title: Identification of Porphyromonas gingivalis lipopolysaccharide-binding proteins in human saliva.
abstract: Porphyromonas gingivalis causes periodontal diseases and its lipopolysaccharide (LPS) is considered as a major virulence factor responsible for pathogenesis. Since initial recognition of P. gingivalis LPS (Pg.LPS) in the oral cavity might be crucial for the host response, we identified Pg.LPS-binding proteins (Pg.LPS-BPs) using Pg.LPS-immobilized beads and a high-resolution mass spectrometry. LPS purified from P. gingivalis was conjugated onto N-hydroxysuccinimidyl-Sepharose(®) 4 Fast Flow beads. Notably, Pg.LPS-conjugated beads could stimulate Toll-like receptor 2 (TLR2) as determined by a TLR2-depdendent reporter expression system using CHO/CD14/TLR2. In addition, the Pg.LPS-conjugated beads induced the production of inflammatory mediators such as nitric oxide and interferon-gamma-inducible protein-10 in the macrophage cell-line, RAW 264.7. These results imply that Pg.LPS retained its immunological properties during the conjugation process. Then, the Pg.LPS-conjugated beads were mixed with a pool of saliva obtained from nine human subjects to capture Pg.LPS-BPs and molecular identities were determined by LTQ-Orbitrap hybrid fourier transform mass spectrometry. Pg.LPS-BPs captured at high frequencies included alpha-amylase, cystatin, prolactin-inducible protein, lysozyme C, immunoglobulin components, serum albumin, lipocalin-1, and submaxillary gland androgen-regulated protein 3B. These proteins are known to be involved in bacterial adhesion and colonization, anti-microbial functions or modulation of immune responses.
authors: Department of Oral Microbiology and Immunology, Dental Research Institute, and BK21 Program, School of Dentistry, Seoul National University, Seoul 110-749, Republic of Korea.
authors: Seulggie
authors: S
authors: Choi
authors: Jung Eun
authors: JE
authors: Baik
authors: Jun Ho
authors: JH
authors: Jeon
authors: Kun
authors: K
authors: Cho
authors: Deog-Gyu
authors: DG
authors: Seo
authors: Kee-Yeon
authors: KY
authors: Kum
authors: Cheol-Heui
authors: CH
authors: Yun
authors: Seung Hyun
authors: SH
authors: Han
mesh_terms: D000209:Acute-Phase Proteins / Q000276:immunology* / Q000378:metabolism; D000818:Animals; D002352:Carrier Proteins / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D008070:Lipopolysaccharides / Q000276:immunology* / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000276:immunology* / Q000378:metabolism; D051379:Mice; D016966:Porphyromonas gingivalis / Q000276:immunology*; D012463:Saliva / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D012471:Salivary Proteins and Peptides / Q000276:immunology* / Q000378:metabolism; D017550:Spectroscopy, Fourier Transform Infrared; D000099231:Lipopolysaccharide-Binding Protein
chemical_list: D000209:Acute-Phase Proteins; D002352:Carrier Proteins; D008070:Lipopolysaccharides; D008562:Membrane Glycoproteins; D012471:Salivary Proteins and Peptides; D000099231:Lipopolysaccharide-Binding Protein