title: Cellular events concurrent with Porphyromonas gingivalis invasion of oral epithelium in vitro.
abstract: The aim of the present study was to elucidate events related to receptor function, signal transmission and cytoskeletal rearrangements concurrent with Porphyromonas gingivalis invasion of oral epithelial cells in vitro. Porphyromonas gingivalis strain FDC 381 and the KB cell line (ATCC CCL 17) were used in a previously described antibiotic protection assay. The involvement of a receptor-mediated endocytosis pathway in the internalization process was demonstrated after treatment of the epithelial cells with monodansylcadaverine and ouabain, substances that inhibit formation of coated pits, resulting in reduction in the number of invading P. gingivalis: Treatment of the epithelial cells with the protein kinase (PK) inhibitor staurosporine and the tyrosine-specific PK inhibitor genistein was also found to significantly decrease the number of invading bacteria, suggesting involvement of tyrosine phosphorylation in signal transduction during invasion. This was further supported by the identification of a 43 kD protein acting as a substrate for tyrosine phosphorylation subsequent to the microbial-host cell interaction. Tyrosine phosphorylation of the 43 kD protein was strongly reduced by treatment with PK inhibitors. The decrease in invasion observed after treatment of epithelial cells with colchicine and nocodazole, inhibitors of microtubuli polymerization, suggested that the bacterial-receptor interaction and the phosphotyrosine-dependent intracellular signalling trigger an internalization process involving rearrangements of cytoskeletal microtubuli.
authors.affiliation: Department of Oral Microbiology, Faculty of Odontology, Göteborg University, Sweden. sandros@odontologi.gu.se
authors.forename: J
authors.initials: J
authors.lastname: Sandros
authors.forename: P N
authors.initials: PN
authors.lastname: Madianos
authors.forename: P N
authors.initials: PN
authors.lastname: Papapanou
mesh_terms: D002103:Cadaverine / Q000031:analogs & derivatives / Q000494:pharmacology; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000187:drug effects / Q000378:metabolism; D002478:Cells, Cultured; D003034:Coated Pits, Cell-Membrane / Q000187:drug effects; D003078:Colchicine / Q000494:pharmacology; D003599:Cytoskeleton / Q000648:ultrastructure; D004705:Endocytosis / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004847:Epithelial Cells; D004848:Epithelium / Q000187:drug effects / Q000382:microbiology; D019833:Genistein; D006801:Humans; D007529:Isoflavones / Q000494:pharmacology; D007624:KB Cells; D008870:Microtubules / Q000187:drug effects; D009305:Nasopharynx / Q000166:cytology / Q000187:drug effects / Q000382:microbiology*; D015739:Nocodazole / Q000494:pharmacology; D010042:Ouabain / Q000494:pharmacology; D010766:Phosphorylation / Q000187:drug effects; D016966:Porphyromonas gingivalis / Q000166:cytology* / Q000502:physiology; D047428:Protein Kinase Inhibitors; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D011956:Receptors, Cell Surface / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D019311:Staurosporine / Q000494:pharmacology; D014443:Tyrosine / Q000187:drug effects / Q000378:metabolism
chemical_list: D004791:Enzyme Inhibitors; D007529:Isoflavones; D047428:Protein Kinase Inhibitors; D011956:Receptors, Cell Surface; D014443:Tyrosine; D010042:Ouabain; D019833:Genistein; D011505:Protein-Tyrosine Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D019311:Staurosporine; C008542:monodansylcadaverine; D002103:Cadaverine; D015739:Nocodazole; D003078:Colchicine