title: Pneumococcal peptidoglycan-polysaccharides regulate Toll-like receptor 2 in the mouse middle ear epithelial cells.
abstract: Toll-like receptor 2 (TLR2) plays a key role in the host defense against Gram staining positive (Gram) bacteria and their cell wall envelope components. However, little is known about the expression of TLR2 in the middle ear under otitis media (OM) conditions, and its role in the persistent otitis media with effusion (OME). In this study, we demonstrated that the pneumococcal cell wall component, peptidoglycan-polysaccharides (PGPS), activated the expression of TLR2 in the middle ear epithelial cells through the nuclear factor kappa B (NF-κB)-cytokine signaling pathway while I kappa B alpha mutant (IκBαM), a dominant negative inhibitor of NF-κB, abrogated the expression of TLR2 induced by PGPS. This study suggests that the existence of residual PGPS may maintain a low profile of cytokine production in the middle ear mucosa and thus contribute to the pathogenesis of OME.
authors.affiliation: Department of Otolaryngology, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Komori
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Jesse
authors.initials: J
authors.lastname: Ping
authors.forename: Ling
authors.initials: L
authors.lastname: Feng
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Toyama
authors.forename: Youngki
authors.initials: Y
authors.lastname: Kim
authors.forename: Patricia
authors.initials: P
authors.lastname: Ferrieri
authors.forename: Jizhen
authors.initials: J
authors.lastname: Lin
mesh_terms: D000818:Animals; D002460:Cell Line; D016207:Cytokines / Q000378:metabolism; D004432:Ear, Middle / Q000187:drug effects* / Q000276:immunology; D004847:Epithelial Cells / Q000187:drug effects* / Q000276:immunology; D017930:Genes, Reporter; D006801:Humans; D020672:I-kappa B Proteins / Q000235:genetics / Q000378:metabolism; D018836:Inflammation Mediators / Q000378:metabolism; D051379:Mice; D009154:Mutation; D000072000:NF-KappaB Inhibitor alpha; D010034:Otitis Media with Effusion / Q000235:genetics / Q000276:immunology* / Q000382:microbiology; D010457:Peptidoglycan / Q000302:isolation & purification / Q000494:pharmacology*; D051381:Rats; D015398:Signal Transduction / Q000187:drug effects; D013296:Streptococcus pneumoniae / Q000276:immunology*; D051195:Toll-Like Receptor 2 / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D051996:Transcription Factor RelA / Q000235:genetics / Q000378:metabolism; D014162:Transfection
chemical_list: D016207:Cytokines; D020672:I-kappa B Proteins; D018836:Inflammation Mediators; C000606204:NFKBIA protein, human; C000606205:Nfkbia protein, mouse; C000606206:Nfkbia protein, rat; D010457:Peptidoglycan; C493486:Tlr2 protein, mouse; D051195:Toll-Like Receptor 2; D051996:Transcription Factor RelA; D000072000:NF-KappaB Inhibitor alpha