Orthopaedic Soft Tissue Research Program, Hospital for Special Surgery, New York, New York.
J Orthop Res. 2020 Aug;38(8):1666-1675. doi: 10.1002/jor.24667. Epub 2020 Mar 30.
The role of the macrophage is an area of emerging interest in tendinopathy and tendon healing. The macrophage has been found to play a key role in regulating the healing process of the healing tendon. The specific function of the macrophage depends on its functional phenotype. While the M1 macrophage phenotype exhibits a phagocytic and proinflammatory function, the M2 macrophage phenotype is associated with the resolution of inflammation and tissue deposition. Several studies have been conducted on animal models looking at enhancing or suppressing macrophage function, targeting specific phenotypes. These studies include the use of exogenous biological and pharmacological substances and more recently the use of transgenic and genetically modified animals. The outcomes of these studies have been promising. In particular, enhancement of M2 macrophage activity in the healing tendon of animal models have shown decreased scar formation, accelerated healing, decreased inflammation and even enhanced biomechanical strength. Currently our understanding of the role of the macrophage in tendinopathy and tendon healing is limited. Furthermore, the roles of therapies targeting macrophages to enhance tendon healing is unclear. Clinical Significance: An increased understanding of the significance of the macrophage and its functional phenotypes in the healing tendon may be the key to enhancing tendon healing. This review will present the current literature on the function of macrophages in tendinopathy and tendon healing and the potential of therapies targeting macrophages to enhance tendon healing.
巨噬细胞的作用是肌腱病和肌腱愈合研究中一个新兴的关注点。研究发现，巨噬细胞在调节愈合肌腱的愈合过程中起着关键作用。巨噬细胞的特定功能取决于其功能表型。虽然 M1 巨噬细胞表型表现出吞噬和促炎功能，但 M2 巨噬细胞表型与炎症的解决和组织沉积有关。已经在动物模型上进行了几项研究，旨在增强或抑制巨噬细胞功能，针对特定表型。这些研究包括使用外源性生物和药理学物质，以及最近使用转基因和基因修饰动物。这些研究的结果是有希望的。特别是在动物模型的愈合肌腱中增强 M2 巨噬细胞活性，已显示出减少疤痕形成、加速愈合、减少炎症甚至增强生物力学强度。目前，我们对巨噬细胞在肌腱病和肌腱愈合中的作用的理解是有限的。此外，针对巨噬细胞的治疗方法以增强肌腱愈合的作用尚不清楚。临床意义：增加对巨噬细胞及其在愈合肌腱中的功能表型的重要性的理解可能是增强肌腱愈合的关键。这篇综述将介绍目前关于巨噬细胞在肌腱病和肌腱愈合中的功能的文献，以及针对巨噬细胞的治疗方法增强肌腱愈合的潜力。
