Human Umbilical Cord as a Regenerative Meningeal Patch to Prevent Tethering and Improve Neurological Function Following In-Utero Spina Bifida Repair

摘要 接受宫内脊柱裂修复的儿童中，超过一半的人无法行走，超过四分之一的儿童 他们需要在学龄前对脊髓栓系进行手术。改善远期脊髓功能的方法 以及这些患者的共病情况，仍然难以捉摸。长期目标是发现宫内脊柱裂 解决改进方法的治疗方法，将促进神经学和 神经发育在生命的后期获得，从而从功能上调整患者的生活质量，使其变得更好。这个 本方案的目的是在绵羊模型系统中使用一种新的方法修复宫内脊柱裂，该模型 随着时间的推移，可能会比目前的修复方法对羔羊产生更有利的结果。一种冷冻保存的 人脐带(Huc)是一种来自健康足月妊娠的同种异体移植，在分娩后施加抗 炎症和抗疤痕特性，同义的关键过程，直接影响脊柱 将会发生绳索拴系，因此会产生长期结果。HUC目前正被FDA批准用于 眼科疾病。在我们的临床前研究中，我们已经表明，使用冷冻保存的人类 作为脑膜补片的脐带有助于蛛网膜层的再生，蛛网膜层是脊髓渗透的关键屏障 疤痕形成细胞，最终减少组织学上的束缚，改善脊髓功能。我们的中央 假设在宫内脊柱裂期间，Huc用作两层封闭的脑膜补片 修复，与传统修复或预测的生物材料相比，将改善长期临床结果。这 是根据我们的初步数据制定的，代表着脊柱裂治疗的重大进步 鉴于临床后遗症的改善，有可能垂直推进宫内治疗。其基本原理是 因为这项研究迫切需要一种抗瘢痕和再生的基质，这种基质可以放置在 作为脊髓和皮肤层之间的中间层，以减少拴系。中心假说将 通过在外科脊柱裂绵羊模型系统中追求三个特定目标进行测试：1) 比较使用HUC的宫内SB修复方法 谓词(DurepairTM)生物材料作为脑膜贴片。2)量化和比较长期空间和 3T对脊髓栓系、脊髓空洞症和炎症损伤修复部位脊髓时间变化的研究 磁共振成像和扩散张量成像。3)定量比较长期的潜在机制 SB缺陷修复方法的治疗效果。我们将通过创新的方式实现这些目标 自使用冷冻保存的人脐静脉以来，外科和生物处理技术的结合 CORD通过将重点转移到抗炎上，代表了对现状的新的实质性偏离， 脊柱裂脑膜复盖物的抗瘢痕及再生修复。其意义在于 这项工作的预期结果是，人脐带补片作为脑膜补片应该是可行的 脊柱裂修复的纵向治疗选择，并支持人类临床试验。

SUMMARY Over half the children who underwent in-utero spina bifida repair are unable to walk, and over one-fourth of them require surgery for tethered spinal cord by school age. Methods to improve long-term spinal cord function and its co-morbidities for these patients, remains elusive. The long-term goal is to find in-utero spina bifida treatment approaches that address refinement of methodologies that will promote neurological and neurodevelopmental gains later in life, thereby functionally adjusting patients’ quality of life for the better. The objective of this proposal is to use a new approach to repair spina bifida in-utero in a sheep model system, which may render more beneficial outcomes for lambs over time than current methods of repair. A cryopreserved human umbilical cord (HUC), an allograft from a healthy term pregnancy following delivery, exerts anti- inflammatory and anti-scarring properties, synonymously crucial processes that directly impact whether spinal cord tethering will occur, and hence long-term outcomes. The HUC is currently FDA approved for ophthalmological diseases. In our preclinical studies, we have shown that use of the cryopreserved human umbilical cord as a meningeal patch helps regenerate the arachnoid layer, a key barrier to spinal cord infiltrating scar forming cells, ultimately reducing histological tethering and improving upon spinal cord function. Our central hypothesis is that the HUC, when used as a meningeal patch with two-layer closure during in-utero spina bifida repair, will improve long-term clinical outcomes compared to conventional repair or predicated biomaterials. This was formulated based on our preliminary data, representing a significant advancement in spina bifida treatment given clinical sequelae improvements, with the potential to vertically advance in-utero treatment. The rationale for this study is that there is an urgent critical need for an anti-scarring and regenerative matrix that can be placed as an intermediary layer between the spinal cord and skin layer to reduce tethering. The central hypothesis will be tested by pursuing three specific aims in a surgical spina bifida sheep model system with a myelotomy: 1) To compare long-term functional outcome differences between in-utero SB repair methodologies using a HUC vs. predicate (DurepairTM) biomaterial as a meningeal patch. 2) To quantify and compare long-term spatial and temporal changes of the spinal cord at defect repair sites for tethering, syringomyelia and inflammation using 3T MRI and diffusion tensor imaging. 3) To quantitatively compare the underlying mechanisms for long-term therapeutic efficacies of SB defect repair methodologies. We will pursue these aims using an innovative combination of surgical and biological manipulative techniques, since use of the cryopreserved human umbilical cord represents a new and substantive departure from the status quo by shifting focus to the anti-inflammatory, anti-scarring and regenerative repair of the meningeal coverings of spina bifida. The significance lies in the expected outcome from this work, that the human umbilical cord patch as a meningeal patch should be a viable longitudinal therapeutic option for spina bifida repair and support a human clinical trial.