title: cIAP-1 controls innate immunity to C. pneumoniae pulmonary infection.
abstract: The resistance of epithelial cells infected with Chlamydophila pneumoniae for apoptosis has been attributed to the induced expression and increased stability of anti-apoptotic proteins called inhibitor of apoptosis proteins (IAPs). The significance of cellular inhibitor of apoptosis protein-1 (cIAP-1) in C. pneumoniae pulmonary infection and innate immune response was investigated in cIAP-1 knockout (KO) mice using a novel non-invasive intra-tracheal infection method. In contrast to wildtype, cIAP-1 knockout mice failed to clear the infection from their lungs. Wildtype mice responded to infection with a strong inflammatory response in the lung. In contrast, the recruitment of macrophages was reduced in cIAP-1 KO mice compared to wildtype mice. The concentration of Interferon gamma (IFN-gamma) was increased whereas that of Tumor Necrosis Factor (TNF-alpha) was reduced in the lungs of infected cIAP-1 KO mice compared to infected wildtype mice. Ex vivo experiments on mouse peritoneal macrophages and splenocytes revealed that cIAP-1 is required for innate immune responses of these cells. Our findings thus suggest a new immunoregulatory role of cIAP-1 in the course of bacterial infection.
authors: Department of Molecular Biology, Max Planck Institute for Infection Biology, Charitéplatz 1, Berlin, Germany.
authors: Hridayesh
authors: H
authors: Prakash
authors: Daniel
authors: D
authors: Becker
authors: Linda
authors: L
authors: Böhme
authors: Lori
authors: L
authors: Albert
authors: Martin
authors: M
authors: Witzenrath
authors: Simone
authors: S
authors: Rosseau
authors: Thomas F
authors: TF
authors: Meyer
authors: Thomas
authors: T
authors: Rudel
mesh_terms: D000818:Animals; D002690:Chlamydia Infections / Q000276:immunology* / Q000382:microbiology; D016993:Chlamydophila pneumoniae / Q000276:immunology* / Q000302:isolation & purification; D007113:Immunity, Innate / Q000502:physiology*; D051034:Inhibitor of Apoptosis Proteins / Q000502:physiology*; D007371:Interferon-gamma / Q000378:metabolism; D008171:Lung Diseases / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology; D017737:Macrophages, Peritoneal / Q000276:immunology; D051379:Mice; D018345:Mice, Knockout; D009569:Nitric Oxide / Q000096:biosynthesis; D013154:Spleen / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D051034:Inhibitor of Apoptosis Proteins; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; D007371:Interferon-gamma