Fujiyama Soichiro, Amano Katsuya, Uehira Kazutaka, Yoshida Masayuki, Nishiwaki Yasunobu, Nozawa Yoshihisa, Jin Denan, Takai Shinji, Miyazaki Mizuo, Egashira Kensuke, Imada Takayuki, Iwasaka Toshiji, Matsubara Hiroaki
Department of Medicine II, Kansai Medical University, Japan.
Circ Res. 2003 Nov 14;93(10):980-9. doi: 10.1161/01.RES.0000099245.08637.CE. Epub 2003 Oct 2.
Peripheral blood (PB)-derived CD14+ monocytes were shown to transdifferentiate into endothelial cell (EC) lineage cells and contribute to neovascularization. We investigated whether bone marrow (BM)- or PB-derived CD34-/CD14+ cells are involved in reendothelialization after carotid balloon injury. Although neither hematopoietic nor mesenchymal stem cells were included in human BM-derived CD34-/CD14+ monocyte lineage cells (BM-MLCs), they expressed EC-specific markers (Tie2, CD31, VE-cadherin, and endoglin) to an extent identical to mature ECs. When BM-MLCs were cultured with vascular endothelial growth factors, hematopoietic markers were drastically decreased and new EC-specific markers (Flk and CD34) were induced. BM-MLCs were intra-arterially transplanted into balloon-injured arteries of athymic nude rats. When BM-MLCs were activated by monocyte chemoattractant protein-1 (MCP-1) in vivo or in vitro, they adhered onto injured endothelium, differentiated into EC-like cells by losing hematopoietic markers, and inhibited neointimal hyperplasia. Ability to prevent neointimal hyperplasia was more efficient than that of BM-derived CD34+ cells. MCP-dependent adhesion was not observed in PB-derived CD34-/CD14+ monocytes. Regenerated endothelium exhibited a cobblestone appearance, blocked extravasation of dye, and induced NO-dependent vasorelaxation. Basal adhesive activities on HUVECs under laminar flow and beta1-integrin expression (basal and active forms) were significantly increased in BM-MLCs compared with PB-derived monocytes. MCP-1 markedly enhanced adhesive activity of BM-MLCs (2.8-fold) on HUVECs by activating beta1-integrin conformation. Thus, BM-MLCs can function as EC progenitors that are more potent than CD34+ cells and acquire the ability to adhere on injured endothelium in a MCP-1-dependent manner, leading to reendothelialization associated with inhibition of intimal hyperplasia. This will open a novel window to MCP-1-mediated biological actions and vascular regeneration strategies by cell therapy.
外周血（PB）来源的CD14⁺单核细胞可转分化为内皮细胞（EC）谱系细胞并促进新血管形成。我们研究了骨髓（BM）或PB来源的CD34⁻/CD14⁺细胞是否参与颈动脉球囊损伤后的再内皮化过程。虽然人BM来源的CD34⁻/CD14⁺单核细胞谱系细胞（BM-MLCs）中既不包含造血干细胞也不包含间充质干细胞，但它们表达EC特异性标志物（Tie2、CD31、血管内皮钙黏蛋白和内皮糖蛋白）的程度与成熟ECs相同。当BM-MLCs与血管内皮生长因子一起培养时，造血标志物急剧减少，新的EC特异性标志物（Flk和CD34）被诱导产生。将BM-MLCs经动脉内移植到无胸腺裸鼠的球囊损伤动脉中。当BM-MLCs在体内或体外被单核细胞趋化蛋白-1（MCP-1）激活时，它们黏附到受损内皮上，通过丢失造血标志物分化为类EC细胞，并抑制内膜增生。预防内膜增生的能力比BM来源的CD34⁺细胞更有效。在PB来源的CD34⁻/CD14⁺单核细胞中未观察到MCP依赖性黏附。再生内皮呈现鹅卵石样外观，阻止染料外渗，并诱导一氧化氮依赖性血管舒张。与PB来源的单核细胞相比，BM-MLCs在层流条件下对人脐静脉内皮细胞（HUVECs）的基础黏附活性和β1整合素表达（基础形式和活性形式）显著增加。MCP-1通过激活β1整合素构象显著增强BM-MLCs对HUVECs的黏附活性（2.8倍）。因此，BM-MLCs可作为比CD34⁺细胞更有效的EC祖细胞，并以MCP-1依赖性方式获得黏附到受损内皮的能力，导致与内膜增生抑制相关的再内皮化。这将为MCP-1介导的生物学作用和细胞治疗的血管再生策略打开一个新窗口。
