Fig. 8. Activin affects the biomechanical properties of skin wounds.

a Representative photographs of wounds from WT and Act mice at different days post-injury; scale bar: 2 mm. b Quantification of visible wound and scar lengths (see Supplementary Fig. 8b, d). n = 24, 10, 12, 14, 16, 12 for WT and n = 22, 6, 10, 8, 12, 8 for Act mice in 3-, 5-, 7-, 10-, 14-, or 21-day wounds, respectively. c Rates of wound length change; green dashed line: no change. Left: Rates using averaged values of pooled wounds. Right: Rates using individual wounds, which were tracked across multiple consecutive time points; n = 10 for WT and n = 6 for Act mice for all time points. d Quantification of wound functional length (see Supplementary Fig. 8e); green dashed line indicates the 5 mm diameter of the biopsy punch. For n numbers, see b. e Graph of the ratios of average functional length to corresponding average wound length; green dashed line indicates equal length of functional and visible wounds. f Color maps demonstrating in vivo deformability of wounded tissues (see Supplementary Fig. 8f); scale bar: 2 mm. g Quantification of in vivo wound strain; green dashed line indicates the behavior of unwounded skin. For n numbers, see b. h Ratio of average deformation of wounds from WT to Act mice. i Rates of localized wound deformation change using averaged values of pooled wounds; green dashed line: no change. j Local scar deformability at day 21 post-injury based on ex vivo tensile tests on uniaxial tissue specimens; 10% deformation of the unwounded skin region (green dashed line) is shown for comparison. n = 9 for WT and n = 6 for Act mice. k Tensile strength of WT NS (green line ±SEM) and 21-day scars of WT and Act mice. n = 8 for WT NS (from ref. ¹⁷), n = 10 for WT and n = 6 for Act mice. Graphs show mean ± SEM and P values, with comparisons to NS indicated by #; two-way ANOVA and Bonferroni’s multiple comparison post hoc tests (b, c right, d, g), results of two-way ANOVAs are shown below each graph (first factor: time point, second factor: activin overexpression), cf. Supplementary Table 1 for statistical comparisons across time points; two-tailed Student's t-test (j); one-sample t-test vs NS value (10%) (g, j); one-way ANOVA and Tukey’s multiple comparison post hoc tests (k). All n numbers indicate biological replicates. Source data are provided as a Source Data file (Fig. 8).