| 1. |
- Fu, Huamei, 1979, et al.
(author)
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Changes in the ratio between FPR and FPRL1 triggered superoxide production in human neutrophils-a tool in analysing receptor specific events
- 2008
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In: Journal of Immunological Methods. - : Elsevier BV. - 0022-1759. ; 331:1-2, s. 50-8
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Journal article (peer-reviewed)abstract
- Neutrophils express the G protein-coupled N-formyl peptide receptor (FPR) as well as its closely related homologue, formyl peptide like receptor 1 (FPRL1), and activation of these receptors induce a release of superoxide anions. The magnitude of the responses induced by the two peptide agonists fMLF and WKYMVM, specific for FPR and FPRL1, respectively, was found to be very variable in different neutrophil populations. The ratio between the FPR and FPRL1 triggered respiratory burst was, however, very constant and close to 1. The ratio was changed in neutrophils that were desensitized as well as when the signaling through either of the receptors was inhibited by receptor specific antagonists or by a PIP(2) binding peptide. The FPR/FPRL1 ratio was not changed in primed neutrophils or in differentiated HL-60 cells. We show that the change in the ratio, calculated from the amount of radical release in neutrophils triggered with FPR and FPRL1 specific agonists can be used as a valuable tool to find/identify receptor specific/selective changes mediated by peptides/proteins/drugs, as well as to identify cells from patients or groups of patients that diverge from normal cells in their FPR/FPRL1 triggered functions.
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| 2. |
- Bellner, Lars, 1973, et al.
(author)
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A Monocyte-Specific Peptide from Herpes Simplex Virus Type 2 Glycoprotein G Activates the NADPH-Oxidase but Not Chemotaxis through a G-Protein-Coupled Receptor Distinct from the Members of the Formyl Peptide Receptor Family.
- 2007
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In: Journal of immunology (Baltimore, Md. : 1950). - 0022-1767. ; 179:9, s. 6080-7
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Journal article (peer-reviewed)abstract
- We have recently identified a peptide derived from the secreted portion of the HSV-2 glycoprotein G, gG-2p20, to be proinflammatory. Based on its ability to activate neutrophils and monocytes via the formyl peptide receptor (FPR) to produce reactive oxygen species (ROS) that down-regulate NK cell function, we suggested it to be of importance in HSV-2 pathogenesis. We now describe the effects of an overlapping peptide, gG-2p19, derived from the same HSV-2 protein. Also, this peptide activated the ROS-generating NADPH-oxidase, however, only in monocytes and not in neutrophils. Surprisingly, gG-2p19 did not induce a chemotactic response in the affected monocytes despite using a pertussis toxin-sensitive, supposedly G-protein-coupled receptor. The specificity for monocytes suggested that FPR and its homologue FPR like-1 (FPRL1) did not function as receptors for gG-2p19, and this was also experimentally confirmed. Surprisingly, the monocyte-specific FPR homologue FPRL2 was not involved either, and the responsible receptor thus remains unknown so far. However, the receptor shares some basic signaling properties with FPRL1 in that the gG-2p19-induced response was inhibited by PBP10, a peptide that has earlier been shown to selectively inhibit FPRL1-triggered responses. We conclude that secretion and subsequent degradation of the HSV-2 glycoprotein G can generate several peptides that activate phagocytes through different receptors, and with different cellular specificities, to generate ROS with immunomodulatory properties.
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| 3. |
- Björkman, Lena, 1965, et al.
(author)
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Serum amyloid A mediates human neutrophil production of reactive oxygen species through a receptor independent of formyl peptide receptor like-1
- 2008
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In: Journal of Leukocyte Biology. - : Oxford University Press (OUP). - 0741-5400 .- 1938-3673. ; 83:2, s. 245-53
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Journal article (peer-reviewed)abstract
- Serum amyloid A (SAA) is one of the acute-phase reactants, a group of plasma proteins that increases immensely in concentration during microbial infections and inflammatory conditions, and a close relationship between SAA levels and disease activity in rheumatoid arthritis (RA) has been observed. RA is an inflammatory disease, where neutrophils play important roles, and SAA is thought to participate in the inflammatory reaction by being a neutrophil chemoattractant and inducer of proinflammatory cytokines. The biological effects of SAA are reportedly mediated mainly through formyl peptide receptor like-1 (FPRL1), a G protein-coupled receptor (GPCR) belonging to the formyl peptide receptor family. Here, we confirmed the affinity of SAA for FPRL1 by showing that stably transfected HL-60 cells expressing FPRL1 were activated by SAA and that the response was inhibited by the use of the FPRL1-specific antagonist WRWWWW (WRW4). We also show that SAA activates the neutrophil NADPH-oxidase and that a reserve pool of receptors is present in storage organelles mobilized by priming agents such as TNF-alpha and LPS from Gram-negative bacteria. The induced activity was inhibited by pertussis toxin, indicating the involvement of a GPCR. However, based on FPRL1-specific desensitization and use of FPRL1 antagonist WRW4, we found the SAA-mediated effects in neutrophils to be independent of FPRL1. Based on these findings, we conclude that SAA signaling in neutrophils is mediated through a GPCR, distinct from FPRL1. Future identification and characterization of the SAA receptor could lead to development of novel, therapeutic targets for treatment of RA.
