Synthetic hydrogel for satellite cell delivery to the dystrophic diaphragm

摘要 Duchenne肌营养不良症是一种X连锁遗传疾病，会导致虚弱的健康后果。多数 受影响的患者无法活过他们的成年早期，主要是由于呼吸道并发症(例如， 呼吸、肺炎和肺不张)，由横隔肌恶化引起。当前呼吸系统 护理疗法，如机械辅助呼吸，仍然是一种姑息疗法和有效的治疗策略 以横隔肌为靶点恢复呼吸能力是一种迫切的需要。这个项目的目标是 是开发一种生物材料介导的策略，将肌肉卫星细胞运送并植入横隔膜，以 通过恢复dystrophin、兴奋-收缩偶联来恢复呼吸功能 机械稳定性。这一目标将通过以下方式实现：(1)设计一种能够 在3D中维持和指导肌肉卫星细胞的功能，以及(2)将封装在 经过改造的生物材料可以刺激供体细胞的植入，从而挽救肌营养不良蛋白的表达， 幼年(2月龄)和幼年(2月龄)营养不良横隔肌的神经肌肉连接形成和收缩功能 老龄(12月龄)mdx/mtr小鼠。指导这个项目的中心假设是工程利基- 含有旨在增加卫星细胞黏附、存活、增殖和分化的生物材料，将 能够精确地将细胞输送到横隔膜的下表面，增强随后的局部细胞保持， 供体细胞的存活、扩增、迁移和植入，并进一步为 老化/萎缩的营养不良横隔膜。这项工作的结果将对推进呼吸 杜氏肌营养不良症的治疗策略。抢救衰竭的横隔肌，以及 从而对呼吸功能，将积极影响患者的健康寿命和生活质量提供 有机会绕过机械辅助通风的需要。这项工作的圆满完成将 也提供了一个机会，进一步协同这一平台与诱导的多能干细胞和紧急 基因编辑技术用于治疗各种形式的糖尿病患者的隔膜功能 神经肌肉疾病。

ABSTRACT Duchenne muscular dystrophy is an X-linked genetic disorder that begets debilitating health consequences. Most affected patients do not live past their early adulthood primarily due to respiratory complications (e.g., decreased breathing, pneumonia and atelectasis) caused by deterioration of the diaphragm muscle. Current respiratory care therapies, such as mechanically assisted ventilation, remain palliative, and an effective therapeutic strategy targeting the diaphragm muscle to restore the respiratory capacity is a critical need. The objective of this project is to develop a biomaterial-mediated strategy to deliver and engraft muscle satellite cells to the diaphragm to reinstate the respiratory function through restoration of dystrophin, excitation-contraction coupling, and mechanical stability. This objective will be achieved by (1) engineering a synthetic biomaterial that is capable of maintaining and directing muscle satellite cell function in 3D and (2) delivering satellite cells encapsulated in the engineered biomaterial to stimulate engraftment of donor cells, thereby rescuing dystrophin expression, neuromuscular junction formation, and contractile function of the dystrophic diaphragm of young (2 months) and aged (12 months) mdx/mTR mice. The central hypothesis guiding this project is that the engineered niche- containing biomaterial designed to increase satellite cell adhesion, survival, proliferation, and differentiation will enable precise delivery of cells to the inferior surface of the diaphragm, enhance subsequent local cell retention, survival, expansion, migration, and engraftment of the donor cells, and further provide mechanical support to the aged/atrophied dystrophic diaphragm. The outcomes of this work will be significant in advancing the respiratory treatment strategy in the context of Duchenne muscular dystrophy. Salvaging the failing diaphragm muscle, and thereby the respiratory function, will positively impact patients healthspan and quality of life by providing opportunities to bypass the need for mechanically assisted ventilation. Successful completion of this work will also provide an opportunity to further synergize this platform with induced pluripotent stem cells and emergent gene editing technologies to treat diseased diaphragm function of patients suffering from various forms of neuromuscular diseases.