Porphyromonas gingivalisandTreponema denticolaMixed Microbial Infection in a Rat Model of Periodontal Disease

[摘要] Porphyromonas gingivalisandTreponema denticolaare periodontal pathogens that express virulence factors associated with the pathogenesis of periodontitis. In this paper we tested the hypothesis thatP. gingivalisandT. denticolaare synergistic in terms of virulence; using a model of mixed microbial infection in rats. Groups of rats were orally infected with eitherP. gingivalisorT. denticolaor mixed microbial infections for 7 and 12 weeks.P. gingivalisgenomic DNA was detected more frequently by PCR thanT. denticola. Both bacteria induced significantly high IgG, IgG2b, IgG1, IgG2a antibody levels indicating a stimulation of Th1 and Th2 immune response. Radiographic and morphometric measurements demonstrated that rats infected with the mixed infection exhibited significantly more alveolar bone loss than shaminfected control rats. Histology revealed apical migration of junctional epithelium, rete ridge elongation, and crestal alveolar bone resorption; resembling periodontal disease lesion. These results showed thatP. gingivalisandT. denticolaexhibit no synergistic virulence in a rat model of periodontal disease.

[学科分类] 传染病学