Use Of Adipose Derived Stem Cells For Engineering Of Ligament Tissue

描述（由申请人提供）： 摘要： 前交叉韧带（ACL）断裂是膝关节最常见的韧带损伤之一，常见于VA患者人群。在美国，每年大约有102，000例需要手术。 ACL是膝关节的重要稳定器，其完整性是许多日常生活和体育活动所必需的。 在许多退伍军人中，ACL是高尔夫球和垒球等娱乐性体育活动所必需的，在一些患者中，ACL是日常生活活动所必需的，包括步行。 当受伤时，它的缺失会导致膝关节不稳定，通常需要进行活动调整以避免症状性不稳定。 此外，有证据表明，如果不治疗，膝关节会恶化。 因此，ACL损伤的治疗旨在恢复膝关节稳定性，以防止复发性不稳定的相关并发症，随后对膝关节和关节软骨造成损伤。 目前ACL断裂的治疗需要使用移植物进行重建，因为受伤的ACL几乎没有愈合能力。目前的移植选择包括使用自体移植物（从膝盖的另一个未受伤部分获得的组织）或同种异体移植物（从尸体供体获得的组织）。由于使用这些移植物的固有缺点，使用组织工程化ACL移植物替代物将是有利的。 我们目前正在研究如何在体外完成这一过程，以便以后在体内植入。 本项目的总体目标是开发一种方法，用于用自体细胞接种合成支架，在体外适当条件下培养细胞接种的构建体，并最终将其植入用于膝关节韧带重建。 这种方法可以极大地改变膝关节韧带损伤的治疗，并避免目前使用自体移植物和同种异体移植物组织所遇到的缺点和风险。 该项目将利用一种新型的生物反应器，其中用电纺纤维制成的聚合物支架与人类脂肪来源的干细胞一起接种，将在体外受到机械刺激和生长因子的作用，作为产生新韧带组织的初步步骤，该组织随后可以植入韧带重建。 我们希望最终能够设计出用于ACL重建的强有力的新韧带，并且可以避免与自体移植物和同种异体移植物的使用相关的额外发病率。 此外，这种组织工程方法可能会缩短此类手术后康复所需的时间。 公共卫生相关性： 项目叙述 对退伍军人医疗保健的潜在影响：由于需要手术重建的膝关节韧带损伤在VA患者人群中很常见，因此该提案有可能直接影响退伍军人的生活，从而提高VA提供的服务质量。 尽管目前的ACL重建方法在恢复膝关节稳定性方面是成功的，但手术重建存在许多副作用和风险，主要是由于使用了重建受损韧带所需的移植物。 事实上，许多患有这种损伤的退伍军人因这个问题而被拒绝手术，因此必须减少他们的体力活动水平，因为移植物收获的发病风险是不合理的，并且目前没有足够的同种异体移植物可供每个人使用。 仅在我们的VA机构，在过去6年中就进行了150多例ACL重建。因此，该建议可以改善退伍军人ACL损伤的管理。 此外，本研究中开发的韧带和肌腱组织工程的基本方法可以直接应用于肌腱或韧带组织缺失或缺陷的其他常见临床问题。 这些问题包括肩（肩袖）和膝（四头肌和髌骨）肌腱断裂，这在VA患者人群中也很常见。 此外，本研究的结果可以应用于其他结缔组织的工程，包括其他肌腱，筋膜和皮肤。 因此，这项建议最终可能会大大改善退伍军人的生活质量。

DESCRIPTION (provided by applicant): Abstract: Rupture of the anterior cruciate ligament (ACL) is one of most common ligament injuries of the knee and is often seen in the VA patient population. There are approximately 102,000 cases requiring surgery each year in the United States. The ACL is an important stabilizer of the knee and its integrity is required for many activities of daily living and sporting activities. In many veterans, the ACL is necessary for recreational sporting activities such as golf and softball and in some patients it is necessary for activities of daily living including walking. When injured, its absence leads to knee instability and often necessitates activity modifications in order to avoid symptomatic instability. In addition, there is evidence to suggest the knee joint will deteriorate if left untreated. Thus, the treatment of ACL injuries is aimed at restoring knee stability to prevent the associated complications of recurrent instability with subsequent damage to the menisci and articular cartilage. Current treatments for ACL ruptures require the use of grafts for reconstruction because the injured ACL has little healing capacity. Current graft options include the use of either autografts (tissue obtained from another uninjured part of the knee) or allografts (tissue obtained from a cadaver donor). Because of the inherent disadvantages with the use of these grafts, it would be advantageous to use a tissue- engineered ACL graft substitute. We are currently investigating ways that this could be accomplished in vitro for later implantation in vivo. The overall goal of this project is to develop a method for seeding a synthetic scaffold with autologous cells, cultivating the cell seeded construct under appropriate conditions in vitro and ultimately implanting it for knee ligament reconstruction. This approach could vastly change the treatment of knee ligament injuries and avoids the disadvantages and risks encountered with the current use of autograft and allograft tissue. This project will utilize a novel bioreactor in which polymer scaffolds created with electrospun fibers seeded with human adipose derived stem cells will be subjected to mechanical stimuli and growth factors in vitro as a preliminary step towards generating neoligament tissue which could later be implanted for ligament reconstruction. We hope to eventually engineer strong neoligaments for ACL reconstruction and the added morbidity associated with the use of autografts and allografts could be avoided. In addition, such a tissue engineering approach could potentially shorten the time necessary for rehabilitation following this type of surgery. PUBLIC HEALTH RELEVANCE: Project Narrative Potential Impact on Veterans Health Care: Because knee ligament injuries which require surgical reconstruction are common in the VA patient population, this proposal has the potential to directly influence the lives of veterans and thereby enhance the quality of services provided by the VA. Although current methods for ACL reconstruction are successful at restoring stability to the knee, there are many side effects and risks to surgical reconstruction due primarily to the use of a graft which is needed to rebuild the injured ligament. In fact, many veterans with this injury are denied surgery for this problem and thus must decrease their physical activity level because the risk of morbidity from the graft harvest is not justified and there are not enough allografts currently available for everyone with this problem. At our VA institution alone, over 150 ACL reconstructions have been performed over the last 6 years. Thus, this proposal can improve the management of ACL injuries in veterans. In addition, basic methods of ligament and tendon tissue engineering developed in this study could be directly applied to other common clinical problems in which tendon or ligament tissue is absent or deficient. These problems include shoulder (rotator cuff) and knee (quadriceps and patellar) tendon ruptures, which are also common in the VA patient population. Furthermore, the results of this research could be applied to engineering of other connective tissues including other tendons, fascia, and skin. Thus, this proposal could ultimately result in substantial improvements in the quality of life of veterans.