Stem cell therapies have gained great attention for providing novel solutions for treatment of various injuries and diseases due to stem cells’ self-renewal, ability to differentiate into various cell types, and favorite paracrine function. Nevertheless, the low retention of transplanted stem cell still limits their clinical applications such as in wound healing in view of an induced harsh microenvironment rich in reactive oxygen species (ROS) during inflammatory reactions. Herein, a novel chitosan/acellular dermal matrix (CHS/ADM) stem cell delivery system is developed, which is of great ROS scavenging activity and significantly attenuates inflammatory response. Under ROS microenvironment, this stem cell delivery system acts as a barrier, effectively scavenging an amount of ROS and protecting mesenchymal stem cells (MSCs) from the oxidative stress. It notably regulates intracellular ROS level in MSCs and reduces ROS-induced cellular death. Most importantly, such MSCs delivery system significantly enhances in vivo transplanted stem cell retention, promotes the vessel growth, and accelerates wound healing. This novel delivery system, which overcomes the limitations of conventional plain collagen-based delivery system in lacking of ROS-environmental responsive mechanisms, demonstrates a great potential use in stem cell therapies in wound healing.

中文翻译：

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防止活性氧的屏障：壳聚糖/无细胞真皮基质支架可增强干细胞保留能力，并改善皮肤伤口愈合。

干细胞疗法因提供新颖的解决方案来治疗各种损伤和疾病而引起了极大的关注，这些解决方案是由于干细胞的自我更新，能够分化为各种细胞类型以及最喜欢的旁分泌功能而引起的。然而，考虑到在炎症反应过程中诱导出的富含活性氧（ROS）的恶劣微环境，移植的干细胞的低保留率仍然限制了其临床应用，例如在伤口愈合中。本文中，开发了一种新型的壳聚糖/无细胞真皮基质（CHS / ADM）干细胞递送系统，该系统具有强大的ROS清除活性并显着减弱炎症反应。在ROS微环境下，这种干细胞递送系统充当屏障，有效清除一定量的ROS，保护间充质干细胞（MSCs）免受氧化应激。它特别调节MSC中的细胞内ROS水平并减少ROS诱导的细胞死亡。最重要的是，这种MSCs递送系统显着增强了体内移植的干细胞保留能力，促进了血管生长，并加速了伤口愈合。这种新颖的输送系统克服了传统的基于胶原蛋白的普通输送系统在缺乏ROS环境响应机制方面的局限性，证明了在干细胞治疗伤口愈合中的巨大潜力。并加速伤口愈合。这种新颖的输送系统克服了传统的基于胶原蛋白的常规输送系统在缺乏ROS环境响应机制方面的局限性，证明了在干细胞治疗伤口愈合中的巨大潜力。并加速伤口愈合。这种新颖的输送系统克服了传统的基于胶原蛋白的普通输送系统在缺乏ROS环境响应机制方面的局限性，证明了在干细胞治疗伤口愈合中的巨大潜力。