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| 4. |
- Bray, Lucy, et al.
(author)
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Developing rights-based standards for children having tests, treatments, examinations and interventions : using a collaborative, multi-phased, multi-method and multi-stakeholder approach to build consensus
- 2023
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In: European Journal of Pediatrics. - : Springer Nature. - 0340-6199 .- 1432-1076.
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Journal article (peer-reviewed)abstract
- Children continue to experience harm when undergoing clinical procedures despite increased evidence of the need to improve the provision of child-centred care. The international ISupport collaboration aimed to develop standards to outline and explain good procedural practice and the rights of children within the context of a clinical procedure. The rights-based standards for children undergoing tests, treatments, investigations, examinations and interventions were developed using an iterative, multi-phased, multi-method and multi-stakeholder consensus building approach. This consensus approach used a range of online and face to face methods across three phases to ensure ongoing engagement with multiple stakeholders. The views and perspectives of 203 children and young people, 78 parents and 418 multi-disciplinary professionals gathered over a two year period (2020–2022) informed the development of international rights-based standards for the care of children having tests, treatments, examinations and interventions. The standards are the first to reach international multi-stakeholder consensus on definitions of supportive and restraining holds.Conclusion: This is the first study of its kind which outlines international rights-based procedural care standards from multi-stakeholder perspectives. The standards offer health professionals and educators clear evidence-based tools to support discussions and practice changes to challenge prevailing assumptions about holding or restraining children and instead encourage a focus on the interests and rights of the child.What is Known:• Children continue to experience short and long-term harm when undergoing clinical procedures despite increased evidence of the need to improve the provision of child-centred care.• Professionals report uncertainty and tensions in applying evidence-based practice to children’s procedural care. What is New:• This is the first study of its kind which has developed international rights-based procedural care standards from multi-stakeholder perspectives.• The standards are the first to reach international multi-stakeholder consensus on definitions of supportive and restraining holds.
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| 5. |
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En båge genom tiden - ritualer kring en göteborgshistoria. Om Flickläroverket i Artisten
- 2024
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Editorial collection (other academic/artistic)abstract
- 1929 bildades Göteborgs första Högre allmänna läroverk för Flickor – Flickläroverket som fick en byggnad 1935 i det kulturella centrumet, Götaplatsen. Efter några år som Kjellbergska gymnasiet, sedan Komvux, blev byggnaden del av Artisten, Högskolan för scen och musik, HSM 1992. Byggnaden har burit kvinnors utbildning, konst och kultur över många generationer, en minneskedja som nu är bruten. Boken - En båge genom tiden – ritualer kring en göteborgshistoria – en konst- och forskningsantologi – är resultatet av de offentliga minnesdagar där de deltagande drygt 200 kvinnorna (70– 97 år) som varit elever på Flickläroverket, studenter vid Artisten, konstnärer och forskare – bidrog till och deltog i gestaltande ritualer, minnesrum, dans, utställningar och samtal som gav liv åt en utbildningskultur och konst som berört samhället i generationer. I boken bidrar ett 20-tal Göteborgsbaserade konstnärer och forskare med olika perspektiv på byggnadens poetiska, sociala och konstnärliga dimensioner. Bland annat beskrivs återskapandet av Bågdansen, som dansades varje år vid Lucia mellan 1934-1972. Här beskrivs även den medie-debatt som ledde till räddningen av målningen Dansen av Nils Nilsson från 1935 och hur nedtagningen gick till. Tillsammans med ett rikt foto- och bildmaterial, filmdokumentationer och ett ljudarkiv utgör boken ett tidsdokument där konst fungerar som minnesbärare över tid och rum.
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| 6. |
- Flowers, Sarah A., et al.
