Park Dongsu, Spencer Joel A, Lin Charles P, Scadden David T
Center for Regenerative Medicine, Massachusetts General Hospital, Harvard Stem Cell Institute;
Wellman Center for Photomedicine and Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School.
J Vis Exp. 2014 May 23(87):51289. doi: 10.3791/51289.
Bone turns over continuously and is highly regenerative following injury. Osteogenic stem/progenitor cells have long been hypothesized to exist, but in vivo demonstration of such cells has only recently been attained. Here, in vivo imaging techniques to investigate the role of endogenous osteogenic stem/progenitor cells (OSPCs) and their progeny in bone repair are provided. Using osteo-lineage cell tracing models and intravital imaging of induced microfractures in calvarial bone, OSPCs can be directly observed during the first few days after injury, in which critical events in the early repair process occur. Injury sites can be sequentially imaged revealing that OSPCs relocate to the injury, increase in number and differentiate into bone forming osteoblasts. These methods offer a means of investigating the role of stem cell-intrinsic and extrinsic molecular regulators for bone regeneration and repair.
骨骼持续进行更新，受伤后具有高度再生能力。长期以来人们一直推测成骨干细胞/祖细胞的存在，但直到最近才在体内证实了这类细胞的存在。本文提供了用于研究内源性成骨干细胞/祖细胞（OSPCs）及其子代在骨修复中作用的体内成像技术。利用骨系细胞追踪模型和颅骨诱导微骨折的活体成像，可以在损伤后的头几天直接观察到OSPCs，早期修复过程中的关键事件就在这期间发生。可以对损伤部位进行连续成像，结果显示OSPCs迁移至损伤部位，数量增加并分化为形成骨的成骨细胞。这些方法为研究干细胞内在和外在分子调节因子在骨再生和修复中的作用提供了一种手段。
