Airway epithelial wound repair: role of carbohydrate sialyl Lewisx.
Epithelial repair is a complex cellular and molecular process, the details of which are still not clearly understood. Plasma membrane glycoconjugates can modulate cell function by altering the function of protein and lipids. Sialyl Lewisx (sLex), a fucose-containing tetrasaccharide, decorates membrane-bound and secreted proteins and mediates cell-cell interaction. In the present study we investigated the role of sLex in airway epithelial repair. Using immunohistochemistry, we showed an increased expression of sLex in areas of damaged bronchial epithelium compared with intact regions. Confluent monolayers of airway epithelial cells were mechanically wounded and allowed to close. Wounded monolayers were photographed for wound closure kinetics, fixed for immunocytochemical studies, or subjected to RNA extraction. Examining the expression of different alpha1,3-fucosyltransferases (FucT), enzymes that mediate the final step in the synthesis of sLex, we found that FucT-IV was the common gene expressed in all cell lines and primary airway epithelial cells. We demonstrated an increased expression of sLex over time after mechanical injury. Blocking of sLex with an inhibitory antibody completely prevented epithelial repair. Our data suggest an essential functional role for sLex in epithelial repair. Further studies are necessary to explore the exact mechanism for sLex in mediating cell-cell interaction in bronchial epithelial cells to facilitate epithelial migration and repair.
Allahverdian
Sima
S
The James Hogg iCAPTURE Centre for Cardiovascular and Pulmonary Research, Faculty of Medicine, St. Paul's Hospital, University of British Columbia, Rm. 166, 1081 Burrard St., Vancouver, BC, Canada V6Z 1Y6.
Wojcik
Kimberly R
KR
Dorscheid
Delbert R
DR
D000328:Adult; D000906:Antibodies / Q000494:pharmacology; D001980:Bronchi / Q000293:injuries* / Q000378:metabolism; D050260:Carbohydrate Metabolism; D002241:Carbohydrates / Q000502:physiology*; D002478:Cells, Cultured; D004357:Drug Synergism; D019040:E-Selectin / Q000378:metabolism; D004815:Epidermal Growth Factor / Q000494:pharmacology; D004847:Epithelial Cells / Q000378:metabolism; D004848:Epithelium / Q000293:injuries; D005647:Fucosyltransferases / Q000378:metabolism / Q000494:pharmacology; D006801:Humans; D007983:Lewis Blood Group Antigens; D016256:Lewis X Antigen; D009844:Oligosaccharides / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D000080506:Sialyl Lewis X Antigen; D014945:Wound Healing / Q000187:drug effects / Q000502:physiology*; D014949:Wounds, Nonpenetrating
D000906:Antibodies; D002241:Carbohydrates; D019040:E-Selectin; D007983:Lewis Blood Group Antigens; D016256:Lewis X Antigen; D009844:Oligosaccharides; D000080506:Sialyl Lewis X Antigen; D004815:Epidermal Growth Factor; C066693:FUT4 protein, human; C502597:FUT7 protein, human; D005647:Fucosyltransferases; C019818:3-galactosyl-N-acetylglucosaminide 4-alpha-L-fucosyltransferase