title: Comparison of the virulence of exopolysaccharide-producing Prevotella intermedia to exopolysaccharide non-producing periodontopathic organisms.
abstract: BACKGROUND
  Evidence in the literature suggests that exopolysaccharides (EPS) produced by bacterial cells are essential for the expression of virulence in these organisms. Secreted EPSs form the framework in which microbial biofilms are built.
  
  
  METHODS
  This study evaluates the role of EPS in Prevotella intermedia for the expression of virulence. This evaluation was accomplished by comparing EPS-producing P. intermedia strains 17 and OD1-16 with non-producing P. intermedia ATCC 25611 and Porphyromonas gingivalis strains ATCC 33277, 381 and W83 for their ability to induce abscess formation in mice and evade phagocytosis.
  
  
  RESULTS
  EPS-producing P. intermedia strains 17 and OD1-16 induced highly noticeable abscess lesions in mice at 107 colony-forming units (CFU). In comparison, P. intermedia ATCC 25611 and P. gingivalis ATCC 33277, 381 and W83, which all lacked the ability to produce viscous materials, required 100-fold more bacteria (109 CFU) in order to induce detectable abscess lesions in mice. Regarding antiphagocytic activity, P. intermedia strains 17 and OD1-16 were rarely internalized by human polymorphonuclear leukocytes, but other strains were readily engulfed and detected in the phagosomes of these phagocytes.
  
  
  CONCLUSIONS
  These results demonstrate that the production of EPS by P. intermedia strains 17 and OD1-16 could contribute to the pathogenicity of this organism by conferring their ability to evade the host's innate defence response.
authors.affiliation: Department of Bacteriology, Osaka Dental University, 8-1 Kuzuha-Hanazono, Hirakata, Japan. yamanaka@cc.osaka-dent.ac.jp
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yamanaka
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Yamane
authors.forename: Tomoyo
authors.initials: T
authors.lastname: Furukawa
authors.forename: Chiho
authors.initials: C
authors.lastname: Matsumoto-Mashimo
authors.forename: Chieko
authors.initials: C
authors.lastname: Sugimori
authors.forename: Takayuki
authors.initials: T
authors.lastname: Nambu
authors.forename: Noboru
authors.initials: N
authors.lastname: Obata
authors.forename: Clay B
authors.initials: CB
authors.lastname: Walker
authors.forename: Kai-Poon
authors.initials: KP
authors.lastname: Leung
authors.forename: Hisanori
authors.initials: H
authors.lastname: Fukushima
mesh_terms: D000038:Abscess / Q000382:microbiology / Q000473:pathology; D000818:Animals; D057131:Immune Evasion; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010587:Phagocytosis; D011135:Polysaccharides, Bacterial / Q000378:metabolism*; D016966:Porphyromonas gingivalis / Q000276:immunology / Q000378:metabolism* / Q000472:pathogenicity*; D018713:Prevotella intermedia / Q000276:immunology / Q000378:metabolism* / Q000472:pathogenicity*; D014774:Virulence; D037521:Virulence Factors / Q000378:metabolism*
chemical_list: D011135:Polysaccharides, Bacterial; D037521:Virulence Factors