Sakellariou Paraskevi, O'Neill Andrea, Mueller Amber L, Stadler Guido, Wright Woodring E, Roche Joseph A, Bloch Robert J
Department of Physiology, University of Maryland School of Medicine, 655 W. Baltimore St., Baltimore, MD 21201 USA.
Present address: FAME Laboratory, School of Exercise Science, University of Thessaly, Karies, Trikala, 42100 Greece.
Skelet Muscle. 2016 Feb 27;6:4. doi: 10.1186/s13395-016-0078-6. eCollection 2016.
Studies of the pathogenic mechanisms underlying human myopathies and muscular dystrophies often require animal models, but models of some human diseases are not yet available. Methods to promote the engraftment and development of myogenic cells from individuals with such diseases in mice would accelerate such studies and also provide a useful tool for testing therapeutics. Here, we investigate the ability of immortalized human myogenic precursor cells (hMPCs) to form mature human myofibers following implantation into the hindlimbs of non-obese diabetic-Rag1 (null) IL2rγ (null) (NOD-Rag)-immunodeficient mice.
We report that hindlimbs of NOD-Rag mice that are X-irradiated, treated with cardiotoxin, and then injected with immortalized control hMPCs or hMPCs from an individual with facioscapulohumeral muscular dystrophy (FSHD) develop mature human myofibers. Furthermore, intermittent neuromuscular electrical stimulation (iNMES) of the peroneal nerve of the engrafted limb enhances the development of mature fibers in the grafts formed by both immortal cell lines. With control cells, iNMES increases the number and size of the human myofibers that form and promotes closer fiber-to-fiber packing. The human myofibers in the graft are innervated, fully differentiated, and minimally contaminated with murine myonuclei.
Our results indicate that control and FSHD human myofibers can form in mice engrafted with hMPCs and that iNMES enhances engraftment and subsequent development of mature human muscle.
对人类肌病和肌肉萎缩症潜在致病机制的研究通常需要动物模型，但某些人类疾病的模型尚未可得。促进患有此类疾病个体的肌源性细胞在小鼠体内植入和发育的方法将加速此类研究，并且还为测试治疗方法提供有用的工具。在此，我们研究了永生化人类肌源性前体细胞（hMPCs）植入非肥胖糖尿病-Rag1（缺失）IL2rγ（缺失）（NOD-Rag）免疫缺陷小鼠后肢后形成成熟人类肌纤维的能力。
我们报告称，经X射线照射、用心脏毒素处理，然后注射永生化对照hMPCs或来自面肩肱型肌营养不良症（FSHD）个体的hMPCs的NOD-Rag小鼠后肢会发育出成熟的人类肌纤维。此外，对植入肢体的腓总神经进行间歇性神经肌肉电刺激（iNMES）可增强两种永生化细胞系形成的移植物中成熟纤维的发育。对于对照细胞，iNMES增加了形成的人类肌纤维的数量和大小，并促进了纤维间更紧密的排列。移植物中的人类肌纤维接受神经支配、完全分化，并且极少被小鼠肌核污染。
我们的结果表明，在植入hMPCs的小鼠中可以形成对照和FSHD人类肌纤维，并且iNMES可增强成熟人类肌肉的植入和后续发育。
