Laser Treatment Modality for Strengthening Osteoarthritic Cartilage

项目摘要 骨关节炎（OA）是一种使人衰弱的退行性疾病，估计有2700万25岁的美国人患有这种疾病 年纪也更大了这种疾病导致双关节的关节层的进行性退化， 显著损害软骨作为承重材料的主要功能，导致疼痛和限制 日常生活活动。直到今天，减缓进展的治疗选择非常有限 OA的早期阶段大多数治疗，如高度侵入性的部分和全关节置换手术 都是在疾病晚期进行的将治疗方案引入OA的早期阶段， 延迟或减缓疾病进展的潜力，从而显著改善患者结局。的 关节软骨的主要功能是在关节表面传递载荷 最小化摩擦和磨损。本申请描述了一种基于超快激光的治疗方法的发展 工具，其具有在不添加交联剂的情况下将交联诱导到软骨胶原网络中的能力。 化学试剂，同时避免光学击穿和烧蚀的破坏作用。初步 数据表明，激光诱导的交联增加了压缩刚度和耐磨性， 损害细胞活力，这可能预期会减缓OA的进展。其总体目标是 应用是开发一系列有效和安全的激光操作参数， 机械性能和耐磨性，使我们能够产生临床相关的协议。我们还旨在 为了评估激光诱导的活性氧短寿命爆发对长期 软骨在体外和体内培养过程中的反应。将这项技术应用到未来的动物身上， 人类研究，我们将开发和测试一种基于激光的临床工具，用于关节镜治疗软骨， 原地。在具体目标1中，我们将优化用于结构、形态和功能修饰的框架， 使用灭活牛和人，对软骨细胞外基质进行飞秒激光照射， OA软骨外植体。在具体目标2中，我们将通过测试短期 激光处理的活牛和人OA（雄性和雌性）软骨外植体的长期存活率 未处理的对照，使用体外培养长达4周。在具体目标3中，我们将验证激光处理的活 人OA软骨外植体在植入时表现出与未处理对照相当的活力和健康， 在裸鼠背部长达8周。我们还将制作一个基于光纤的激光系统，并验证其 在OA膝关节中模拟原位关节镜应用的有效性。在完成这些 研究，我们将建立这种新型激光治疗的有效和安全的操作参数 模式，并创造了一个实用的工具来测试这种方法在原位，首先在大型动物，然后在人类。

Project Summary Osteoarthritis (OA) is a debilitating degenerative disease that afflicts an estimated 27 million Americans age 25 and older. This disease leads to the progressive degradation of the articular layers of diarthrodial joints, significantly compromising the main function of cartilage as a load bearing material, leading to pain and limiting activities of daily living. To this day, there are very limited treatment options for slowing down the progression of OA in its early stages. Most therapies, such as highly invasive partial and total joint replacement surgeries are performed at the late stage of the disease. Introducing treatment options to earlier stages of OA presents the potential to retard or slow down disease progression and thus significantly improve patient outcomes. The primary function of articular cartilage is to transmit loads across the joint surfaces while simultaneously minimizing friction and wear. This application describes the development of an ultrafast laser-based treatment tool which has the ability to induce crosslinks into the cartilage collagen network without the addition of a chemical agent, while simultaneously avoiding damaging effects of optical breakdown and ablation. Preliminary data show that laser-induced crosslinks increase compressive stiffness and wear resistance, without compromising cell viability, which may be expected to slow down progression of OA. The overall aim of this application is to develop a range of effective and safe laser operating parameters that enhance cartilage mechanical properties and wear resistance, enabling us to produce a clinically relevant protocol. We also aim to assess the influence of laser-induced short-lived bursts of reactive oxygen species onto the long-term response of cartilage during in vitro and in vivo culture. To translate this technology to future animal and human studies, we will develop and test a laser-based clinical tool for arthroscopic treatment of cartilage in situ. In specific aim 1, we will optimize a framework for structural, morphological and functional modification of the cartilage extracellular matrix subject to femtosecond laser irradiation, using devitalized bovine and human OA cartilage explants. In specific aim 2, we will narrow this range of operating parameters by testing short-term and long-term viability of laser-treated live bovine and human OA (male & female) cartilage explants against untreated controls, using in vitro culture up to 4 weeks. In specific aim 3, we will verify that laser-treated live human OA cartilage explants exhibit comparable viability and health as untreated controls when implanted for up to 8 weeks in the back of nude mice. We will also fabricate a fiber optic-based laser system and validate its effectiveness in simulated in situ arthroscopic applications in OA knee joints. Upon completion of these studies, we will have established effective and safe operating parameters for this novel laser treatment modality, and created a practical tool to test this methodology in situ, first in large animals, then in humans.