Development of Full Thickness Human Skin Perfusion Model for Testing Medical Countermeasures against Radiation Induced Skin Injuries

项目摘要 皮肤是抵御外来侮辱和病原体的第一道防线，是第一个受到影响的器官 辐射事故。意外暴露、战时危险或与恐怖主义有关的事件的威胁一直是 由于工业、医疗设施和军事中放射性材料的使用增加而加剧 安装。皮肤对电离辐射的反应对局部和全身治疗具有重要意义 保护。目前，针对辐射引起的皮肤损伤的对策非常有限，而那些 都显示出有限的疗效。阻碍制定有效对策的一个关键因素是 缺乏对人类具有特定可译性的方便和健壮的模型。因此，这是我们的 长期目标是开发一种便携式组织培养生物反应器，能够保持全层细胞的活力 经动脉灌流的人皮瓣。利用这个生物反应器，我们将建立一个人体皮肤的体外模型 研究辐射导致皮肤损伤的潜在机制，并将随后测试其疗效 医学对策。我们的中心假设是由灌流生物反应器支持的人皮肤 将实现临床相关的长期(~4周)RI的表征和潜在的评估 治疗。RI有望通过局部治疗诱导DNA损伤、炎症和细胞凋亡 在人体皮肤灌流模型中应用JP4-039有望减轻这些影响。为了支持我们的 假设，我们的初步工作导致了可重复的灌流生物反应器的成功制造。这 生物反应器能够控制通过动脉进入的血管化皮肤组织中的持续液体流动 插管。该系统配备了对静脉和动脉血压的实时监测，并可以 根据解剖相关的输入动态调整体液流量。此外，实时反馈系统 用于保持常温的组件已安装，以及负责 测量气态二氧化碳、气态O2和灌流液pH值。使用这个灌流生物反应器，我们已经展示了 人皮瓣灌流成功。我们计划通过追求以下两个方面来测试我们的中心假设 明确的目标。目的1：体外全层人体皮肤灌流中放射性损伤的特征 文化。目的2-测试抗氧化剂JP4-039减轻辐射皮肤损伤的能力。这部小说 利用废弃人体皮肤组织进行力学研究及医学对策的探讨 抗辐射损伤有很大的希望。我们的团队在机器方面有丰富的经验 发展，整形和重建外科，辐射损伤的研究和发展 医学对策。我们预计，这一项目的成功完成将大大 促进我们对辐射引起皮肤损伤的机制的理解，并验证 使用我们的灌流培养模型作为测试医学对策的平台。

Project Summary Skin, being the first line of defense against foreign insults and pathogens, is the first organ to be affected by radiation incidents. The threat of accidental exposures, wartime hazards, or terrorism-related incidents has been intensified due to the increased use of radioactive materials in industry, medical facilities, and military installations. Skin response to ionizing radiations has important implications for local and systemic treatment and protection. Currently, there are very limited countermeasures for radiation-induced skin damage, and those that are available have shown limited efficacy. A key factor hindering development of effective countermeasures is the absence of a convenient and robust model possessing specific translatability to humans. It is therefore our long-term objective to develop a portable tissue culture bioreactor capable of maintaining viability of full-thickness human skin flaps via arterial perfusion. With this bioreactor, we will establish an in vitro human skin model for studying the underlying mechanism of radiation-induced skin damage and will subsequently test the efficacies of medical countermeasures. Our central hypothesis is that human skin supported by the perfusion bioreactor will enable clinically relevant, long-term (~4 weeks) characterization of RI and the assessment of potential therapies. RI is expected to induce DNA damage, inflammation, and apoptosis and treatment via topical application of JP4-039 is expected to mitigate these effects in human skin perfusion model. In support of our hypothesis, our preliminary work resulted in the successful fabrication of reproducible perfusion bioreactor. This bioreactor is capable of controlling continuous fluid flow throughout vascularized skin tissue, accessed via arterial cannulation. The system is equipped with real-time monitoring of venous and arterial pressures and can dynamically adjust the fluid flow based on anatomically-relevant inputs. Additionally, real-time feedback systems for maintenance of normothermic temperature have been installed, along with components responsible for measuring gaseous CO2, gaseous O2, and perfusate pH. Using this perfusion bioreactor, we have shown successful perfusion of human skin flap. We plan to test our central hypothesis by pursuing the following two specific aims. Aim 1- Characterize radiation induced injury in an ex vivo full-thickness human skin perfusion culture. Aim 2- Test the ability of antioxidant JP4-039 to mitigate radiation-induced skin damage. This novel approach to use discarded human skin tissue for mechanistic studies and develop medical countermeasures against radiation induced injuries holds a lot of promise. Our team has extensive experience in machine development, plastic and reconstructive surgeries, the study of radiation induced damage, and the development of medical countermeasures. We anticipate that the successful completion of this project will significantly advance our understanding of the mechanisms involved in radiation-induced skin damage as well as validate the use of our perfusion culture model as a platform of testing medical countermeasures.