1. Surfactant protein-D modulation of pulmonary macrophage phenotype is controlled by S -nitrosylation.
- Author
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Guo CJ, Atochina-Vasserman EN, Abramova E, Smith LC, Beers MF, and Gow AJ
- Subjects
- Animals, Bronchoalveolar Lavage Fluid chemistry, Bronchoalveolar Lavage Fluid immunology, Chemokine CCL20 genetics, Chemokine CCL20 immunology, Chemokine CXCL1 genetics, Chemokine CXCL1 immunology, Cyclooxygenase 2 genetics, Cyclooxygenase 2 immunology, Female, Immunity, Innate, Interleukin-1beta genetics, Interleukin-1beta immunology, Lipopolysaccharides pharmacology, Lung immunology, Lung metabolism, Lung microbiology, Macrophages, Alveolar drug effects, Macrophages, Alveolar microbiology, Male, Mice, Mice, Inbred C57BL, NF-kappa B genetics, NF-kappa B immunology, Nitric Oxide Synthase Type II genetics, Nitric Oxide Synthase Type II immunology, Nitroso Compounds immunology, Phenotype, Pneumocystis growth & development, Pneumocystis pathogenicity, Pneumocystis Infections immunology, Pneumocystis Infections metabolism, Pneumocystis Infections microbiology, Pulmonary Surfactant-Associated Protein D genetics, Pulmonary Surfactant-Associated Protein D immunology, RAW 264.7 Cells, Tumor Necrosis Factor-alpha genetics, Tumor Necrosis Factor-alpha immunology, Vascular Cell Adhesion Molecule-1 genetics, Vascular Cell Adhesion Molecule-1 immunology, Macrophages, Alveolar immunology, Nitroso Compounds metabolism, Pneumocystis Infections genetics, Protein Processing, Post-Translational, Pulmonary Surfactant-Associated Protein D metabolism
- Abstract
Surfactant protein-D (SP-D) is a regulator of pulmonary innate immunity whose oligomeric state can be altered through S -nitrosylation to regulate its signaling function in macrophages. Here, we examined how nitrosylation of SP-D alters the phenotypic response of macrophages to stimuli both in vivo and in vitro. Bronchoalveolar lavage (BAL) from C57BL6/J and SP-D-overexpressing (SP-D OE) mice was incubated with RAW264.7 cells ± LPS. LPS induces the expression of the inflammatory genes Il1b and Nos2 , which is reduced 10-fold by SP-D OE-BAL. S -nitrosylation of the SP-D OE-BAL (SNO-SP-D OE-BAL) abrogated this inhibition. SNO-SP-D OE-BAL alone induced Il1b and Nos2 expression. PCR array analysis of macrophages incubated with SP-D OE-BAL (±LPS) shows increased expression of repair genes, Ccl20 , Cxcl1 , and Vcam1 , that was accentuated by LPS. LPS increases inflammatory gene expression, Il1a , Nos2 , Tnf , and Ptgs2 , which was accentuated by SNO-SP-D OE-BAL but inhibited by SP-D OE-BAL. The transcription factor NF-κB was identified as a target for SNO-SP-D by IPA, which was confirmed by Trans-AM ELISA in vitro. In vivo, SP-D overexpression increases the burden of infection in a Pneumocystis model while increasing cellular recruitment. Expression of iNOS and the production of NO metabolites were significantly reduced in SP-D OE mice relative to C57BL6/J. Inflammatory gene expression was increased in infected C57BL6/J mice but decreased in SP-D OE. SP-D oligomeric structure was disrupted in C57BL6/J infected mice but unaltered within SP-D OE. Thus SP-D modulates macrophage phenotype and the balance of multimeric to trimeric SP-D is critical to this regulation.
- Published
- 2019
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