title: Cytokine and chemokine induction using cell wall component and toxin derived from gram-positive bacteria in the rat middle ear.
abstract: Lipoteichoic acid (LTA) is one of the components present within the cell wall layer of most gram-positive bacteria. It plays an important role in the initiation and progression of bacterial infection. In this study, we performed a rat middle ear and nasal perfusion with LTA purified from two different gram-positive bacterial species. Using ELISA and RT-PCR, the production and mRNA expression of rat chemokine, GRO/CINC-1, proinflammatory cytokine, TNF-alpha, in rat middle ear lavage and mucosa were investigated. GRO/CINC-1 in middle ear lavage was produced by stimulation of LTA in a time-dependent fashion; however, TNF-alpha production into the lavage was not detectable using ELISA assay. The mRNA expressions of GRO/CINC-1 and TNF-alpha in the middle ear mucosa were both induced after LTA and exotoxin exposures. The expression of IL-10 mRNA was also induced after 6 h of LTA and exotoxin exposures. The profile of the production of GRO/CINC-1 and TNF-alpha in rat nasal lavage was similar to that in the middle ear; however, the mRNA expressions of GRO/CINC-1, TNF-alpha and IL-10 in the nasal mucosa were different from those in the middle ear mucosa. These results suggest that the cell wall component and exotoxin of gram-positive bacteria can induce several cytokines in vivo and play an important role in the initiation of the inflammatory cascade in the middle ear.
authors.affiliation: Department of Otolaryngology, Sapporo Medical University, School of Medicine, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kita
authors.forename: T
authors.initials: T
authors.lastname: Himi
mesh_terms: D000818:Animals; D054360:Chemokine CXCL1; D019743:Chemokines, CXC / Q000096:biosynthesis*; D002630:Chemotactic Factors / Q000096:biosynthesis*; D004797:Enzyme-Linked Immunosorbent Assay; D006131:Growth Inhibitors / Q000378:metabolism*; D006133:Growth Substances / Q000096:biosynthesis*; D036341:Intercellular Signaling Peptides and Proteins; D016753:Interleukin-10 / Q000096:biosynthesis; D008070:Lipopolysaccharides / Q000633:toxicity*; D008297:Male; D009297:Nasal Mucosa / Q000378:metabolism; D010033:Otitis Media / Q000209:etiology* / Q000276:immunology; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013211:Staphylococcus aureus / Q000378:metabolism; D013297:Streptococcus pyogenes / Q000378:metabolism; D013682:Teichoic Acids / Q000633:toxicity*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
chemical_list: D054360:Chemokine CXCL1; D019743:Chemokines, CXC; D002630:Chemotactic Factors; C513297:Cxcl1 protein, rat; D006131:Growth Inhibitors; D006133:Growth Substances; D036341:Intercellular Signaling Peptides and Proteins; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D013682:Teichoic Acids; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; C009900:lipoteichoic acid