umu.sePublications
Change search
Refine search result
1 - 10 of 10
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Ermert, David
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Bacteriology.
    Niemiec, Maria Joanna
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Bacteriology.
    Röhm, Marc
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Bacteriology.
    Glenthøj, Andreas
    Department of Hematology, National University Hospital, Copenhagen, Denmark..
    Borregaard, Niels
    Department of Hematology, National University Hospital, Copenhagen, Denmark..
    Urban, Constantin F.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Bacteriology.
    Candida albicans escapes from mouse neutrophils2013In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 94, no 2, p. 223-236Article in journal (Refereed)
    Abstract [en]

    Candida albicans, the most commonly isolated human fungal pathogen, is able to grow as budding yeasts or filamentous forms, such as hyphae. The ability to switch morphology has been attributed a crucial role for the pathogenesis of C. albicans. To mimic disseminated candidiasis in humans, the mouse is the most widely used model organism. Neutrophils are essential immune cells to prevent opportunistic mycoses. To explore potential differences between the rodent infection model and the human host, we compared the interactions of C. albicans with neutrophil granulocytes from mice and humans. We revealed that murine neutrophils exhibited a significantly lower ability to kill C. albicans than their human counterparts. Strikingly, C. albicans yeast cells formed germ tubes upon internalization by murine neutrophils, eventually rupturing the neutrophil membrane and thereby, killing the phagocyte. On the contrary, growth and subsequent escape of C. albicans are blocked inside human neutrophils. According to our findings, this blockage in human neutrophils might be a result of higher levels of MPO activity and the presence of α-defensins. We therefore outline differences in antifungal immune defense between humans and mouse strains, which facilitates a more accurate interpretation of in vivo results.

  • 2.
    Hosseinzadeh, Ava
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology. Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR). Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS).
    Thompson, Paul R.
    Segal, Brahm H.
    Urban, Constantin F.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology. Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR). Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS).
    Nicotine induces neutrophil extracellular traps2016In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 100, no 5, p. 1105-1112Article in journal (Refereed)
    Abstract [en]

    NETs serve to ensnare and kill microbial pathogens. However, NETs can at the same time contribute to tissue damage and excessive inflammation. Nicotine is a major toxic agent and has been associated with exacerbated inflammatory diseases. The current study aimed at investigating the role of nicotine, the addictive component of tobacco and electronic cigarettes, on triggering NET formation. We report that nicotine induces neutrophils to release NETs in a dose-dependent manner. Nicotine-induced NET formation is mediated via nicotine acetylcholine receptors, depends on Akt and PAD4 activation, but is Nox2-independent, as demonstrated by pharmacological inhibition of Nox2 and by use of Nox2-deficient mouse neutrophils. These findings demonstrate that nicotine induces NETs, which may in turn contribute to smoking-related diseases.

  • 3. Lampinen, Maria
    et al.
    Fredricsson, Annika
    Vessby, Johan
    Martinez, Johana Fernandez
    Wanders, Alkwin
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Rorsman, Fredrik
    Carlson, Marie
    Downregulated eosinophil activity in ulcerative colitis with concomitant primary sclerosing cholangitis2018In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 104, no 1, p. 173-183Article in journal (Refereed)
    Abstract [en]

    Primary sclerosing cholangitis (PSC) is a chronic bile duct inflammation strongly connected to ulcerative colitis (UC). PSC is associated with an increased risk of colon cancer, but the link between the intestinal and the bile duct inflammation is still unknown. Also, the involvement of intestinal immune cells in the pathogenesis of PSC remains to be determined. The eosinophil granulocyte is one of the immune cells implicated in the inflammatory process of ulcerative colitis. This study was performed to determine how the accumulation and activation of intestinal eosinophils may differ between UC with and without concomitant PSC, and how this may be influenced by the cytokine/chemokine profile of the intestinal compartment. Eosinophils from peripheral blood and multiple parts of the colon were analyzed by flow cytometry. The intestinal level of inflammatory mediators was assessed using a multiplex proximity extension assay and a quantitative immunoassay. We found that colonic eosinophils were more abundant in both UC and PSC-UC compared with controls, but that their expression of activation markers was significantly increased in UC only. The colonic level of pro-inflammatory cytokines was increased in active UC but not in PSC-UC. In conclusion, we show for the first time that eosinophil activation phenotype discriminates between UC and PSC-UC, and that this may depend on the local cytokine profile of the colonic mucosa. Lower expression of activation markers on eosinophils in UC with concomitant PSC may depend on the local protein profile of the colonic mucosa.

  • 4. Lepzien, Rico
    et al.
    Rankin, Gregory
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Medicine.
    Pourazar, Jamshid
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Medicine.
    Muala, Ala
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Medicine.
    Eklund, Anders
    Grunewald, Johan
    Blomberg, Anders
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Medicine.
    Smed-Sorensen, Anna
    Mapping mononuclear phagocytes in blood, lungs, and lymph nodes of sarcoidosis patients2019In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 105, no 4, p. 797-807Article in journal (Refereed)
    Abstract [en]

    Sarcoidosis is a T-cell driven inflammatory disease characterized by granuloma formation. Mononuclear phagocytes (MNPs)-macrophages, monocytes, and dendritic cells (DCs)-are likely critical in sarcoidosis as they initiate and maintain T cell activation and contribute to granuloma formation by cytokine production. Granulomas manifest primarily in lungs and lung-draining lymph nodes (LLNs) but these compartments are less studied compared to blood and bronchoalveolar lavage (BAL). Sarcoidosis can present with an acute onset (usually Lofgren's syndrome (LS)) or a gradual onset (non-LS). LS patients typically recover within 2 years while 60% of non-LS patients maintain granulomas for up to 5 years. Here, four LS and seven non-LS patients underwent bronchoscopy with endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). From each patient, blood, BAL, endobronchial biopsies (EBBs), and LLN samples obtained by EBUS-TBNA were collected and MNPs characterized using multicolor flow cytometry. Six MNP subsets were identified at varying frequencies in the anatomical compartments investigated. Importantly, monocytes and DCs were most mature with migratory potential in BAL and EBBs but not in the LLNs suggesting heterogeneity in MNPs in the compartments typically affected in sarcoidosis. Additionally, in LS patients, frequencies of DC subsets were lower or lacking in LLNs and EBBs, respectively, compared to non-LS patients that may be related to the disease outcome. Our work provides a foundation for future investigations of MNPs in sarcoidosis to identify immune profiles of patients at risk of developing severe disease with the aim to provide early treatment to slow down disease progression.

