有丰富的胞质突起，偶尔与相邻的细胞接触，形成固体细胞索。由于这些细胞显示血管性血友病因子的免疫反应性，并拥有许多韦伯-帕拉德（WP）体，我们将其定义为EPCs的表型。内皮素（ET）-1、大内皮素-1和内皮素转换酶（ECE）-1免疫反应阳性。由于ET-1和ECE-1储存在内皮细胞的WP体中被广泛接受，我们现在认为以具有WP体为特征的成纤维细胞来源的EPCs可能已经转化为内皮细胞并具有合成ET-1的能力。少

Vasculogenesis is defined as a neovascularization process by transformation of vasoformative mesenchymal cells to endothelial progenitor cells (EPCs). Although recent researchers insisted that bone marrow-derived EPCs via peripheral blood vessels are mainly involved in vasculogenesis during wound healing process of adult tissues, we have reported that multipotent mesenchymal cells derived from tissue fibroblasts located in several adult tissues transform to EPCs and participate in the acceleration of the vascular growth. This study deals with ultrastructural and immunocytochemical analyses on EPCs derived from cultured fibroblasts of the rat dermis. Deeply anesthetized adult Wistar rats received skin-biopsy in their back skin, and then fibroblasts were cultured on collagen-coated cell dishes. These cells were maintained in a humidified incubator containing a gas mixure of 5% CO_2 in 95% air at 37℃, and fed a cultured medium supplemented with fetal bovine serum, 10ng/ml basic fibroblast … More growth factor and 10ng/ml Vascular endothelial groeth factor. These cultured cells were prepared for light microscopic immunocytochemistry and electron microscopy, respectively. These cells, which reached monolayer confluence in the first time, showed no immunoreactivities for von Willebrand factor. After several days, some cultured cells possessed an abundance of cytoplasmic projections and were occasionally in contact with the neighboring ones forming solid cell cords. Since these cells showed immunoreactivities for von Willebrand factor and possessed many Weibel-Palade (WP) bodies, we defined them as phenotypes of EPCs. In addition, immunoreactivities for endothelin (ET)-1, big ET-1 and ET converting enzayme (ECE)-1 were seen in such EPCs. Since it is widely accepted that ET-1 and ECE-1 are stored in WP bodies of endothelial cells, we consider now that fibroblast-derived EPCs which are characterized by possessing WP bodies may be already transformed into endothelial cells and have ability to synthesize ET-1. Less