Fig. 3

Satellite cell activation is transient in CD82^−/− mice and Pax7 expression is retained. a, b Immunofluorescence staining of satellite cells for Pax7 (red) and MyoD (green) 72 h post-extraction from WT (a) and CD82^−/− (b) animals, respectively (n = 6–10/genotype). Arrowhead in (b) points to Pax7⁺MyoD^- cells that are more abundant in CD82^−/− cultures. c Quantification of quiescent Pax7⁺MyoD⁻ satellite cells at 24, 48, and 72 h following isolation and d Pax7⁺MyoD⁺ activated satellite cells from WT and CD82^−/− cultures at the same timepoints (**p ≤ 0.01; ****p ≤ 0.0001). e–h Images and quantification of Pax7⁺Ki67⁻ (g) and Pax7⁺Ki67⁺ (h) cells extracted from WT (e) and CD82^−/− (f) cultures 5 days following isolation (*p < 0.05). Arrowheads in e and f point at Pax7⁺Ki67⁻ cells, which are more abundant in CD82^−/− cultures. i, j Flow cytometry cell cycle profiles of WT and CD82^−/− myogenic cultures following expansion for ~ 30 days. 10,000 events were analyzed per each sample via FACS. k Quantification of percentage of cells in the S-phase and l in the G0/G1 phase from WT and CD82^−/− cultures (*p ≤ 0.05; NS = not significant)