University of California, San Francisco.
Arthroscopy. 2022 Jul;38(7):2154-2156. doi: 10.1016/j.arthro.2022.02.018.
Stem cell-based therapies are a growing area of interest within regenerative musculoskeletal medicine. Exosomes represent an attractive emergent clinical strategy for the delivery of stem cell-derived growth factors and small molecules to a regenerating tissue environment. Stem cells themselves may not engraft into host tissue but more likely promote a pro-regenerative state through the release of autocrine and paracrine factors. Exosomes, a type of small membrane-bound extracellular vesicle secreted by cells, are of interest as an emergent clinical strategy because they have several key factors that could provide the elusive goal of stem cell therapies in a more practical manner. Exosomes from stem cells appear to have much of the machinery that could promote regenerative capabilities, including growth factors, micro-RNAs (miRNAs), and other signaling molecules that can induce the necessary growth signaling and transcriptional changes to induce a phenotypic change in the local delivery environment. It is important to note that they also have a limited host immune response and can be stored in a freezer, as opposed to many stem cell products that need specialized storage systems to maintain viability. For these reasons, exosome-based therapeutic solutions for rotator cuff repair offer a potential treatment strategy. Recent research provides a highly translational application of exosomes to a chronic rotator cuff repair model and shows efficacy in improving the biomechanical strength of tendon healing at the tendon-bone interface, in addition to partially ameliorating the development of fatty infiltration. Further work is needed to characterize the components of exosomes that result in their bioactivity in addition to considering their cost-effectiveness as a regenerative musculoskeletal treatment.
基于干细胞的疗法是再生肌肉骨骼医学中一个日益受到关注的领域。外泌体是一种有吸引力的新兴临床策略，可将干细胞衍生的生长因子和小分子递送至再生组织环境中。干细胞本身可能不会植入宿主组织，但更有可能通过释放自分泌和旁分泌因子来促进再生状态。外泌体是一种由细胞分泌的小膜结合细胞外囊泡，作为一种新兴的临床策略引起了人们的兴趣，因为它们具有几个关键因素，可以以更实际的方式提供干细胞疗法难以实现的目标。干细胞来源的外泌体似乎具有许多可促进再生能力的机制，包括生长因子、微小 RNA（miRNA）和其他信号分子，这些物质可以诱导必要的生长信号和转录变化，从而在局部递送环境中引起表型变化。值得注意的是，它们的宿主免疫反应也有限，并且可以储存在冰箱中，而许多干细胞产品需要特殊的储存系统来维持其活力。出于这些原因，基于外泌体的肩袖修复治疗方法提供了一种潜在的治疗策略。最近的研究为外泌体在慢性肩袖修复模型中的高度转化应用提供了依据，并显示出在改善肌腱-骨界面处肌腱愈合的生物力学强度方面的疗效，此外还部分改善了脂肪浸润的发展。除了考虑其作为再生肌肉骨骼治疗的成本效益外，还需要进一步研究外泌体的成分，以确定其生物活性的原因。
