Keratinocytes in human wounds express alpha v beta 6 integrin.
Cell adhesion receptors of the integrin family play a major role during re-epithelialization of human wounds. We have previously documented that the expression of alpha v family integrins is induced in keratinocytes of mucosal wounds [1]. In the present investigation, we extended these studies to determine whether alpha v beta 6 integrin is expressed during wound healing in humans. Mucosal and epidermal wound sections from 1- to 7-day-old wounds were used for immunolocalization of integrins and their putative ligands. In addition, freshly isolated epidermal keratinocytes were used to study integrin expression in vitro. Expression of alpha v beta 6 integrin appeared relatively late during mucosal and dermal wound healing. Maximal expression was seen in 7-day-old wounds in which epithelial sheets had fused and granulation tissue was present. Fibronectin and tenascin, both possible ligands for alpha v beta 6 integrin, were found concentrated underneath the basal epithelial cells expressing this receptor, and the maximal expression of tenascin coincided with that of alpha v beta 6 integrin. Freshly isolated epidermal keratinocytes did not stain for alpha v beta 6 integrin but began to express this integrin after subculturing. Our results suggest that the expression of alpha v beta 6 integrin, a putative binding integrin for fibronectin and tenascin, is induced in keratinocytes when epithelial sheets fuse during wound healing.
Haapasalmi
K
K
Department of Oral Biology, University of British Columbia, Vancouver, Canada.
Zhang
K
K
Tonnesen
M
M
Olerud
J
J
Sheppard
D
D
Salo
T
T
Kramer
R
R
Clark
R A
RA
Uitto
V J
VJ
Larjava
H
H
D000951:Antigens, Neoplasm; D002469:Cell Separation; D002478:Cells, Cultured; D005353:Fibronectins / Q000378:metabolism; D006801:Humans; D016023:Integrins / Q000502:physiology*; D015603:Keratinocytes / Q000737:chemistry*; D009092:Mucous Membrane / Q000293:injuries / Q000378:metabolism / Q000473:pathology; D012867:Skin / Q000293:injuries* / Q000378:metabolism / Q000473:pathology; D019063:Tenascin / Q000378:metabolism; D014018:Tissue Distribution; D014950:Wounds, Penetrating / Q000473:pathology*
D000951:Antigens, Neoplasm; D005353:Fibronectins; D016023:Integrins; D019063:Tenascin; C073878:integrin alphavbeta6