A novel bioengineered technique to rapidly and permanently repair cut PNS nerves

描述（由申请人提供）：一种快速和永久修复切断的PNS神经的新型生物工程技术我们的长期目标是性能优化，以将我们的新型和创新技术转化为临床应用，从而对急性和慢性切断的哺乳动物PNS轴突进行快速和永久修复，以恢复切断前它们介导的行为功能。我们应用了一个明确的序列的生物工程解决方案，含有聚乙二醇（PEG）和各种抗氧化剂或氧化剂，以快速和永久地重新加入（PEG融合）完全切断切断的大鼠坐骨神经轴突的末端作为模型在体内系统，使PEG融合的轴突是生理和形态完整的病变部位和它们的刺激恢复由完整的坐骨神经介导的行为功能。我们的轴突连续性的生理和形态学措施是动作电位传导和轴突内染料扩散穿过病变部位和EM和免疫组织化学分析。我们的行为恢复的措施是足故障不对称性测试和坐骨神经功能指数。我们通过冷却或环孢菌素A延缓沃勒变性，然后通过PEG融合修复慢性切断长达10天的轴突。我们优化了急性或慢性切除的坐骨神经节段的组织（生物相容性）反应，这些坐骨神经节段用作间位自体移植物或同种异体移植物，以PEG融合修复急性或慢性切割的大鼠坐骨神经。神经切断是人类PNS轴突的常见创伤性损伤。目前，各种手术略微改善了切断后重新建立连接的PNS轴突的数量和特异性，但没有改善PNS轴突重新建立这些连接的生长速度（约1 mm/天）或时间（数周至数年）。靶组织可能在神经再支配发生之前萎缩。因此，靶组织通常非特异性地重新神经支配，并且行为恢复通常很差。PEG融合显著提高了哺乳动物PNS轴突急性切割或挤压切断后行为恢复的速度和功效。我们还可以延迟切断的哺乳动物轴突的轴突沃勒变性长达10天，以增加切断后长达10天的成功PEG融合的时间，使得神经损伤不必立即治疗。我们精心设计的生物工程解决方案和PEG融合所需的材料仅使用FDA批准的化学品。因此，我们在大鼠坐骨神经上开发的PEG融合技术作为体内系统的模型，应迅速转化为临床程序。我们提出的R-01的结果具有很大的潜力，可以将当前研究和临床实践的重点从设计程序以增强缓慢轴突生长的结果转移到考虑通过我们的新型PEG融合技术进行快速修复。

DESCRIPTION (provided by applicant): A novel bioengineered technique to rapidly and permanently repair cut PNS nerves Our long term objective is to performance-optimize to translate for clinical use our novel and innovative technique to produce rapid and permanent repair of acutely and chronically severed mammalian PNS axons to restore the behavioral functions they mediated prior to severance. We apply a well-specified sequence of bioengineered solutions containing polyethylene glycol (PEG) and various anti-oxidizing or oxidizing agents to rapidly and permanently rejoin (PEG-fuse) completely cut-severed ends of rat sciatic axons as a model in vivo system so that PEG-fused axons are physiologically and morphologically intact through the lesion site and their stimulation restores behavioral functions mediated by intact sciatic nerves. Our physiological and morphological measures of axonal continuity are action potential conduction and intraaxonal dye diffusion across the lesion site and EM and immuno-histochemical analyses.. Our measures of behavioral restoration are Foot Fault Asymmetry test and Sciatic Functional Index. We retard Wallerian degeneration by cooling or cyclosporin A and then repair axons chronically severed for up 10 days by PEG-fusion. We performance optimize tissue (biocompatability) responses of acutely or chronically excised sciatic nerve segments that are used as inter- position autografts or allografts to PEG-fuse repair acutely or chronically cut rat sciatic nerves. Nerve severance is a common traumatic injury to PNS axons in humans. Various procedures currently slightly improve the number and specificity of PNS axons that reestablish connections following severance, but not outgrowth rate (~1mm/day) or time (weeks to years) for PNS axons to re-establish those connections. Target tissues may atrophy before re-innervation can occur. Consequently, target tissues are often non-specifically re-innervated and behavioral recovery is often poor. PEG-fusion dramatically improves the speed and efficacy of behavioral recovery following acute cut- or crush-severance of mammalian PNS axons. We can also retard axonal Wallerian degeneration of severed mammalian axons for up to 10 days to increase the time for successful PEG-fusion for up to 10 days post-severance so that nerve injuries do not have to be immediately treated. Our well-specified sequence of bio-engineered solutions and materials needed for PEG-fusion use only FDA-approved chemicals. Hence, our PEG-fusion technique developed on rat sciatic nerves as a model in vivo system should rapidly translate to clinical procedures. The results of our proposed R-01 have high potential for shifting the current emphasis of current research and clinical practice from devising procedures to enhance the results of slow axonal outgrowth to considering rapid repair by our novel PEG-fusion technique.