Fig. 1. Depletion of CD206⁺ M2-like MΦ promotes muscle regeneration.

a Hematoxylin and eosin (H&E)-stained TA tissue paraffin sections of muscle obtained from male C57BL/6J mice following acute injury by cardiotoxin (CTX)-administration. Muscles were harvested at 0, 4, 7, and 14 dpi. n = 2 (D14), and 4 (D0, 4, 7). Scale bar, 200 μm. Asterisks (*) denote necrotic area. b Representative flow cytometry analysis of M2-like MΦ (CD45⁺CD11b⁺F4/80⁺CD206⁺) at 4, 7, and 14 dpi (n = 4 mice per group). c Quantification of CD206⁺ M2-like MΦ (n = 4 mice per group). d Representative flow cytometry analysis of M2-like MΦ (CD45⁺CD11b⁺F4/80⁺CD206⁺) and quantification (e) in muscle of WT and Tg mice harvested at 7 dpi (n = 3 mice per group). f Relative mRNA expression of Mrc1 (CD206) gene in muscle of Tg mice, compared with their littermate WT controls, harvested at 7 dpi (n = 3 mice per group). g Histological sections of Gc muscle from Tg mice and WT control mice, harvested at 7 dpi, stained with H&E (n = 3 mice per group) or WGA and DAPI (n = 4 mice per group). Scale bar, 200 μm (H&E) and 75 μm (WGA). h, i Images stained with DAPI and WGA were used to determine the cross-sectional areas (CSA) (in μm²) of centrally nucleated (CN) fibers (h) and % of CN fibers (i) of the Gc muscle of Tg and WT mice (n = 4 mice per group). j Relative mRNA expression of myogenesis-related marker genes in muscle of Tg mice, compared with their littermate WT control mice. n = 4 (WT), and 5 (Tg) mice. Source data are provided as a Source Data file. The data are shown as the means ± SEM. *p < 0.05, and **p < 0.01 were considered significant as determined using the one-way ANOVA followed by Tukey’s post hoc tests (c), and two-tailed Student t-tests (e–j). WT wild-type, Tg transgenic, mRNA messenger RNA, AU arbitrary units, % percentage, WGA wheat germ agglutinin, and D day.