title: Capsular polysaccharide from Actinobacillus actinomycetemcomitans inhibits IL-6 and IL-8 production in human gingival fibroblast.
abstract: We previously reported that a capsular polysaccharide (CP) from Actinobacillus actinomycetemcomitans Y4 induces bone resorption in a mouse organ culture system and osteoclast formation in mouse bone marrow cultures. However, the effects of A. actinomycetemcomitans Y4 CP on human gingival fibroblasts (HGF) are still unclear. The present study was undertaken to test the hypothesis that A. actinomycetemcomitans Y4 CP alters the production of inflammatory cytokines, such as interleukin-6 (IL-6) and IL-8 by HGF. When HGF were cultured with various concentrations of Y4 CP for 24 h, IL-6 and IL-8 production decreased in a concentration-dependent manner. Y4 CP (100 microg/ml) suppressed the release of IL-6 from 9.09 +/- 0.08 ng/ml to 0.34 +/- 0.21 ng/ml (P < 0.01) and IL-8 production decreased from 3.76 +/- 0.03 ng/ml to 0.09 +/- 0.01 ng/ml (P < 0.01). Y4 CP suppressed 70-80% of the release of IL-6 and IL-8 from HGF stimulated with Y4 lipopolysaccharide (LPS), too. Interestingly, anti-A. actinomycetemcomitans Y4 CP completely inhibited the effect of A. actinomycetemcomitans Y4 CP on IL-6 and IL-8 production from HGF. These results indicate that Y4 CP inhibits the release of IL-6 and IL-8 from HGF, suggesting that A. actinomycetemcomitans Y4 modulates the inflammatory response in periodontitis. Remarkably, this inhibitory effect was reversed by specific anti-A. actinomycetemcomitans Y4 CP suggesting an important relationship between the organism and the humoral host response.
authors.affiliation: Department of Periodontology, School of Dentistry, Aichi-Gakuin University, Nagoya, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Ohguchi
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Ishihara
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ohguchi
authors.forename: Masanori
authors.initials: M
authors.lastname: Koide
authors.forename: Norimitsu
authors.initials: N
authors.lastname: Shirozu
authors.forename: Takahiro
authors.initials: T
authors.lastname: Naganawa
authors.forename: Tatsuji
authors.initials: T
authors.lastname: Nishihara
authors.forename: Toshihide
authors.initials: T
authors.lastname: Noguchi
mesh_terms: D000328:Adult; D016976:Aggregatibacter actinomycetemcomitans / Q000378:metabolism*; D000704:Analysis of Variance; D000911:Antibodies, Monoclonal / Q000276:immunology; D016667:Bacterial Capsules / Q000494:pharmacology*; D018929:Cell Culture Techniques; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000187:drug effects / Q000276:immunology*; D005881:Gingiva / Q000187:drug effects / Q000276:immunology* / Q000473:pathology; D006801:Humans; D018836:Inflammation Mediators / Q000276:immunology / Q000494:pharmacology; D016209:Interleukin-8 / Q000037:antagonists & inhibitors*; D008070:Lipopolysaccharides / Q000276:immunology / Q000494:pharmacology; D010518:Periodontitis / Q000276:immunology / Q000473:pathology; D011135:Polysaccharides, Bacterial / Q000494:pharmacology*; D013223:Statistics as Topic; D000093242:Interleukin-6 Inhibitors
chemical_list: D000911:Antibodies, Monoclonal; D018836:Inflammation Mediators; D016209:Interleukin-8; D008070:Lipopolysaccharides; D011135:Polysaccharides, Bacterial; D000093242:Interleukin-6 Inhibitors