(author)
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Decrease of core 2 O-glycans on synovial lubricin in osteoarthritis reduces galectin-3 mediated crosslinking
- 2020
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In: Journal of Biological Chemistry. - 0021-9258 .- 1083-351X. ; 295:47, s. 16023-16036
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Journal article (peer-reviewed)abstract
- The synovial fluid glycoprotein lubricin (also known as proteoglycan 4) is a mucin-type O-linked glycosylated biological lubricant implicated to be involved in osteoarthritis (OA) development. Lubricin's ability to reduce friction is related to its glycosylation consisting of sialylated and unsialylated Tn-antigens and core 1 and core 2 structures. The glycans on lubricin have also been suggested to be involved in crosslinking and stabilization of the lubricating superficial layer of cartilage by mediating interaction between lubricin and galectin-3. However, with the spectrum of glycans being found on lubricin, the glycan candidates involved in this interaction were unknown. Here, we confirm that the core 2 O-linked glycans mediate this lubricin-galectin-3 interaction, shown by surface plasmon resonance data indicating that recombinant lubricin (rhPRG4) devoid of core 2 structures did not bind to recombinant galectin-3. Conversely, transfection of Chinese hamster ovary cells with the core 2 GlcNAc transferase acting on a mucin-type O-glycoprotein displayed increased galectin-3 binding. Both the level of galectin-3 and the galectin-3 interactions with synovial lubricin were found to be decreased in late-stage OA patients, coinciding with an increase in unsialylated core 1 O-glycans (T-antigens) and Tn-antigens. These data suggest a defect in crosslinking of surface-active molecules in OA and provide novel insights into OA molecular pathology.
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| 7. |
- Forsman, Huamei, et al.
(author)
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The beta-galactoside binding immunomodulatory lectin galectin-3 reverses the desensitized state induced in neutrophils by the chemotactic peptide f-Met-Leu-Phe: role of reactive oxygen species generated by the NADPH-oxidase and inactivation of the agonist
- 2008
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In: Glycobiology. - : Oxford University Press (OUP). - 1460-2423 .- 0959-6658. ; 18:11, s. 905-12
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Journal article (peer-reviewed)abstract
- Neutrophils interacting with a chemoattractant gradually become nonresponsive to further stimulation by the same agonist, a process known as desensitization. Receptor desensitization is a highly regulated process that involves different mechanisms depending on which receptor-ligand pair that is studied. Galectin-3, a member of a large family of beta-galactoside-binding lectins, has been suggested to be a regulator of the inflammatory process, augmenting or directly triggering the neutrophil functional repertoire. We show here that the desensitized state of neutrophils interacting with the chemotactic peptide fMLF is broken by galectin-3 and that this is achieved through an oxygen radical-mediated inactivation of the chemoattractant. The effect was inhibited by the competitor lactose and required the affinity of galectin-3 for N-acetyllactosamine, a saccharide typically found on cell surface glycoproteins. The latter was shown using a galectin-3 mutant that lacked N-acetyllactosamine binding activity, and this protein was not active. The mechanism behind the inactivation of the chemoattractant was found to depend on the ability of galectin-3 to induce a neutrophil generation/secretion of reactive oxygen species which in combined action with myeloperoxidase inactivated the peptides.
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| 8. |
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| 9. |
- Fu, Huamei, 1979, et al.
(author)
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The two neutrophil members of the formylpeptide receptor family activate the NADPH-oxidase through signals that differ in sensitivity to a gelsolin derived phosphoinositide-binding peptide
- 2004
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In: BMC cell biology. - : Springer Science and Business Media LLC. - 1471-2121. ; 5:1
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Journal article (peer-reviewed)abstract
- BACKGROUND: The formylpeptide receptor family members FPR and FPRL1, expressed in myeloid phagocytes, belong to the G-protein coupled seven transmembrane receptor family (GPCRs). They share a high degree of sequence similarity, particularly in the cytoplasmic domains involved in intracellular signaling. The established model of cell activation through GPCRs states that the receptors isomerize from an inactive to an active state upon ligand binding, and this receptor transformation subsequently activates the signal transducing G-protein. Accordingly, the activation of human neutrophil FPR and FPRL1 induces identical, pertussis toxin-sensitive functional responses and a transient increase in intracellular calcium is followed by a secretory response leading to mobilization of receptors from intracellular stores, as well as a release of reactive oxygen metabolites. RESULTS: We report that a cell permeable ten amino acid peptide (PBP10) derived from the phosphatidylinositol 4,5-bisphosphate (PIP2) binding region of gelsolin (an uncapper of actin filaments) blocks granule mobilization as well as secretion of oxygen radicals. The inhibitory effect of PBP10 is, however, receptor specific and affects the FPRL1-, but not the FPR-, induced cellular response. The transient rise in intracellular calcium induced by the active receptors is not affected by PBP10, suggesting that the blockage occurs in a parallel, novel signaling pathway used by FPRL1 to induce oxygen radical production and secretion. Also the FPR can activate neutrophils through a PBP10-sensitive signaling pathway, but this signal is normally blocked by the cytoskeleton. CONCLUSIONS: This study demonstrates that the two very closely related chemoattractant receptors, FPR and FPRL1, use distinct signaling pathways in activation of human neutrophils. The PIP2-binding peptide PBP10 selectively inhibits FPRL1-mediated superoxide production and granule mobilization. Furthermore, the activity of this novel PBP10 sensitive pathway in neutrophils is modulated by the actin cytoskeleton network.
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| 10. |
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