title: Scar-free cutaneous wound healing in the leopard gecko, Eublepharis macularius.
abstract: Cutaneous wounds heal with two possible outcomes: scarification or near-perfect integumentary restoration. Whereas scar formation has been intensively investigated, less is known about the tissue-level events characterising wounds that spontaneously heal scar-free, particularly in non-foetal amniotes. Here, a spatiotemporal investigation of scar-free cutaneous wound healing following full-thickness excisional biopsies to the tail and body of leopard geckos (Eublepharis macularius) is provided. All injuries healed without scarring. Cutaneous repair involves the development of a cell-rich aggregate within the wound bed, similar to scarring wounds. Unlike scar formation, scar-free healing involves a more rapid closure of the wound epithelium, and a delay in blood vessel development and collagen deposition within the wound bed. It was found that, while granulation tissue of scarring wounds is hypervascular, scar-free wound healing conspicuously does not involve a period of exuberant blood vessel formation. In addition, during scar-free wound healing the newly formed blood vessels are typically perivascular cell-supported. Immunohistochemistry revealed widespread expression of both the pro-angiogenic factor vascular endothelial growth factor A and the anti-angiogenic factor thrombospondin-1 within the healing wound. It was found that scar-free wound healing is an intrinsic property of leopard gecko integument, and involves a modulation of the cutaneous scar repair program. This proportional revascularisation is an important factor in scar-free wound healing.
authors.affiliation: Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada.
authors.forename: Hanna M
authors.initials: HM
authors.lastname: Peacock
authors.affiliation: Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada.
authors.forename: Emily A B
authors.initials: EA
authors.lastname: Gilbert
authors.affiliation: Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada.
authors.forename: Matthew K
authors.initials: MK
authors.lastname: Vickaryous
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D001707:Biopsy, Needle; D002921:Cicatrix / Q000473:pathology / Q000503:physiopathology*; D004848:Epithelium / Q000098:blood supply / Q000378:metabolism / Q000473:pathology; D007150:Immunohistochemistry; D008116:Lizards / Q000502:physiology; D018919:Neovascularization, Physiologic / Q000502:physiology; D012038:Regeneration / Q000502:physiology; D013623:Tail; D019700:Thrombospondin 1 / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D014945:Wound Healing / Q000502:physiology*; D014947:Wounds and Injuries / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D014841:von Willebrand Factor / Q000378:metabolism
chemical_list: D015415:Biomarkers; D019700:Thrombospondin 1; D042461:Vascular Endothelial Growth Factor A; D014841:von Willebrand Factor
keywords: Eublepharis macularius; PCNA; TSP-1; VEGF; biopsy punch; blood vessels; collagen; histology; perivascular cells; wound epithelium