P47 Hypercapnia impairs the ability of mesenchymal stem cells to promote distal lung epithelial wound repair in ards
P47 Hypercapnia impairs the ability of mesenchymal stem cells to promote distal lung epithelial wound repair in ards
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P47 高碳酸血症损害间充质干细胞促进ARDS远端肺上皮伤口修复的能力
DOI：
10.1136/thoraxjnl-2017-210983.189
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Fergie N
中科院分区：
文献类型：
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作者：
Fergie N
研究背景肺泡上皮细胞死亡和基底膜剥脱是急性呼吸窘迫综合征（ARDS）的重要病理生理特征。成功恢复需要基底膜上皮再生。虽然迄今为止还没有针对ARDS的药物治疗，但间充质干细胞（MSC）显示出有希望的治疗潜力，并正在早期临床试验中进行测试。ARDS患者的异质性是进一步发展基于MSC的治疗的障碍。虽然20%的ARDS患者由于肺保护性通气而发生高碳酸血症（高CO2），但在这种情况下从未研究过MSC的疗效。我们以前已经发现，功能性线粒体转移到周围细胞是MSC治疗效果的重要机制。因此，本研究的目的是研究MSC对ARDS体外模型中正常碳酸血症和高碳酸血症下远端肺上皮修复的影响，并评估线粒体转移在介导MSC效应中的作用。在正常碳酸血症（5%CO2）或高碳酸血症（15%CO2）中与MSC共培养。在24小时测量伤口闭合百分比。通过Ki 67染色评估SAEC增殖。使用MitoTracker绿色染料通过流式细胞术评估从MSC到SAEC的线粒体转移。使用JC-1通过流式细胞术分析MSC线粒体膜电位。ATP的产生测定发光assay.ResultsEpithelial伤口闭合受损高碳酸血症。MSC通过增强的迁移促进了正常碳酸血症中炎症环境中的上皮伤口闭合。这种修复能力在高碳酸血症中丧失。在正常碳酸血症和高碳酸血症中，观察到从MSC到SAEC的线粒体转移达到相似的程度。然而，高碳酸血症衰减的线粒体膜电位和ATP的生产在MSCs.ConclusionWhile他们促进上皮伤口修复的炎症环境中的normocapnia，MSC失去这种能力在高碳酸血症。这表明，在这种环境中，它们的治疗功效可能会丧失。高碳酸血症对MSC线粒体功能的抑制作用可能至少部分导致这种作用。
BackgroundAlveolar epithelial cell death and denudation of the basement membrane are hallmarks in the pathophysiology of Acute Respiratory Distress Syndrome (ARDS). Successful recovery requires basement membrane re-epithelialisation. While no pharmacological therapy exists for ARDS to date, Mesenchymal Stem Cells (MSCs) demonstrate promising therapeutic potential and are being tested in early-phase clinical trials. Heterogeneity of patients with ARDS is an obstacle for further development of an MSC-based therapy. While 20% of patients with ARDS develop hypercapnia (high CO2) as a result of lung protective ventilation, the efficacy of MSCs has never been studied in this setting. We have previously found that transfer of functional mitochondria to surrounding cells is an important mechanism of the MSC therapeutic effect. Theaimsof this study therefore were to investigate the effect of MSCs on repair of the distal lung epithelium in normocapnia and hypercapnia in anin vitromodel of ARDS, and to assess the role of mitochondrial transfer in mediating the MSC effect.MethodsPrimary, human small airway epithelial cell (SAEC) monolayers were wounded in anin vitroscratch assay, stimulated with cytomix (IFN-gamma, I L-1 beta, TNF-alpha), and co-cultured with MSCs in normocapnia (5% CO2) or hypercapnia (15% CO2). Percentage wound closure was measured at 24 hour. SAEC proliferation was assessed by Ki67 staining. Mitochondrial transfer from MSCs to SAECs was assessed by flow cytometry using MitoTracker Green dye. MSC mitochondrial membrane potential was analysed by flow cytometry using JC-1. ATP production was measured by luminescent assay.ResultsEpithelial wound closure was impaired by hypercapnia. MSCs promoted epithelial wound closure in the inflammatory setting in normocapnia via enhanced migration. This reparative capacity was lost in hypercapnia. Mitochondrial transfer from MSCs to SAECs was observed to a similar extent in normocapnia and hypercapnia. However, hypercapnia attenuated mitochondrial membrane potential and ATP production in MSCs.ConclusionWhile they promote epithelial wound repair in an inflammatory environment in normocapnia, MSCs lose this ability in hypercapnia. This suggests that their therapeutic efficacy may be lost in such an environment. An inhibitory effect of hypercapnia on MSC mitochondrial function may be at least partially responsible for this effect.