title: Immune homeostasis in the respiratory tract and its impact on heterologous infection.
abstract: Innate immunity at mucosal surfaces requires additional restraint to prevent inflammation to innocuous antigens or commensal microorganisms. The threshold above which airway macrophages become activated is raised by site-specific factors including the receptors for transforming growth factor beta, interleukin 10 and CD200; the ligands for which are produced by, or expressed on, respiratory epithelium. We discuss such site-specific regulation and how this is continually altered by prior infections. Resetting of innate reactivity represents a strategy for limiting excessive inflammation, but in some may pre-dispose to secondary bacterial pneumonia.
authors.affiliation: Imperial College London, National Heart and Lung Institute, Leukocyte Biology Section, Sir Alexander Fleming Building, Exhibition Road, London SW7 2AZ, United Kingdom.
authors.forename: Erika
authors.initials: E
authors.lastname: Wissinger
authors.forename: John
authors.initials: J
authors.lastname: Goulding
authors.forename: Tracy
authors.initials: T
authors.lastname: Hussell
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D000954:Antigens, Surface / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D001424:Bacterial Infections / Q000276:immunology*; D005786:Gene Expression Regulation; D006801:Humans; D007113:Immunity, Innate; D007156:Immunologic Memory; D016753:Interleukin-10 / Q000276:immunology; D016676:Macrophages, Alveolar / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D064446:Orexin Receptors; D011956:Receptors, Cell Surface / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D012137:Respiratory System / Q000276:immunology* / Q000382:microbiology; D016212:Transforming Growth Factor beta / Q000276:immunology
chemical_list: D015703:Antigens, CD; D000954:Antigens, Surface; C477337:CD200R1 protein, human; D064446:Orexin Receptors; D011956:Receptors, Cell Surface; D016212:Transforming Growth Factor beta; D016753:Interleukin-10; C042739:antigens, CD200