Invasion of Human Oral Epithelial Cells byPrevotella intermedia

ABSTRACT Invasion of oral epithelial cells by pathogenic oral bacteria may represent an important virulence factor in the progression of periodontal disease. Here we report that a clinical isolate ofPrevotella intermedia, strain 17, was found to invade a human oral epithelial cell line (KB), whereas P. intermedia 27, another clinical isolate, and P. intermedia 25611, the type strain, were not found to invade the cell line. Invasion was quantified by the recovery of viable bacteria following a standard antibiotic protection assay and observed by electron microscopy. Cytochalasin D, cycloheximide, monodansylcadaverine, and low temperature (4°C) inhibited the internalization of P. intermedia 17. Antibodies raised against P. intermedia type C fimbriae and against whole cells inhibited invasion, but the anti-type-C-fimbria antibody inhibited invasion to a greater extent than the anti-whole-cell antibody. This work provides evidence that at least one strain ofP. intermedia can invade an oral epithelial cell line and that the type C fimbriae and a cytoskeletal rearrangement are required for this invasion.

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Arginine-Specific Protease fromPorphyromonas gingivalis Activates Protease-Activated Receptors on Human Oral Epithelial Cells and Induces Interleukin-6 Secretion

Infection and Immunity ◽

10.1128/iai.69.8.5121-5130.2001 ◽

2001 ◽

Vol 69 (8) ◽

pp. 5121-5130 ◽

Cited By ~ 168

Author(s):

Afrodite Lourbakos ◽

Jan Potempa ◽

James Travis ◽

Michael R. D'Andrea ◽

Patricia Andrade-Gordon ◽

...

Keyword(s):

Epithelial Cell ◽

Epithelial Cells ◽

Periodontal Disease ◽

Intracellular Calcium ◽

Cell Line ◽

Interleukin 6 ◽

Epithelial Cell Line ◽

Protease Activated Receptors ◽

Oral Epithelial Cells ◽

Oral Epithelial

ABSTRACT Periodontitis is a chronic inflammatory disease affecting oral tissues. Oral epithelial cells represent the primary barrier against bacteria causing the disease. We examined the responses of such cells to an arginine-specific cysteine proteinase (RgpB) produced by a causative agent of periodontal disease, Porphyromonas gingivalis. This protease caused an intracellular calcium transient in an oral epithelial cell line (KB), which was dependent on its enzymatic activity. Since protease-activated receptors (PARs) might mediate such signaling, reverse transcription-PCR was used to characterize the range of these receptors expressed in the KB cells. The cells were found to express PAR-1, PAR-2, and PAR-3, but not PAR-4. In immunohistochemical studies, human gingival epithelial cells were found to express PAR-1, PAR-2, and PAR-3 on their surface, but not PAR-4, indicating that the cell line was an effective model for the in vivo situation. PAR-1 and PAR-2 expression was confirmed in intracellular calcium mobilization assays by treatment of the cells with the relevant receptor agonist peptides. Desensitization experiments strongly indicated that signaling of the effects of RgpB was occurring through PAR-1 and PAR-2. Studies with cells individually transfected with each of these two receptors confirmed that they were both activated by RgpB. Finally, it was shown that, in the oral epithelial cell line, PAR activation by the bacterial protease-stimulated secretion of interleukin-6. This induction of a powerful proinflammatory cytokine suggests a mechanism whereby cysteine proteases from P. gingivalis might mediate inflammatory events associated with periodontal disease on first contact with a primary barrier of cells.

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The Influence of Oral Bacteria on Epithelial Cell MigrationIn Vitro

Mediators of Inflammation ◽

10.1155/2013/154532 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 17

Author(s):

Alexa M. G. A. Laheij ◽

Johannes J. de Soet ◽

Enno C. I. Veerman ◽

Jan G. M. Bolscher ◽

Cor van Loveren

Keyword(s):

Epithelial Cell ◽

Epithelial Cells ◽

Oral Bacteria ◽

Bacterial Cells ◽

Oral Epithelial Cells ◽

Prevotella Nigrescens ◽

Hematopoetic Stem Cell ◽

Oral Epithelial ◽

Hematopoetic Stem Cell Transplantation

Oral ulcerations often arise as a side effect from chemo- and radiation therapy. In a previous clinical study,Porphyromonas gingivaliswas identified as a positive predictor for oral ulcerations after hematopoetic stem cell transplantation, possibly incriminatingP. gingivalisin delayed healing of the ulcerations. Therefore, it was tested whetherP. gingivalisand its secreted products could inhibit the migration of oral epithelial cells in anin vitroscratch assay. To compare, the oral bacteriaPrevotella nigrescens,Prevotella intermedia,Tannerella forsythia, andStreptococcus mitiswere included. A standardized scratch was made in a confluent layer of human oral epithelial cells. The epithelial cells were challenged with bacterial cells and with medium containing secretions of these bacteria. Closure of the scratch was measured after 17 h using a phase contrast microscope.P. gingivalis,P. nigrescens, and secretions ofP. gingivalisstrongly inhibited cell migration. A challenge with 1000 heat-killed bacteria versus 1 epithelial cell resulted in a relative closure of the scratch of 25% forP. gingivalisand 20% forP. nigrescens. Weaker inhibitory effects were found for the other bacteria. The results confirmed our hypothesis that the oral bacteria may be involved in delayed wound healing.

