Development of Bioengineered Skeletal Muscle for Functional Replacement in vivo

描述(由申请人提供)： 由于先天性和获得性疾病，如创伤、肿瘤切除等，骨骼肌功能丧失会产生生理缺陷，目前仍没有有效的临床治疗方法。体外骨骼肌组织工程用于体内功能组织替代可能为这一未得到满足的医学需求提供潜在的治疗方案。为此，我们将使用我们已建立的方法，即将原代肌肉前体细胞(MPC)种植到基于胶原的无细胞组织支架上。这一方法将与两项使能技术相结合，以建立可以在临床上转化的功能性肌肉组织；第一，在定制设计的计算机控制的生物反应器系统中使用循环应变方案，第二，利用一种新型的产氧生物材料。第一项技术包括体外循环机械应变，导致体内骨骼肌收缩能力增强，第二项技术将评估支架中掺入产氧颗粒将允许肌肉组织延长存活的工作假设，直到体内建立宿主血管形成。因此，这项建议显然与PAR-06-504“组织工程和再生医学的使能技术(R01)”一致。为了实现我们在体内增加生物工程骨骼肌组织功能和质量的长期目标，我们建议逐步增加生物工程肌肉组织结构的大小和复杂性；时间从植入后1-16周不等。我们将使用从整个组织到单一纤维、分子和遗传水平的多学科方法，在体外和体内监测和评估组织工程构建物的表型和功能成熟情况。我们将利用背阔肌功能替代模型的独特功能来评估我们的使能技术实现接近天然骨骼肌的生物工程骨骼肌的能力。 具体目的#1：评估生物反应器预适应和颗粒氧发生器(POGS)对植入背阔肌(LD)的骨骼肌的形成和功能的影响(1-2岁)。 具体目标#2：应用生物工程骨骼肌功能替代小鼠背阔肌模型中的小缺陷：“概念证明”(第2-3年)。具体目标#3：开发用于小鼠LD模型大缺陷的功能替代的生物工程骨骼肌：“临床适用性评估”(第4-5年)。 公共卫生相关声明(由申请人提供)：由于先天和后天条件，如创伤、肿瘤切除等，导致骨骼肌功能丧失，导致生理缺陷，目前仍没有有效的临床治疗方法。体外骨骼肌组织工程用于体内功能组织替代可能为这一未得到满足的医学需求提供潜在的治疗方案。

DESCRIPTION (provided by applicant): Loss of functional skeletal muscle due to congenital and acquired conditions, such as traumatic injury, tumor excision, etc., produces a physiological deficit for which there is still no effective clinical treatment. Tissue engineering of skeletal muscle in vitro for functional tissue replacement in vivo may provide a potential therapeutic solution to this unmet medical need. To this end, we will use our established approach in which primary muscle precursor cells (MPCs) are seeded onto collagen-based acellular tissue scaffolds. This approach will be combined with two enabling technologies to build functional muscle tissue that could be translated clinically; first, a cyclic strain protocol in a custom designed, computer-controlled bioreactor system, and second, utilization of a novel class of oxygen generating biomaterials. The first technology consists of cyclic mechanical strain in vitro leading to enhanced skeletal muscle contractility in vivo, while the second will evaluate the working hypothesis that incorporation of oxygen generating particles in the scaffold will permit prolonged muscle tissue survival until host vascularization is established in vivo. As such, this proposal is clearly consistent with PAR-06-504 "Enabling Technologies for Tissue Engineering and Regenerative Medicine (R01)". To achieve our long-term goal of increased bioengineered skeletal muscle tissue function and mass in vivo, we propose a step-wise increase in size and complexity of the bioengineered muscle tissue constructs; for time points ranging from 1-16 weeks post-implantation. We will monitor and assess the phenotypic and functional maturation of the tissue engineered constructs both in vitro and in vivo, using a multidisciplinary approach (on both engineered and native tissue from the same animal) ranging from the whole tissue to the single fiber, molecular and genetic levels. We will leverage the unique features of the latissimus dorsi functional replacement model to evaluate the ability of our enabling technologies to achieve bioengineered skeletal muscle that approximates native skeletal muscle. Specific Aim #1: To evaluate the impact of bioreactor preconditioning and particulate oxygen generators (POGs) on the formation and function of skeletal muscle implanted onto the latissimus dorsi (LD) in vivo (Years 1-2). Specific Aim #2: Application of bioengineered skeletal muscle for functional replacement in a small defect in a mouse latissimus dorsi model: "Proof of Concept" (Years 2-3). Specific Aim #3: Development of bioengineered skeletal muscle for functional replacement in a large defect in a mouse LD model: "Evaluation of clinical applicability" (Years 4-5). Public Health Relevance Statement (provided by applicant): Loss of functional skeletal muscle due to congenital and acquired conditions, such as traumatic injury, tumor excision, etc., produces a physiological deficit for which there is still no effective clinical treatment. Tissue engineering of skeletal muscle in vitro for functional tissue replacement in vivo may provide a potential therapeutic solution to this unmet medical need.