ABSTRACT
Skeletal stem cells (SSCs) generate the progenitors needed for growth, maintenance and repair of the skeleton. Historically, SSCs have been defined as bone marrow-derived cells with inconsistent characteristics. However, recent in vivo tracking experiments have revealed the presence of SSCs not only within the bone marrow but also within the periosteum and growth plate reserve zone. These studies show that SSCs are highly heterogeneous with regard to lineage potential. It has also been revealed that, during digit tip regeneration and in some non-mammalian vertebrates, the dedifferentiation of osteoblasts may contribute to skeletal regeneration. Here, we examine how these research findings have furthered our understanding of the diversity and plasticity of SSCs that mediate skeletal maintenance and repair.
Footnotes
Funding
The authors were funded by the National Institutes of Health [T32 HD060549 to M.A.S. R21 DE023899 and R35 DE027550 to J.G.C.; R21 AR064462 and R01 AR069700 to F.V.M.] and a University of Southern California Regenerative Medicine Initiative Award to F.V.M. and J.G.C. Deposited in PMC for release after 12 months.
