title: Comparison of Moraxella catarrhalis isolates from children and adults for growth on modified New York City medium and potential virulence factors.
abstract: Initial studies found that Moraxella catarrhalis isolates from adults that grew on modified New York City medium (MNYC(+)) that contained antibiotics selective for pathogenic neisseriae differed from strains that did not grow on this medium (MNYC(-)) in their potential virulence properties. It was predicted that higher usage of antibiotics to treat respiratory illness in children might result in higher proportions of MNYC(+) isolates if antibiotics were an important selective pressure for this phenotype. Two of 100 adult isolates (2 %) were MNYC(+), compared to 88 of 88 isolates (100 %) from children (P = 0.000). MNYC(+) strains were serum-resistant and bound in higher numbers to HEp-2 cells that were infected with respiratory syncytial virus (RSV). Endotoxin from an MNYC(+) isolate induced significantly higher pro-inflammatory response levels than endotoxin from an MNYC(-) strain. MNYC(-) adult isolates expressed haemagglutinins and bound in lower numbers to RSV-infected cells, but serum resistance was variable. All isolates from children were MNYC(+), serum-resistant and bound in greater numbers to RSV-infected cells. These results indicate that both RSV infection and antibiotic usage select for the MNYC(+) phenotype.
authors.affiliation: Department of Medical Microbiology, University of Edinburgh, Edinburgh, Scotland, UK 2Institute for Scientific Evaluation of Naturopathy, University of Cologne, Cologne, Germany 3Discipline of Immunology and Microbiology, University of Newcastle, Newcastle, Australia.
authors.forename: Omar R
authors.initials: OR
authors.lastname: El Ahmer
authors.affiliation: Department of Medical Microbiology, University of Edinburgh, Edinburgh, Scotland, UK 2Institute for Scientific Evaluation of Naturopathy, University of Cologne, Cologne, Germany 3Discipline of Immunology and Microbiology, University of Newcastle, Newcastle, Australia.
authors.forename: J Matthias
authors.initials: JM
authors.lastname: Braun
authors.affiliation: Department of Medical Microbiology, University of Edinburgh, Edinburgh, Scotland, UK 2Institute for Scientific Evaluation of Naturopathy, University of Cologne, Cologne, Germany 3Discipline of Immunology and Microbiology, University of Newcastle, Newcastle, Australia.
authors.forename: Sebastian G B
authors.initials: SGB
authors.lastname: Amyes
authors.affiliation: Department of Medical Microbiology, University of Edinburgh, Edinburgh, Scotland, UK 2Institute for Scientific Evaluation of Naturopathy, University of Cologne, Cologne, Germany 3Discipline of Immunology and Microbiology, University of Newcastle, Newcastle, Australia.
authors.forename: Donald M
authors.initials: DM
authors.lastname: Weir
authors.affiliation: Department of Medical Microbiology, University of Edinburgh, Edinburgh, Scotland, UK 2Institute for Scientific Evaluation of Naturopathy, University of Cologne, Cologne, Germany 3Discipline of Immunology and Microbiology, University of Newcastle, Newcastle, Australia.
authors.forename: Josef
authors.initials: J
authors.lastname: Beuth
authors.affiliation: Department of Medical Microbiology, University of Edinburgh, Edinburgh, Scotland, UK 2Institute for Scientific Evaluation of Naturopathy, University of Cologne, Cologne, Germany 3Discipline of Immunology and Microbiology, University of Newcastle, Newcastle, Australia.
authors.forename: C Caroline
authors.initials: CC
authors.lastname: Blackwell
mesh_terms: D000328:Adult; D000367:Age Factors; D000372:Agglutination Tests; D001425:Bacterial Outer Membrane Proteins / Q000276:immunology*; D045744:Cell Line, Tumor; D002648:Child; D003168:Complement Fixation Tests; D003470:Culture Media; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology; D001936:Moraxella catarrhalis / Q000254:growth & development* / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism; D045828:Moraxellaceae Infections / Q000382:microbiology; D009844:Oligosaccharides / Q000276:immunology; D012136:Respiratory Syncytial Viruses / Q000502:physiology; D012141:Respiratory Tract Infections / Q000276:immunology / Q000382:microbiology; D037521:Virulence Factors / Q000378:metabolism
chemical_list: D001425:Bacterial Outer Membrane Proteins; D003470:Culture Media; D008070:Lipopolysaccharides; D009844:Oligosaccharides; D037521:Virulence Factors