title: Hoxb13 knockout adult skin exhibits high levels of hyaluronan and enhanced wound healing.
abstract: In contrast to adult cutaneous wound repair, early gestational fetal cutaneous wounds heal by a process of regeneration, resulting in little or no scarring. Previous studies indicate that down-regulation of HoxB13, a member of the highly conserved family of Hox transcription factors, occurs during fetal scarless wound healing. No down-regulation was noted in adult wounds. Here, we evaluate healing of adult cutaneous wounds in Hoxb13 knockout (KO) mice, hypothesizing that loss of Hoxb13 in adult skin should result in enhanced wound healing. Tensiometry was used to measure the tensile strength of incisional wounds over a 60-day time course; overall, Hoxb13 KO wounds are significantly stronger than wild-type (WT). Histological evaluation of incisional wounds shows that 7-day-old Hoxb13 KO wounds are significantly smaller and that 60-day-old Hoxb13 KO wounds exhibit a more normal collagen architecture compared with WT wounds. We also find that excisional wounds close at a faster rate in Hoxb13 KO mice. Biochemical and histochemical analyses show that Hoxb13 KO skin contains significantly elevated levels of hyaluronan. Because higher levels of hyaluronan and enhanced wound healing are characteristics of fetal skin, we conclude that loss of Hoxb13 produces a more "fetal-like" state in adult skin.
authors.affiliation: Department of Research, Cleveland Clinic Florida, Weston, Florida, USA. mackj@ccf.org
authors.forename: Judith A
authors.initials: JA
authors.lastname: Mack
authors.forename: Susan R
authors.initials: SR
authors.lastname: Abramson
authors.forename: Yixen
authors.initials: Y
authors.lastname: Ben
authors.forename: Jerusha C
authors.initials: JC
authors.lastname: Coffin
authors.forename: James K
authors.initials: JK
authors.lastname: Rothrock
authors.forename: Edward V
authors.initials: EV
authors.lastname: Maytin
authors.forename: Vincent C
authors.initials: VC
authors.lastname: Hascall
authors.forename: Corey
authors.initials: C
authors.lastname: Largman
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Stelnicki
mesh_terms: D000818:Animals; D020405:Dermis / Q000033:anatomy & histology; D018398:Homeodomain Proteins / Q000235:genetics / Q000502:physiology*; D006820:Hyaluronic Acid / Q000096:biosynthesis*; D007700:Kinetics; D051379:Mice; D018345:Mice, Knockout; D012867:Skin / Q000033:anatomy & histology / Q000378:metabolism*; D012879:Skin Physiological Phenomena; D014945:Wound Healing
chemical_list: D018398:Homeodomain Proteins; C100943:Hoxb13 protein, mouse; D006820:Hyaluronic Acid