Fig. 3: A RA gate supports the proinflammatory state and limits myofibroblast differentiation.

a, Expression scores of signalling pathway genes along the fascia-to-myofibroblast trajectory. b, Expression of chemokine- and RA-related genes. c,d, Representative micrographs of fascia-traced fibroblasts using the Cd201^creERR26^Ai14 system, showing the co-expression with PDPN and CCL2 (c) or CXCL1 (d). e,f, Top, representative immunolabelling for ALDH1A3 (e) and CYP26B1 (f) using ‘16_colours’ pseudo-colouring representing expression intensity. Bottom, magnification of fascia-traced cells showing co-expression with PDPN and ALDH1A3 (e) or CYP26B1 (f). g, Bright-field images of control, RA-treated or CYP26B1 inhibitor (inh)-treated fascia explants (left), explant area over time (top right), and total contraction (bottom right). n = 3 biological replicates. Colours of the image outlines indicate treatments in the graphs. h, Representative micrographs from fascia explants immunolabelled for CCL2, PDPN, RUNX2 or αSMA (left) and the percentage of cells expressing the markers (right) in control, RARγ agonist (ago) or pan-RAR antagonist (antago) treatments. Colours of the image outlines indicate treatments in the graph. n = 3 biological replicates. i, High-magnification images of control (top left) and treated (bottom left) 3 dpi wounds immunolabelled for the immune cell marker CD45, and CD45⁺ cell ratio (right). n = 6 control and 3 treated wounds from 3 biological replicates. Colours of the image outlines indicate treatments in the graph. j, Low-magnification images of Masson’s trichrome-stained control (top left) or treated (bottom left) 14 dpi wounds, and quantification of scar area (middle). The dotted line delimits the analysed wound area. Arrowheads indicate the original injury borders. n = 6 control and treated wounds from 3 biological replicates. High-magnification images of control (top) and treated (bottom) wounds immunolabelled for αSMA and positive cell ratio in scars (right). N = 5 wounds from 3 biological replicates. Colours of the image outlines indicate treatments in the graph. Two-tailed t-tests. Scale bars: 2 mm (g), 500 μm (e,f, top and j, left) and 50 μm (c,d,h,i, and e,f, bottom and j, right).