Neutralizing the degenerate disc microenvironment to enhance the efficacy of therapeutic stem cells

摘要 在美国，腰痛是导致残疾的主要原因，估计会造成社会经济损失 每年超过1000亿美元。椎间盘退变，一系列细胞，成分， 结构和成分的改变，是腰痛的一个重要原因。当前临床 治疗与椎间盘退变相关的下腰痛的方法长期疗效有限，因为 他们只寻求管理症状，而不是恢复固有的椎间盘结构和机械功能。的确有 压倒性的临床需求需要新的治疗方案，这些方案不仅针对低血压的症状 背部疼痛，也是根本原因。间充质干细胞(MSCs)是一种有吸引力的细胞移植选择。 基于椎间盘的再生，因为它们安全、易于分离，并且能够采用与那些 髓核细胞。然而，成功地基于MSC的光盘再生的一个主要挑战是 局部细胞微环境，呈现营养受限、低氧、低pH和 使治疗干预失败的持续性炎症。这项提议的目标是 开发一种新的生物疗法，最大限度地提高治疗性疾病的存活率和合成代谢潜力 干细胞通过持续的中和同时中和退化的椎间盘微环境 运送营养素、消炎药和缓冲剂。为了实现这一目标，我们将 利用我们新建立的模拟临床相关的椎间盘退变山羊模型 结构、成分和生物力学特征，包括组织水平的炎症 能够控制和持续释放中和生物因子的新型药物输送方法 退化的微环境。在目标1中，我们将利用我们的山羊模型定义体内细胞 椎间盘微环境作为退变严重程度的函数，使用尖端原位生理学方法 监测和体外生物分子分析。在目标2中，我们将优化我们的新型微胶囊药物输送 系统通过持续输送葡萄糖中和退化的视盘微环境，抗 发炎药和缓冲剂。在目标3中，我们将进行短期和长期的活体研究 在我们的山羊模型中建立治疗效果，包括与临床相关的疼痛评估。在 总结这些研究，我们将开发出一种快速翻译的疗法，使 骨髓间充质干细胞在椎间盘微环境中的再生潜能，并建立了长期的临床前研究 疗效，从而使我们处于迈向人类临床试验的有利地位。

Abstract Low back pain is the leading cause of disability in the United States, with an estimated socioeconomic cost exceeding $100 billion each year. Intervertebral disc degeneration, a cascade of cellular, compositional, structural and compositional changes, is strongly implicated as a cause of low back pain. Current clinical approaches for treating low back pain associated with disc degeneration have limited long term efficacy as they seek only to manage symptoms without restoring native disc structure and mechanical function. There is an overwhelming clinical need for new treatment options, which target not only the symptoms of low back pain, but also the underlying causes. Mesenchymal stem cells (MSCs) are an attractive option for cell- based disc regeneration due to their safety, ease of isolation and ability to adopt phenotypes similar to those of disc nucleus pulposus cells. A major challenge to successful MSC-based disc regeneration, however, is the local cellular microenvironment, which presents conditions of limited nutrition, low oxygen, low pH, and persistent inflammation that predispose therapeutic interventions to failure. The objective of this proposal is to develop a novel biological therapy that maximizes the survival and anabolic potential of therapeutic stem cells by simultaneously neutralizing the degenerate disc microenvironment via the sustained delivery of nutrients, anti-inflammatory drugs and buffering agents. To accomplish this goal, we will leverage our newly established goat model of disc degeneration that mimics clinically relevant structural, composition and biomechanical characteristics, including tissue-level inflammation, and novel drug delivery methods to enable controlled and sustained release of biofactors that neutralize the degenerative microenvironment. In Aim 1 we will leverage our goat model define the in vivo cellular microenvironment of the disc as a function of degeneration severity, using cutting edge in situ physiological monitoring and ex vivo biomolecular assays. In Aim 2 we will optimize our novel microcapsule drug delivery system to neutralize the degenerate disc microenvironment through sustained delivery of glucose, anti- inflammatory drugs and buffering agents. In Aim 3 we will carry out short and long term in vivo studies to establish therapeutic efficacy in our goat model, including clinically-relevant pain assessments. At the conclusion of these studies we will have developed a rapidly translatable therapy that maximizes the regenerative potential of MSCs in the disc microenvironment, and established long term preclinical efficacy, thus placing us in a strong position to move towards human clinical trials.