Osteogenic potential of alpha smooth muscle actin expressing muscle resident progenitor cells.

Fiche publication


Date publication

mars 2016

Journal

Bone

Auteurs

Membres identifiés du Cancéropôle Est :
Dr ROEDER Emilie


Tous les auteurs :
Matthews BG, Torreggiani E, Roeder E, Matic I, Grcevic D, Kalajzic I

Résumé

Heterotopic ossification (HO) is a pathological process where bone forms in connective tissues such as skeletal muscle. Previous studies have suggested that muscle-resident non-myogenic mesenchymal progenitors are the likely source of osteoblasts and chondrocytes in HO. However, the previously identified markers of muscle-resident osteoprogenitors label up to half the osteoblasts within heterotopic lesions, suggesting other cell populations are involved. We have identified alpha smooth muscle actin (αSMA) as a marker of osteoprogenitor cells in bone and periodontium, and of osteo-chondro progenitors in the periosteum during fracture healing. We therefore utilized a lineage tracing approach to evaluate whether αSMACreERT2 identifies osteoprogenitors in the muscle. We show that in the muscle, αSMACreERT2 labels both perivascular cells, and satellite cells. αSMACre-labeled cells undergo osteogenic differentiation in vitro and form osteoblasts and chondrocytes in BMP2-induced HO in vivo. In contrast, Pax7CreERT2-labeled muscle satellite cells were restricted to myogenic differentiation in vitro, and rarely contributed to HO in vivo. Our data indicate that αSMACreERT2 labels a large proportion of osteoprogenitors in skeletal muscle, and therefore represents another marker of muscle-resident cells with osteogenic potential under HO-inducing stimulus. In contrast, muscle satellite cells make minimal contribution to bone formation in vivo.

Mots clés

Alpha smooth muscle actin, Heterotopic ossification, Mesenchymal progenitor, Osteogenesis, Satellite cell

Référence

Bone. 2016 03;84:69-77