Yan Min, Hu Yange, Yao Min, Bao Shisan, Fang Yong
Department of Plastic Surgery, The Ninth People's Hospital, Shanghai Jiaotong University of Medicine, Shanghai, China.
Discipline of Pathology, Bosch Institute and School of Medical Sciences, The University of Sydney, Sydney, Australia.
Wound Repair Regen. 2017 Nov;25(6):933-943. doi: 10.1111/wrr.12608. Epub 2018 Feb 16.
Skin wound healing involves complex coordinated interactions of cells, tissues, and mediators. Maintaining microvascular barrier integrity is one of the key events for endothelial homeostasis during wound healing. Vasodilation is observed after vasoconstriction, which causes blood vessels to become porous, facilitates leukocyte infiltration and aids angiogenesis at the wound-area, postinjury. Eventually, vessel integrity has to be reestablished for vascular maturation. Numerous studies have found that granulocyte macrophage colony-stimulating factor (GM-CSF) accelerates wound healing by inducing recruitment of repair cells into the injury area and releases of cytokines. However, whether GM-CSF is involving in the maintaining of microvascular barrier integrity and the underlying mechanism remain still unclear. Aim of this study was to investigate the effects of GM-CSF on modulation of microvascular permeability in wound healing and underlying mechanisms. Wound closure and microvascular leakage was investigated using a full-thickness skin wound mouse model after GM-CSF intervention. The endothelial permeability was measured by Evans blue assay in vivo and in vitro endothelium/pericyte co-culture system using a FITC-Dextran permeability assay. To identify the source of angiopoietin-1 (Ang-1), double staining is used in vivo and ELISA and qPCR are used in vitro. To determine the specific effect of Ang-1 on GM-CSF maintaining microvascular stabilization, Ang-1 siRNA was applied to inhibit Ang-1 production in vivo and in vitro. Wound closure was significantly accelerated and microvascular leakage was ameliorated after GM-CSF treatment in mouse wound sites. GM-CSF decreased endothelial permeability through tightening endothelial junctions and increased Ang-1 protein level that was derived by perictye. Furthermore, applications of siRNAAng-1 inhibited GM-CSF mediated protection of microvascular barrier integrity both in vivo and in vitro. Our data indicate that GM-CSF ameliorates microvascular barrier integrity via pericyte-derived Ang-1 during wound healing.
皮肤伤口愈合涉及细胞、组织和介质之间复杂的协同相互作用。维持微血管屏障完整性是伤口愈合过程中内皮细胞稳态的关键事件之一。受伤后，血管收缩后会出现血管舒张，这会使血管变得多孔，促进白细胞浸润并有助于伤口部位的血管生成。最终，必须重新建立血管完整性以实现血管成熟。大量研究发现，粒细胞巨噬细胞集落刺激因子（GM-CSF）通过诱导修复细胞募集到损伤区域和释放细胞因子来加速伤口愈合。然而，GM-CSF是否参与维持微血管屏障完整性及其潜在机制仍不清楚。本研究的目的是探讨GM-CSF对伤口愈合过程中微血管通透性调节的影响及其潜在机制。在GM-CSF干预后，使用全层皮肤伤口小鼠模型研究伤口闭合和微血管渗漏情况。通过伊文思蓝测定法在体内以及在体外内皮细胞/周细胞共培养系统中使用异硫氰酸荧光素-葡聚糖通透性测定法测量内皮通透性。为了确定血管生成素-1（Ang-1）的来源，在体内使用双重染色，在体外使用酶联免疫吸附测定法（ELISA）和定量聚合酶链反应（qPCR）。为了确定Ang-1对GM-CSF维持微血管稳定性的具体作用，在体内和体外应用Ang-1小干扰RNA（siRNA）抑制Ang-1的产生。GM-CSF处理后，小鼠伤口部位的伤口闭合明显加速，微血管渗漏得到改善。GM-CSF通过收紧内皮连接降低内皮通透性，并增加周细胞衍生的Ang-1蛋白水平。此外，应用siRNA-Ang-1在体内和体外均抑制了GM-CSF介导对微血管屏障完整性的保护作用。我们的数据表明，在伤口愈合过程中，GM-CSF通过周细胞衍生的Ang-1改善微血管屏障完整性。
