title: Stimulation of interleukin-8 production in epithelial cell lines by Helicobacter pylori.
abstract: Following exposure to Helicobacter pylori cells, epithelial cell lines secreted interleukin-6 (IL-6) and IL-8 but not tumor necrosis factor alpha. Purified IL-6 alone did not stimulate IL-8 production from the cell lines tested, indicating that IL-6 was not an intermediary in IL-8 induction. Enhanced IL-8 secretion occurred in a time- and dose-dependent manner. None of 12 antibiotics tested exhibited a significant effect on IL-8-inducing activity, suggesting that preformed antigens were responsible for stimulating IL-8 secretion in vitro. Live bacterial cells caused the highest level of stimulation. Proteinase-digested and heated (56 or 100 degrees C) cells had significantly reduced stimulatory activities. Purified H. pylori lipopolysaccharide, but not exopolysaccharide, stimulated low-level secretion of IL-8, but only at high concentrations, while a water-extracted H. pylori antigen preparation was strongly stimulatory for HEp-2 cells. No reduction in IL-8-stimulatory activity was observed for H. pylori mutants negative for urease activity, production of a major lipoprotein, and motility. The noncytotoxic strain CCUG 915 stimulated lower IL-8 levels than other isolates. However, the otherwise isogenic cytotoxin-negative mutant 17874 delta vacA (S. H. Phadnis, D. Ilver, L. Janzon, S. Normark, and T. U. Westblom, Infect. Immun. 62:1557-1565, 1994) had the same IL-8-stimulatory ability as the parent strain, suggesting that surface proteins other than the vacuolating cytotoxin are involved in IL-8 stimulation.
authors.affiliation: Canadian Bacterial Diseases Network, University of Victoria, British Columbia.
authors.forename: J
authors.initials: J
authors.lastname: Huang
authors.forename: P W
authors.initials: PW
authors.lastname: O'Toole
authors.forename: P
authors.initials: P
authors.lastname: Doig
authors.forename: T J
authors.initials: TJ
authors.lastname: Trust
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis; D001427:Bacterial Toxins / Q000032:analysis; D016207:Cytokines / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D003603:Cytotoxins / Q000032:analysis; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells; D004848:Epithelium / Q000187:drug effects / Q000382:microbiology; D016481:Helicobacter Infections / Q000276:immunology*; D016480:Helicobacter pylori / Q000276:immunology*; D006801:Humans; D015151:Immunoblotting; D016209:Interleukin-8 / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D011135:Polysaccharides, Bacterial / Q000494:pharmacology; D012333:RNA, Messenger / Q000032:analysis; D014407:Tumor Cells, Cultured
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D016207:Cytokines; D003603:Cytotoxins; D016209:Interleukin-8; D011135:Polysaccharides, Bacterial; D012333:RNA, Messenger; C074689:VacA protein, Helicobacter pylori