Fibro-adipogenic progenitors prevent skeletal muscle degeneration at acute phase upon tendon rupture in a murine tibialis anterior tenotomy model

Figure 1 Change in fibro-adipogenic progenitors population after tendon rupture observed in fibro-adipogenic progenitor-tracing mice. A-H: Images of frozen sections of tibialis anterior muscle at 0 day, 3 days, 1 week, 2 weeks, 3 weeks, 4 weeks, 5 weeks, and 6 weeks after tibialis anterior tenotomy in Pdgfra-H2B::eGFP mice, respectively; I: The statistical analysis of the number of EGFP⁺ cells per field counted under microscopy. ^aP < 0.001, 3 days compare to 0 day; ^bP < 0.001, 1 week compare to 0 day; ^cP < 0.001, 2 weeks compare to 0 day; ^dP < 0.01, 3 weeks compare to 0 day; ^eP < 0.01, 4 weeks compare to 0 day; ^fP < 0.01, 5 weeks compare to 0 day; ^gP > 0.05, 6 weeks compare to 0 day. Pdgfra⁺ cells were labeled with enhanced green fluorescence protein. Yellow arrowheads indicate EGFP⁺ cells (i.e., fibro-adipogenic progenitors). Scale bar = 50 μm. TAT: Tibialis anterior tenotomy; FAPs: Fibro-adipogenic progenitors.