title: Human Cystic Fibrosis Macrophages Have Defective Calcium-Dependent Protein Kinase C Activation of the NADPH Oxidase, an Effect Augmented byBurkholderia cenocepacia.
abstract: Macrophage intracellular pathogen killing is defective in cystic fibrosis (CF), despite abundant production of reactive oxygen species (ROS) in lung tissue.Burkholderiaspecies can cause serious infection in CF and themselves affect key oxidase components in murine non-CF cells. However, it is unknown whether human CF macrophages have an independent defect in the oxidative burst and whetherBurkholderiacontributes to this defect in terms of assembly of the NADPH oxidase complex and subsequent ROS production. In this article, we analyze CF and non-CF human monocyte-derived macrophages (MDMs) for ROS production, NADPH assembly capacity, protein kinase C expression, and calcium release in response to PMA and CF pathogens. CF MDMs demonstrate a nearly 60% reduction in superoxide production after PMA stimulation compared with non-CF MDMs. Although CF MDMs generally have increased total NADPH component protein expression, they demonstrate decreased expression of the calcium-dependent protein kinase C conventional subclass α/β leading to reduced phosphorylation of NADPH oxidase components p47phoxand p40phoxin comparison with non-CF MDMs. Ingestion ofB. cenocepaciaindependently contributes to and worsens the overall oxidative burst deficits in CF MDMs compared with non-CF MDMs. Together, these results provide evidence for inherent deficits in the CF macrophage oxidative burst caused by decreased phosphorylation of NADPH oxidase cytosolic components that are augmented byBurkholderiaThese findings implicate a critical role for defective macrophage oxidative responses in persistent bacterial infections in CF and create new opportunities for boosting the macrophage immune response to limit infection.
authors.affiliation: Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, OH 43205.
authors.forename: Kaivon
authors.initials: K
authors.lastname: Assani
authors.affiliation: Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, OH 43205.
authors.forename: Chandra L
authors.initials: CL
authors.lastname: Shrestha
authors.affiliation: Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, OH 43205.
authors.forename: Frank
authors.initials: F
authors.lastname: Robledo-Avila
authors.affiliation: Center for Microbial Interface Biology, Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH 43210; and.
authors.forename: Murugesan V
authors.identifier: 0000-0002-1515-1122
authors.initials: MV
authors.lastname: Rajaram
authors.affiliation: Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, OH 43205.
authors.forename: Santiago
authors.identifier: 0000-0003-2996-9440
authors.initials: S
authors.lastname: Partida-Sanchez
authors.affiliation: Center for Microbial Interface Biology, Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH 43210; and.
authors.forename: Larry S
authors.initials: LS
authors.lastname: Schlesinger
authors.affiliation: Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, OH 43205; benjamin.kopp@NationwideChildrens.org.|Center for Microbial Interface Biology, Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH 43210; and.|Section of Pediatric Pulmonology, Nationwide Children's Hospital, Columbus, OH 43205.
authors.forename: Benjamin T
authors.identifier: 0000-0002-2021-7990
authors.initials: BT
authors.lastname: Kopp
mesh_terms: D000818:Animals; D019121:Burkholderia Infections / Q000276:immunology*; D057508:Burkholderia cenocepacia / Q000276:immunology*; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D003550:Cystic Fibrosis / Q000276:immunology*; D015536:Down-Regulation; D006801:Humans; D008264:Macrophages / Q000276:immunology*; D051379:Mice; D019255:NADPH Oxidases / Q000378:metabolism*; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D016897:Respiratory Burst
chemical_list: D017382:Reactive Oxygen Species; D019255:NADPH Oxidases; D011493:Protein Kinase C; D002118:Calcium