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Characteristics of a cancerous cell line, HIOEC-B(a)P-96, induced by benzo(a)pyrene from human immortalized oral epithelial cell line

Archives of Oral Biology ◽

10.1016/j.archoralbio.2007.12.002 ◽

2008 ◽

Vol 53 (5) ◽

pp. 443-452 ◽

Cited By ~ 34

Author(s):

Lai-Ping Zhong ◽

Hong-Ya Pan ◽

Xiao-Jian Zhou ◽

Dong-Xia Ye ◽

Lei Zhang ◽

...

Keyword(s):

Epithelial Cell ◽

Cell Line ◽

Epithelial Cell Line ◽

Oral Epithelial Cell ◽

Cancerous Cell ◽

Oral Epithelial

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Potential Role for a Carbohydrate Moiety in Anti-Candida Activity of Human Oral Epithelial Cells

Infection and Immunity ◽

10.1128/iai.69.11.7091-7099.2001 ◽

2001 ◽

Vol 69 (11) ◽

pp. 7091-7099 ◽

Cited By ~ 40

Author(s):

Chad Steele ◽

Janet Leigh ◽

Rolf Swoboda ◽

Hatice Ozenci ◽

Paul L. Fidel

Keyword(s):

Epithelial Cell ◽

Epithelial Cells ◽

Oral Mucosa ◽

Host Defense ◽

Defense Mechanisms ◽

Carbohydrate Moiety ◽

Sulfated Polysaccharides ◽

Oral Epithelial Cells ◽

Oral Epithelial Cell ◽

Oral Epithelial

ABSTRACT Candida albicans is both a commensal and a pathogen at the oral mucosa. Although an intricate network of host defense mechanisms are expected for protection against oropharyngeal candidiasis, anti-Candida host defense mechanisms at the oral mucosa are poorly understood. Our laboratory recently showed that primary epithelial cells from human oral mucosa, as well as an oral epithelial cell line, inhibit the growth of blastoconidia and/or hyphal phases of several Candida species in vitro with a requirement for cell contact and with no demonstrable role for soluble factors. In the present study, we show that oral epithelial cell-mediated anti-Candida activity is resistant to gamma-irradiation and is not mediated by phagocytosis, nitric oxide, hydrogen peroxide, and superoxide oxidative inhibitory pathways or by nonoxidative components such as soluble defensin and calprotectin peptides. In contrast, epithelial cell-mediated anti-Candida activity was sensitive to heat, paraformaldehyde fixation, and detergents, but these treatments were accompanied by a significant loss in epithelial cell viability. Treatments that removed existing membrane protein or lipid moieties in the presence or absence of protein synthesis inhibitors had no effect on epithelial cell inhibitory activity. In contrast, the epithelial cell-mediated anti-Candida activity was abrogated after treatment of the epithelial cells with periodic acid, suggesting a role for carbohydrates. Adherence of C. albicans to oral epithelial cells was unaffected, indicating that the carbohydrate moiety is exclusively associated with the growth inhibition activity. Subsequent studies that evaluated specific membrane carbohydrate moieties, however, showed no role for sulfated polysaccharides, sialic acid residues, or glucose- and mannose-containing carbohydrates. These results suggest that oral epithelial cell-mediated anti-Candida activity occurs exclusively with viable epithelial cells through contact with C. albicans by an as-yet-undefined carbohydrate moiety.

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Proteolysis of ICAM-1 on Human Oral Epithelial Cells by Gingipains

Journal of Dental Research ◽

10.1177/154405910308201007 ◽

2003 ◽

Vol 82 (10) ◽

pp. 796-801 ◽

Cited By ~ 41

Author(s):

H. Tada ◽

S. Sugawara ◽

E. Nemoto ◽

T. Imamura ◽

J. Potempa ◽

...

Keyword(s):

Epithelial Cell ◽

Epithelial Cells ◽

Immune Evasion ◽

Intercellular Adhesion Molecule ◽

Dependent Manner ◽

Intercellular Adhesion Molecule 1 ◽

Periodontal Tissues ◽

Oral Epithelial Cells ◽

Oral Epithelial Cell ◽

Oral Epithelial

Cysteine proteinases (gingipains) from Porphyromonas gingivalis are considered key virulence factors of severe periodontitis and host immune evasion. Since expression of intercellular adhesion molecule-1 (ICAM-1) on gingival epithelium is indispensable in polymorphonuclear leukocyte (PMN) migration at the site of periodontitis, we examined the effects of gingipains on the expression of ICAM-1 on human oral epithelial cell lines (KB and HSC-2) by flow cytometry and Western blotting. We found that three purified forms of gingipains efficiently reduced ICAM-1 expression on the cells in a time- and dose-dependent manner. Gingipains reduced the expression on fixed cells and degraded the ICAM-1 in the cell membranes, indicating that the reduction resulted from direct proteolysis. They then disturbed the ICAM-1-dependent adhesion of PMNs to the cells. These results indicate that gingipains cleave ICAM-1 on oral epithelial cells, consequently disrupting PMN-oral epithelial cell interaction, and are involved in immune evasion by the bacterium in periodontal tissues.

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