Fig. 8: Fibroblast-specific Prrx1 expression is critical in the expansion and maintenance of myofibroblast subpopulations during wound healing.

A Illustration of the mouse model in which fibroblast-specific Prrx1 depletion. B Representative images of wound area from day 0 to day 18 post-operative wound in the fibroblast-specific Prrx1-knockout (sgPrrx1, n = 6) and control (sgNS, n = 9) mice, respectively. Delayed wound healing (%) and reduced wound contraction (%) due to Prrx1 deficiency on day 10 post-wound were shown by bar plot (bottom right). Data are presented as the mean ± SEM; n = 5 measurements (two tailed t test, *p < 0.0005, **p < 0.0001). C Decreased myofibroblastic subpopulations during the wound-healing process due to a deficiency of Prrx1. H&E and immunohistochemical stainings of wound area on day 10 post-wound demonstrated the reduced epithelial and dermal layers due to Prrx1 deficiency (bottom left). Box plots showed the number of total fibroblast and fibroblasts expressing α-SMA, PDGFR α, and PCNA between WT and Prrx1 KO mice (bottom right). (n = 3, two tailed t test: *p < 0.005, **p < 0.0005, ***p < 0.0001). D, E Induction of Dox-mediated fibroblast-specific Prrx1 expression in mice 5 days after skin punching. Representative images of wound area from day 0 to day 15 after wounding in fibroblast-specific Prrx1-induced (+Dox, n = 12) and control (−Dox, n = 11) mice were shown. Bar plots indicated an increased wound-healing rate (%) and wound contraction (%) due to Prrx1 overexpression on day 10 post-wound. Data are presented as the mean ± SEM; n = 5 measurements (two tailed t test: *p < 0.0001). F H&E and immunohistochemical images of representative wound area on day 30 post-wound were visualized using ImageJ Fiji (DAPI [hematoxylin]-blue, aSMA-green, TNC-red, PDGFRa-yellow, Prrx1-magenta, PCNA-cyan) (−Dox, n = 11 mice, +Dox, n = 12 mice). The thickness of both epithelial and dermal layers was increased in fibroblast-specific Prrx1 overexpressing mice (bottom left). Box plots showed the number of total fibroblast and fibroblasts expressing α-SMA, PDGFR-α, and PCNA in the wounded tissue (bottom right) (n = 3 measurements, two tailed t test: *p < 0.005, **p < 0.0005, ***p < 0.0001). Source data and exact p values are provided as a Source Data file.