title: Laminin expression by human periodontal ligament fibroblasts.
abstract: Our previous study demonstrated that a laminin-like molecule produced by periodontal ligament fibroblasts (PLFs) induces gingival epithelial cell chemotaxis. The aim of this study was to identify the laminin isoforms that are expressed by PLFs. Proteins in PLF-conditioned medium from serum-free cultures were separated by gel filtration followed by gelatin-affinity chromatography to remove fibronectin. Protein expression of laminin isoforms was determined using Western blotting, and mRNA expression was examined by RT-PCR. Partially purified laminin evoked gingival epithelial cell chemotaxis, and this activity was blocked by anti-integrin alpha3, alpha6, and beta1 antibodies. Although RT-PCR analysis showed PLFs expressed laminin alpha1 to alpha5, beta1 to beta3, gamma1, and gamma2 chain mRNAs, the predominant laminin chains detected by Western blotting were alpha4, alpha2, beta1, beta2, and gamma1. These results suggest that PLFs secrete mainly laminin-8/9 (alpha4beta1gamma1/alpha4beta2gamma1) and laminin-2/4 (alpha2beta1gamma1/alpha2beta2gamma1). PLF-derived laminins may be involved in the pathogenesis and progression of periodontitis by inducing apical migration of epithelial cells in certain circumstances.
authors.affiliation: Department of Biochemistry, and Division of Functional Morphology, Dental Research Center, Nihon University School of Dentistry, Tokyo, Japan. oshimam@dent.nihon-u.ac.jp
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Ohshima
authors.forename: Yoko
authors.initials: Y
authors.lastname: Yamaguchi
authors.forename: Kichibee
authors.initials: K
authors.lastname: Otsuka
authors.forename: Masashi
authors.initials: M
authors.lastname: Sato
authors.forename: Masako
authors.initials: M
authors.lastname: Ishikawa
mesh_terms: D019138:Antibodies, Blocking / Q000494:pharmacology; D015153:Blotting, Western; D002478:Cells, Cultured; D002630:Chemotactic Factors / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D002633:Chemotaxis / Q000187:drug effects; D017077:Culture Media, Conditioned / Q000737:chemistry; D016895:Culture Media, Serum-Free; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D015870:Gene Expression; D005881:Gingiva / Q000166:cytology / Q000187:drug effects; D006801:Humans; D007797:Laminin / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D010513:Periodontal Ligament / Q000166:cytology / Q000378:metabolism*; D020033:Protein Isoforms; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D019138:Antibodies, Blocking; D002630:Chemotactic Factors; D017077:Culture Media, Conditioned; D016895:Culture Media, Serum-Free; D007797:Laminin; D020033:Protein Isoforms; D012333:RNA, Messenger