Analysis of αSMA-labeled progenitor cell commitment identifies notch signaling as an important pathway in fracture healing.

摘要: Fracture healing is a regenerative process that involves coordinated responses of many cell types, but characterization the roles specific populations in this has been limited. We have identified alpha smooth muscle actin (αSMA) as marker population mesenchymal progenitor cells periosteum contributes to osteochondral elements during fracture healing. Using lineage tracing approach, we labeled αSMA-expressing cells, and characterized changes periosteal early stages by histology, flow cytometry, gene expression profiling. In response fracture, αSMA-labeled expanded began differentiate toward osteogenic chondrogenic lineages. The frequency markers such Sca1 PDGFRα increased after fracture. By 6 days genes involved matrix production remodeling were elevated. contrast, associated with contraction Notch signaling downregulated confirmed activating inhibited differentiation into adipogenic lineages vitro ectopic bone formation vivo. characterizing selected callus formation, shown modulation may determine potential