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Bacterial internalization in periodontitis.

L Vitkov·W D Krautgartner·M Hannig
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Abstract

BACKGROUND: Bacterial invasion of host epithelial cells plays an important role in the pathogenesis of periodontitis; however, the exact mechanism of the invasion has not been investigated. METHODS: Pocket epithelium biopsies in periodontitis were analysed via scanning and transmission electron microscopy using ultra-histochemical staining with ruthenium red for glycocalyx visualization. RESULTS: We demonstrated that oral bacteria adhered via fimbriae-mediated adhesion only. The bacterial internalization in periodontitis was marked by the hallmark of the fimbriae-induced zipper mechanism--the phagocytic cup formation--but we found no sign of the trigger mechanism of internalization. In addition, we frequently observed apoptosis in the phagocytizing epithelial cells. CONCLUSION: Fimbriae-mediated adhesion is a prerequisite for bacterial invasion in periodontitis. This occurs by the fimbriae-induced zipper mechanism of internalization. As internalization induces apoptosis, the subsequent exfoliation might play a significant role in the clearance of periodontal pathogens.

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ApoptosisBacteriaBacterial AdhesionBacterial Physiological PhenomenaColoring AgentsEpithelial CellsFimbriae, BacterialGingivaGlycocalyxHumansMicroscopy, Electron, ScanningMicroscopy, Electron, TransmissionMiddle AgedPeriodontal PocketPeriodontitisPhagocytosisRuthenium RedJournal Article

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L Vitkov, W D Krautgartner, M Hannig. 2005. Bacterial internalization in periodontitis.. https://doi.org/10.1111/j.1399-302x.2005.00233.x

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