Cell survival in engineered skeletal muscle: The role of complement

摘要 由于创伤、肿瘤切除或先天性畸形导致的肌肉损失对患者及其家属是毁灭性的。 家人目前的治疗方案包括创造性地重新安排皮肤和肌肉瓣，以减轻 畸形然而，这些方法通常是次优的，因为移动的皮瓣组织收缩的百分比， 萎缩和/或死亡并且不像原始组织那样起作用。该领域长期以来一直设想一种治疗方式 用病人自己的细胞制造组织移植物，然后移植到病人体内， 形式和功能。然而，不幸的是，这种新的治疗方法还有许多障碍需要克服。 计划在临床上广泛采用。一个紧迫而未被充分认识的障碍是， 我们假设这些细胞被对植入移植物的先天免疫反应杀死。一个主要 先天免疫的效应机制是补体（Cp）系统。早期Cp炎症的程度 杀死TEC内大量细胞的事件仍然是组织中一个重要的未回答的问题- 工程领域。即使可以避免由于早期炎症引起的细胞死亡， 支持.产生具有快速吻合潜力的预血管化TEC的技术将 显著改善细胞存活和移植。这两个突出的事件密切相关。 在没有早期血管支持或存在血管支持的情况下减少早期炎症 大量炎症反应仍将导致细胞死亡和修复失败。因此，我们的中心假设 Cp效应子通路的调节将通过减少炎症、直接抑制肿瘤细胞增殖、 细胞损伤和促进新生血管形成。在这份提案中，我们阐明了一条调查路线， 导致一种使能技术，通过调节细胞化植入物的早期 炎症过程和促进新生微血管床。我们的实验室发明了新的策略， 针对早期炎症反应的治疗方法。此外，我们最近开发了一种新的 无支架技术制备自组织预血管化内皮成纤维细胞构建体 （规格）。这些工程结构一旦植入，就可以很快地被血液灌注。使用 作为我们的指导，我们将系统地测试已知的炎症，血管生成和吻合机制， 这些创新技术使用特定的抑制剂和基因工程小鼠在肌肉下植入， 模型预期成果将通过提供可行的解决办法，大大推动该领域的工作 组织工程面临的主要障碍-快速血管化和植入细胞的存活 和纸巾。

Abstract Muscle loss due to trauma, tumor resection or congenital malformation is devastating to the patient and their family. Current treatment regimens involve creative rearrangement of skin and muscle flaps to mitigate the deformity. However, these approaches are often sub-optimal as a percentage of mobilized flap tissues contract, atrophy and/or die and do not function like the original tissues. The field has long envisioned a treatment modality where using the patient's own cells to create tissue grafts, that can then be transplanted into a patient to restore form and function. However, unfortunately, there are numerous hurdles yet to be overcome for this new treatment plan to be broadly adopted in the clinic. One urgent and underappreciated hurdle is the poor survival rate of implanted cells which we hypothesize are killed by the innate immune response to the implanted graft. A major effector mechanism of innate immunity is the complement (Cp) system. The extent that early Cp inflammatory events kill a substantial number of cells within the TECs remains an important unanswered question in the tissue- engineering field. Even if cell death due to early inflammation can be avoided, there is insufficient vascular support. Techniques to generate pre-vascularized TECs which have rapid anastomotic potential would substantially improve cell survival and engraftment. These two highlighted events are intimately linked. Reduction of early inflammation without early vascular support or early vascular support in the presence of a substantial inflammatory response will still result in cell death and failed repair. Therefore, our central hypothesis is that; modulation of Cp effector pathways will promote survival of TEC by reducing inflammation, direct cell injury, and by promoting neovascularity. In this proposal we articulate a line of investigation that will lead to an enabling technology to improve the engraftment of cellularized implants by modulating the early inflammatory process and promoting nascent microvascular beds. Our lab has invented novel strategies and therapeutics that target the early inflammatory response. Additionally, we have recently developed a novel scaffold-free technology to generate Self-organizing Pre-vascularized Endothelial-fibroblast Constructs (SPECs). These engineered constructs can become perfused with blood very quickly once implanted. Using known mechanisms of inflammation, angiogenesis and anastomosis as our guide, we will systematically test these innovative technologies using specific inhibitors and genetically engineered mice in a sub-muscular implant model. The expected outcomes would significantly move the field forward by providing a workable solution to the principal hurdles facing tissue engineering - rapid vascularization and survival of implanted cells and tissues.