title: Flagellin administration protects respiratory tract from Burkholderia cepacia infection.
abstract: Burkholderia cepacia is an important pathogen that often causes pneumonia in immunocompromised individuals. Here, it was demonstrated that the TLR5 agonist flagellin could locally activate innate immunity. This was characterized by rapid expressions of IL-1beta, TNF-alpha, and iNOS mRNA and a delay in the expression of IL-10 mRNA. A significant elevation in the IL-1beta, TNF-alpha, and nitric oxide levels was also noted. In the respiratory tract, flagellin induced neutrophil infiltration into the airways, which was observed by histopathological examination and confirmed by the neutrophil count and level of myeloperoxidase activity. This was concomitant with a high activity of alveolar macrophages that engulfed and killed B. cepacia in vitro. The flagellin mucosal treatment improved the B. cepacia clearance in the mouse lung. Thus, the present findings illustrate the profound stimulatory effect of flagellin on the lung mucosal innate immunity, a response that needs to be exploited therapeutically to prevent the development of respiratory tract infection by B. cepacia.
authors.affiliation: Department of Biology, College of Science, Baghdad University, Baghdad, 00964 Iraq. Ayaid_khadem@yahoo.com
authors.forename: Ayaid Khadem
authors.initials: AK
authors.lastname: Zgair
mesh_terms: D000818:Animals; D001428:Bacterial Vaccines / Q000008:administration & dosage / Q000276:immunology*; D019121:Burkholderia Infections / Q000276:immunology / Q000517:prevention & control*; D016956:Burkholderia cepacia / Q000276:immunology*; D005408:Flagellin / Q000008:administration & dosage / Q000276:immunology*; D015870:Gene Expression; D006651:Histocytochemistry; D016753:Interleukin-10 / Q000096:biosynthesis; D053583:Interleukin-1beta / Q000096:biosynthesis; D016676:Macrophages, Alveolar / Q000276:immunology; D051379:Mice; D009504:Neutrophils / Q000276:immunology; D052247:Nitric Oxide Synthase Type II / Q000096:biosynthesis; D009195:Peroxidase / Q000378:metabolism; D012137:Respiratory System / Q000276:immunology / Q000473:pathology; D012141:Respiratory Tract Infections / Q000276:immunology / Q000517:prevention & control*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D001428:Bacterial Vaccines; D053583:Interleukin-1beta; D014409:Tumor Necrosis Factor-alpha; D005408:Flagellin; D016753:Interleukin-10; D009195:Peroxidase; D052247:Nitric Oxide Synthase Type II