Spontaneous myogenic differentiation of Flk-1-positive cells from adult pancreas and other nonmuscle tissues.
At the embryonic or fetal stages, autonomously myogenic cells (AMCs), i.e., cells able to spontaneously differentiate into skeletal myotubes, have been identified from several different sites other than skeletal muscle, including the vascular compartment. However, in the adult animal, AMCs from skeletal muscle-devoid tissues have been described in only two cases. One is represented by thymic myoid cells, a restricted population of committed myogenic progenitors of unknown derivation present in the thymic medulla; the other is represented by a small subset of adipose tissue-associated cells, which we recently identified. In the present study we report, for the first time, the presence of spontaneously differentiating myogenic precursors in the pancreas and in other skeletal muscle-devoid organs such as spleen and stomach, as well as in the periaortic tissue of adult mice. Immunomagnetic selection procedures indicate that AMCs derive from Flk-1(+) progenitors. Individual clones of myogenic cells from nonmuscle organs are morphologically and functionally indistinguishable from skeletal muscle-derived primary myoblasts. Moreover, they can be induced to proliferate in vitro and are able to participate in muscle regeneration in vivo. Thus, we provide evidence that fully competent myogenic progenitors can be derived from the Flk-1(+) compartment of several adult tissues that are embryologically unrelated to skeletal muscle.
Di Rocco
Giuliana
G
Laboratorio di Biologia Vascolare e Terapia Genica, Centro Cardiologico Fondazione Monzino, CCFM, Via Parea 4, 20138 Milano, Italy. g.dirocco@idi.it
Tritarelli
Alessandra
A
Toietta
Gabriele
G
Gatto
Ilaria
I
Iachininoto
Maria Grazia
MG
Pagani
Francesca
F
Mangoni
Antonella
A
Straino
Stefania
S
Capogrossi
Maurizio C
MC
D000818:Animals; D002454:Cell Differentiation / Q000502:physiology*; D002460:Cell Line / Q000502:physiology; D002478:Cells, Cultured; D002999:Clone Cells / Q000166:cytology / Q000378:metabolism; D005753:Gastric Mucosa / Q000378:metabolism; D018189:Immunomagnetic Separation; D051379:Mice; D018485:Muscle Fibers, Skeletal / Q000166:cytology / Q000378:metabolism; D018482:Muscle, Skeletal / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D032446:Myoblasts / Q000166:cytology / Q000378:metabolism*; D010179:Pancreas / Q000166:cytology / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D013154:Spleen / Q000166:cytology / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*; D013270:Stomach / Q000166:cytology; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism*
D042461:Vascular Endothelial Growth Factor A; C467480:vascular endothelial growth factor A, mouse; D040301:Vascular Endothelial Growth Factor Receptor-2