Nakul-Aquaronne Danièle, Bayle Jacques, Frelin Christian
Institut de Pharmacologie Moléculaire et Cellulaire du CNRS, 660 route des Lucioles, 06560 Valbonne, France.
Cardiovasc Res. 2003 Mar;57(3):816-23. doi: 10.1016/s0008-6363(02)00776-9.
A subset of adult peripheral blood leukocytes functions as endothelial progenitor cells that incorporate into the vasculature in animal models of neovascularization. The basic mechanisms by which differentiation proceeds are still unclear. This study analyses the in vitro differentiation of cytokine mobilized, human CD34(+) cells.
Granulocyte-monocyte colony stimulating factor mobilized human CD34(+) cells were isolated and grown in culture in the presence of vascular endothelial growth factor (50 ng/ml) and basic fibroblast growth factor (10 ng/ml). Their differentiation was followed using cytological and immunohistochemical techniques. Fibronectin-coated culture dishes or three-dimensional cultures were used.
CD34(+) cells grown on fibronectin-coated dishes differentiated along the granulocytic and monocytic/macrophage lineages with no evidence for an endothelial cell differentiation. CD14(+) macrophages appeared in long-term culture and then acquired endothelial cell markers such as VE-cadherin, the endothelial form of NO synthase and the von Willebrand factor. Yet they were unable to form tubular structures in Matrigel. Only typical macrophages were observed in Matrigel.
Angiogenic stimulation of CD34(+) precursor cells leads to cells that expressed mixed macrophage and endothelial cell properties. They could represent an intermediate phenotype in the pathway that leads to mature endothelial cells.
在新生血管形成的动物模型中，成年外周血白细胞的一个亚群可作为内皮祖细胞整合到脉管系统中。分化过程的基本机制仍不清楚。本研究分析了细胞因子动员的人CD34(+)细胞的体外分化情况。
分离粒细胞-单核细胞集落刺激因子动员的人CD34(+)细胞，并在血管内皮生长因子（50 ng/ml）和碱性成纤维细胞生长因子（10 ng/ml）存在的情况下进行培养。使用细胞学和免疫组织化学技术追踪其分化情况。使用纤连蛋白包被的培养皿或三维培养。
在纤连蛋白包被的培养皿上生长的CD34(+)细胞沿粒细胞和单核细胞/巨噬细胞谱系分化，没有内皮细胞分化的证据。CD14(+)巨噬细胞出现在长期培养中，然后获得内皮细胞标志物，如VE-钙黏蛋白、内皮型一氧化氮合酶和血管性血友病因子。然而，它们无法在基质胶中形成管状结构。在基质胶中仅观察到典型的巨噬细胞。
对CD34(+)前体细胞的血管生成刺激导致表达混合巨噬细胞和内皮细胞特性的细胞产生。它们可能代表通向成熟内皮细胞途径中的一种中间表型。
