title: Neuropeptide S and G protein-coupled receptor 154 modulate macrophage immune responses.
abstract: G protein-coupled receptor 154 (GPR154) is a recently discovered asthma susceptibility gene upregulated in the airways of asthma patients. We previously observed increased pulmonary mRNA expression of the murine ortholog Gpr154 in a mouse model of ovalbumin (OVA)-induced inflammation. However, the expression profile of GPR154 in leukocytes and the cellular functions of the receptor and its endogenous agonist neuropeptide S (NPS) have remained unidentified. Here, we characterized the mRNA expression of NPS and GPR154 by using real-time RT-PCR in fractionated human blood cells and in peripheral blood mononuclear cells (PBMCs) with monocyte or T cell activation. The expression of GPR154 in leukocytes was further confirmed by immunoblotting experiments and immunohistochemical staining of human sputum samples. Additionally, we characterized the expression of GPR154 in the lung tissue samples and in the bronchoalveolar lavage (BAL) fluid of OVA sensitized and challenged BALB/c mice. In human blood and sputum cells, monocyte/macrophages and eosinophils were identified as GPR154-positive cells. In PBMCs, monocyte activation with LPS but not T cell activation with anti-CD3/CD28 antibodies resulted in increased NPS and GPR154 expression. In the lung tissue samples and in the BAL fluid of OVA-challenged mice, GPR154 expression was upregulated in alveolar macrophages in comparison to controls. In the mouse macrophage RAW 264.7 cell line, NPS-stimulated Galphas- and Galphaq-dependent phagocytosis of Escherichia coli. The results show that GPR154 is upregulated in macrophages after antigen challenge and that NPS is capable of inducing phagocytosis of unopsonized bacteria.
authors.affiliation: Department of Medical Genetics, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland.
authors.forename: Ville
authors.initials: V
authors.lastname: Pulkkinen
authors.forename: Marja-Leena
authors.initials: ML
authors.lastname: Majuri
authors.forename: Guoying
authors.initials: G
authors.lastname: Wang
authors.forename: Päivi
authors.initials: P
authors.lastname: Holopainen
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Obase
authors.forename: Johanna
authors.initials: J
authors.lastname: Vendelin
authors.forename: Henrik
authors.initials: H
authors.lastname: Wolff
authors.forename: Paula
authors.initials: P
authors.lastname: Rytilä
authors.forename: Lauri A
authors.initials: LA
authors.lastname: Laitinen
authors.forename: Tari
authors.initials: T
authors.lastname: Haahtela
authors.forename: Tarja
authors.initials: T
authors.lastname: Laitinen
authors.forename: Harri
authors.initials: H
authors.lastname: Alenius
authors.forename: Juha
authors.initials: J
authors.lastname: Kere
authors.forename: Marko
authors.initials: M
authors.lastname: Rehn
mesh_terms: D000818:Animals; D001991:Bronchitis / Q000276:immunology; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D018106:CD28 Antigens / Q000276:immunology; D017252:CD3 Complex / Q000276:immunology; D002460:Cell Line; D004804:Eosinophils / Q000276:immunology; D004926:Escherichia coli / Q000276:immunology / Q000502:physiology; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000633:toxicity; D008168:Lung / Q000378:metabolism; D008213:Lymphocyte Activation; D008264:Macrophages / Q000276:immunology* / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D009479:Neuropeptides / Q000276:immunology*; D010587:Phagocytosis / Q000276:immunology; D043562:Receptors, G-Protein-Coupled / Q000276:immunology*; D013183:Sputum / Q000378:metabolism
chemical_list: D018106:CD28 Antigens; D017252:CD3 Complex; D008070:Lipopolysaccharides; C484532:NPSR1 protein, human; D009479:Neuropeptides; D043562:Receptors, G-Protein-Coupled; C506531:neuropeptide S, human