title: The middle ear immune defense changes with age.
abstract: Otitis media is a common disease in childhood. In adults, the disease is relatively rare, but more frequently associated with complications. Possible reasons for this discrepancy are age-related differences in pathogen exposure, anatomy of the Eustachian tube and immune system. The objective of this study was to analyze the relationship between age and the mucosal immune system in the middle ear. It is hypothesized that genes involved in the middle ear immune system will change with age. A comprehensive assessment of these genetic differences using the techniques of complementary DNA has not been performed. Complementary DNA microarray technology was used to identify immune-related genes differentially expressed between the normal middle ear mucosa of young (10 days old) and adult rats (80 days old). Data were analyzed using tools of bioinformatics. A total of 260 age-related genes were identified, of which 51 genes were involved in the middle ear mucosal immune system. Genes related to the innate immune system, including alpha-defensin, calcium-binding proteins S100A9 and S100A8, were upregulated in young rats, whereas genes related to the adaptive immune system, including CD3 molecules, zeta-chain T-cell receptor-associated protein kinase and linker of activated T-cells, were upregulated in the adult. This study concludes that the normal middle ear immune system changes with age. Genes related to the innate immune system are upregulated in young rats, whereas genes related to the adaptive immune system are upregulated in adults.
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery and Audiology, Copenhagen University Hospital Rigshospitalet, 2100, Copenhagen, Denmark. mcras@hotmail.com.
authors.forename: Michelle Christine
authors.initials: MC
authors.lastname: Nielsen
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery and Audiology, Copenhagen University Hospital Rigshospitalet, 2100, Copenhagen, Denmark.
authors.forename: Morten
authors.initials: M
authors.lastname: Friis
authors.affiliation: Department of Biology and Biotech Research and Innovation Centre, Faculty of Science, The Bioinformatics Centre, University of Copenhagen, 2100, Copenhagen, Denmark.
authors.forename: Tomas
authors.initials: T
authors.lastname: Martin-Bertelsen
authors.affiliation: Department of Biology and Biotech Research and Innovation Centre, Faculty of Science, The Bioinformatics Centre, University of Copenhagen, 2100, Copenhagen, Denmark.|DTU Compute, Technical University of Denmark, 2800, Copenhagen, Denmark.
authors.forename: Ole
authors.initials: O
authors.lastname: Winther
authors.affiliation: Center for Genomic Medicine, Rigshospitalet, University of Copenhagen, 2100, Copenhagen, Denmark.
authors.forename: Lennart
authors.initials: L
authors.lastname: Friis-Hansen
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery and Audiology, Copenhagen University Hospital Rigshospitalet, 2100, Copenhagen, Denmark.|Faculty of Health and Medical Sciences, University of Copenhagen, 2900, Copenhagen, Denmark.
authors.forename: Per
authors.initials: P
authors.lastname: Cayé-Thomasen
mesh_terms: D056704:Adaptive Immunity / Q000235:genetics; D000375:Aging / Q000276:immunology*; D000818:Animals; D004432:Ear, Middle / Q000276:immunology*; D007113:Immunity, Innate / Q000235:genetics; D009092:Mucous Membrane / Q000276:immunology* / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D011919:Rats, Inbred Strains; D015854:Up-Regulation
keywords: Age related; Immune system; Microarray analysis; Middle ear; Rat bulla