title: Th1 biased response to a novel Porphyromonas gingivalis protein aggravates bone resorption caused by this oral pathogen.
abstract: In previous studies we showed that biasing the immune response to Porphyromonas gingivalis antigens to the Th1 phenotype increases inflammatory bone resorption caused by this organism. Using a T cell screening strategy we identified eight P. gingivalis genes coding for proteins that appear to be involved in T-helper cell responses. In the present study, we characterized the protein encoded by the PG_1841 gene and evaluated its relevance in the bone resorption caused by P. gingivalis because subcutaneous infection of mice with this organism resulted in the induction of Th1 biased response to the recombinant PG1841 antigen molecule. Using an immunization regime that strongly biases toward the Th1 phenotype followed by challenge with P. gingivalis in dental pulp tissue, we demonstrate that mice pre-immunized with rPG1841 developed severe bone loss compared with control immunized mice. Pre-immunization of mice with the antigen using a Th2 biasing regime resulted in no exacerbation of the disease. These results support the notion that selected antigens of P. gingivalis are involved in a biased Th1 host response that leads to the severe bone loss caused by this oral pathogen.
authors.affiliation: Department of Cytokine Biology, The Forsyth Institute, Boston, MA 02115140, USA.
authors.forename: Onir
authors.initials: O
authors.lastname: Leshem
authors.forename: Suely S
authors.initials: SS
authors.lastname: Kashino
authors.forename: Reginaldo B
authors.initials: RB
authors.lastname: Gonçalves
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Suzuki
authors.forename: Masao
authors.initials: M
authors.lastname: Onodera
authors.forename: Akira
authors.initials: A
authors.lastname: Fujimura
authors.forename: Hajime
authors.initials: H
authors.lastname: Sasaki
authors.forename: Philip
authors.initials: P
authors.lastname: Stashenko
authors.forename: Antonio
authors.initials: A
authors.lastname: Campos-Neto
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology; D001426:Bacterial Proteins / Q000633:toxicity*; D001862:Bone Resorption / Q000139:chemically induced* / Q000276:immunology; D016905:Gram-Negative Bacterial Infections / Q000276:immunology* / Q000503:physiopathology; D051379:Mice; D016966:Porphyromonas gingivalis / Q000737:chemistry* / Q000472:pathogenicity; D018417:Th1 Cells / Q000187:drug effects* / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins