title: Integrins in periodontal disease.
abstract: Cell surface integrin receptors mediate cell adhesion, migration and cellular signaling in all nucleated cells. They are activated by binding to extracellular ligands or by intracellular proteins, such as kindlins that engage with their cytoplasmic tails. Cells in the periodontal tissues express several integrins with overlapping ligand-binding capabilities. A distinct phenotype in the periodontium has only been described for knockouts or mutations of three integrin subunits, α11, β6 and β2. Integrin α11β1 appears to have some regulatory function in the periodontal ligament of continuously erupting incisors in mice. Integrin αvβ6 is expressed in the junctional epithelium (JE) of the gingiva. Animals deficient in this receptor develop classical signs of periodontal disease, including inflammation, apical migration of the JE and bone loss, suggesting that it plays a role in the regulation of periodontal inflmmation, likely through activation of transforming growth factor-β1. Lack of integrin activation in the JE is also associated with periodontitis. Patients with kindlin-1 mutations have severe early-onset periodontal disease. Finally, patients with mutations in the leukocyte-specific β2 integrin subunit have severe periodontal problems due to lack of transiting neutrophils in the periodontal tissues.
authors.affiliation: Laboratory of Periodontal Biology, Department of Oral Biological and Medical Sciences, Faculty of Dentistry, University of British Columbia, 2199 Wesbrook Mall, Vancouver, BC, Canada V6T 1Z3. Electronic address: larjava@dentistry.ubc.ca.
authors.forename: Hannu
authors.initials: H
authors.lastname: Larjava
authors.affiliation: Laboratory of Periodontal Biology, Department of Oral Biological and Medical Sciences, Faculty of Dentistry, University of British Columbia, 2199 Wesbrook Mall, Vancouver, BC, Canada V6T 1Z3.
authors.forename: Leeni
authors.initials: L
authors.lastname: Koivisto
authors.affiliation: Department of Biochemistry, University of Turku, Turku, Finland.
authors.forename: Jyrki
authors.initials: J
authors.lastname: Heino
authors.affiliation: Laboratory of Periodontal Biology, Department of Oral Biological and Medical Sciences, Faculty of Dentistry, University of British Columbia, 2199 Wesbrook Mall, Vancouver, BC, Canada V6T 1Z3.
authors.forename: Lari
authors.initials: L
authors.lastname: Häkkinen
mesh_terms: D000818:Animals; D006801:Humans; D016023:Integrins / Q000378:metabolism*; D051379:Mice; D010510:Periodontal Diseases / Q000378:metabolism* / Q000473:pathology
chemical_list: D016023:Integrins
keywords: Cell adhesion; Gingiva; Integrins; Junctional epithelium; Periodontal disease; Periodontal ligament