Madden Lauran, Juhas Mark, Kraus William E, Truskey George A, Bursac Nenad
Department of Biomedical Engineering, Duke University, Durham, United States.
Department of Medicine, Duke University School of Medicine, Durham, United States.
Elife. 2015 Jan 9;4:e04885. doi: 10.7554/eLife.04885.
Existing in vitro models of human skeletal muscle cannot recapitulate the organization and function of native muscle, limiting their use in physiological and pharmacological studies. Here, we demonstrate engineering of electrically and chemically responsive, contractile human muscle tissues ('myobundles') using primary myogenic cells. These biomimetic constructs exhibit aligned architecture, multinucleated and striated myofibers, and a Pax7(+) cell pool. They contract spontaneously and respond to electrical stimuli with twitch and tetanic contractions. Positive correlation between contractile force and GCaMP6-reported calcium responses enables non-invasive tracking of myobundle function and drug response. During culture, myobundles maintain functional acetylcholine receptors and structurally and functionally mature, evidenced by increased myofiber diameter and improved calcium handling and contractile strength. In response to diversely acting drugs, myobundles undergo dose-dependent hypertrophy or toxic myopathy similar to clinical outcomes. Human myobundles provide an enabling platform for predictive drug and toxicology screening and development of novel therapeutics for muscle-related disorders.
现有的人类骨骼肌体外模型无法重现天然肌肉的组织结构和功能，限制了它们在生理学和药理学研究中的应用。在此，我们展示了利用原代成肌细胞构建具有电响应和化学响应能力的收缩性人类肌肉组织（“肌束”）的工程方法。这些仿生构建体呈现出排列整齐的结构、多核且有横纹的肌纤维以及一个Pax7(+)细胞池。它们能自发收缩，并对电刺激产生单收缩和强直收缩反应。收缩力与GCaMP6报告的钙反应之间的正相关关系使得能够对肌束功能和药物反应进行非侵入性追踪。在培养过程中，肌束维持功能性乙酰胆碱受体，并且在结构和功能上成熟，这表现为肌纤维直径增加、钙处理能力改善以及收缩强度提高。在对不同作用的药物作出反应时，肌束会出现剂量依赖性肥大或毒性肌病，类似于临床结果。人类肌束为预测性药物和毒理学筛选以及开发针对肌肉相关疾病的新型疗法提供了一个有利平台。
