title: Early-gestation fetal scarless wounds have less lysyl oxidase expression.
abstract: BACKGROUND
  Lysyl oxidase cross-links collagen and elastin. Because cross-linking likely influences collagen architecture, the authors compared lysyl oxidase expression during scarless and scarring fetal dermal wound repair.
  
  
  METHODS
  Excisional dermal wounds were made on E17 (gestational day 16.5) and E19 (gestational day 18.5) mouse fetuses. Skin and wound RNA was collected at 8, 12, and 24 hours. Quantitative real-time polymerase chain reaction was performed for lysyl oxidase. The effect of transforming growth factor (TGF)-beta1 on lysyl oxidase expression in fetal fibroblasts was tested. Confluent primary fetal and postnatal fibroblast cultures were stimulated with TGF-beta1 for 24 hours, and lysyl oxidase expression was quantitated by performing real-time polymerase chain reaction. Lysyl oxidase expression was also quantitated in unwounded fetal skin to determine its expression profile during development.
  
  
  RESULTS
  E17 and E19 fetal skin had approximately 2-fold greater lysyl oxidase expression than postnatal skin (p < 0.01), and fetal fibroblasts had greater baseline lysyl oxidase expression than postnatal fibroblasts. After TGF-beta1 stimulation, fetal and postnatal fibroblasts responded with increases in lysyl oxidase expression. In E17 early-gestation scarless fetal wounds, lysyl oxidase had small increases (<1.5-fold) in expression from 1 to 12 hours. In late-gestation E19 scarring fetal wounds, lysyl oxidase increased 1.8-fold at 8 hours and 2-fold at 12 hours, which was significantly greater than the changes observed in E17 scarless wounds (p < 0.01 for each).
  
  
  CONCLUSIONS
  Lysyl oxidase has greater expression in E19 late-gestation wounds that heal with scar compared with E17 early-gestation scarless wounds. This suggests a role for lysyl oxidase in scar formation.
authors.affiliation: Stanford, Calif. From the Department of Surgery, Division of Plastic Surgery, Children's Surgical Research Program, Tissue Regeneration Laboratory.
authors.forename: Amy S
authors.initials: AS
authors.lastname: Colwell
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Krummel
authors.forename: Michael T
authors.initials: MT
authors.lastname: Longaker
authors.forename: H Peter
authors.initials: HP
authors.lastname: Lorenz
mesh_terms: D000818:Animals; D002478:Cells, Cultured / Q000187:drug effects / Q000201:enzymology; D002921:Cicatrix / Q000196:embryology / Q000201:enzymology* / Q000209:etiology; D003094:Collagen / Q000378:metabolism; D004548:Elasticity; D004790:Enzyme Induction / Q000187:drug effects; D005315:Fetal Diseases / Q000201:enzymology*; D005347:Fibroblasts / Q000187:drug effects / Q000201:enzymology*; D005865:Gestational Age; D051379:Mice; D008807:Mice, Inbred BALB C; D008249:Protein-Lysine 6-Oxidase / Q000032:analysis* / Q000096:biosynthesis / Q000502:physiology; D012867:Skin / Q000196:embryology / Q000201:enzymology / Q000254:growth & development / Q000293:injuries*; D016212:Transforming Growth Factor beta / Q000494:pharmacology; D053773:Transforming Growth Factor beta1; D014945:Wound Healing; D014947:Wounds and Injuries / Q000196:embryology / Q000201:enzymology
chemical_list: C508961:Tgfb1 protein, mouse; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D003094:Collagen; D008249:Protein-Lysine 6-Oxidase