  • 5. Remen, Kirsten M. Robertson
    et al.
    Lerner, Ulf H.
    Umeå University, Faculty of Medicine, Department of Odontology, School of Dentistry.
    Gustafsson, Jan-Åke
    Andersson, Göran
    Activation of the liver X receptor-beta potently inhibits osteoclastogenesis from lipopolysaccharide-exposed bone marrow-derived macrophages2013In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 93, no 1, p. 71-82Article in journal (Refereed)
    Abstract [en]

    Bacterial-induced bone diseases, such as periodontitis and osteomyelitis, are chronic inflammatory diseases characterized by increased bone destruction as a result of enhanced osteoclastogenesis. The LXR alpha and -beta are important modulators of inflammatory signaling and can potently inhibit RANKL-induced osteoclast differentiation. Here, we investigated the effects of the LXR agonist GW3965 on LPS-induced osteoclast differentiation. Mouse BMMs primed with RANKL for 24 h, then exposed to LPS in the presence of GW3965 for 4 days, formed significantly fewer and smaller TRAP(+)-multinucleated osteoclasts with reduced expression of osteoclast markers (Acp5, Ctsk, Mmp-9, Dc-stamp, and Itg beta 3), along with inhibition of actin ring development. GW3965 was able to repress proinflammatory cytokine (TNF-alpha, IL-1 beta, IL-6, and IL-12p40) expression in BMMs exposed to LPS alone; however, once BMMs entered the osteoclast lineage following RANKL priming, GW3965 no longer inhibited cytokine expression. The inhibitory action of GW3965 involved the Akt pathway but seemed to be independent of MAPKs (p38, ERK, JNK) and NF-kappa B signaling. GW3965 acted in a LXR beta-dependent mechanism, as osteoclast differentiation was not inhibited in BMMs derived from LXR beta-/- mice. Finally, activation of LXR also inhibited differentiation in LPS-exposed mouse RAW264.7 cells. In conclusion, GW3965 acts through LXR beta to potently inhibit osteoclast differentiation from RANKL-primed BMMs in a LPS environment. In this respect, activation of the LXR could have a beneficial, therapeutic effect in the prevention of bacterial-induced bone erosion. 

  • 6. Robertson Remen, K. M.
    et al.
    Lerner, Ulf H.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Gustafsson, J.
    Andersson, G.
    Activation of the liver X receptor-β potently inhibits osteoclastogenesis from lipopolysaccharide-exposed bone marrowderived macrophages2013In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 93, no 1, p. 71-82Article in journal (Refereed)
    Abstract [en]

    Bacterial-induced bone diseases, such as periodontitis and osteomyelitis, are chronic inflammatory diseases characterized by increased bone destruction as a result of enhanced osteoclastogenesis. The LXRα and -β are important modulators of inflammatory signaling and can potently inhibit RANKL-induced osteoclast differentiation. Here, we investigated the effects of the LXR agonist GW3965 on LPS-induced osteoclast differentiation. Mouse BMMs primed with RANKL for 24 h, then exposed to LPS in the presence of GW3965 for 4 days, formed significantly fewer and smaller TRAP+-multinucleated osteoclasts with reduced expression of osteoclast markers (Acp5, Ctsk, Mmp-9, Dc-stamp, and Itgβ3), along with inhibition of actin ring development. GW3965 was able to repress proinflammatory cytokine (TNF-α, IL-1β, IL-6, and IL-12p40) expression in BMMs exposed to LPS alone; however, once BMMs entered the osteoclast lineage following RANKL priming, GW3965 no longer inhibited cytokine expression. The inhibitory action of GW3965 involved the Akt pathway but seemed to be independent of MAPKs (p38, ERK, JNK) and NF-κB signaling. GW3965 acted in a LXRβ- dependent mechanism, as osteoclast differentiation was not inhibited in BMMs derived from LXRβ-/- mice. Finally, activation of LXR also inhibited differentiation in LPS-exposed mouse RAW264.7 cells. In conclusion, GW3965 acts through LXRβ to potently inhibit osteoclast differentiation from RANKL-primed BMMs in a LPS environment. In this respect, activation of the LXR could have a beneficial, therapeutic effect in the prevention of bacterial-induced bone erosion.

  • 7.
    Stenberg, Åsa
    et al.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Histology and Cell Biology.
    Sehlin, Janove
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Histology and Cell Biology.
    Oldenborg, Per-Arne
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Histology and Cell Biology.
    Neutrophil apoptosis is associated with loss of signal regulatory protein alpha (SIRP alpha) from the cell surface2013In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 93, no 3, p. 403-412Article in journal (Refereed)
    Abstract [en]

    Cells of the innate immune system, including monocytes, macrophages, and neutrophils, play a major role in the development of inflammatory diseases. During inflammation, large numbers of neutrophils are recruited from the blood and subsequently undergo apoptosis, which involves changes in the cell surface expression of a number of receptors. Neutrophils express the Ig superfamily member, SIRP alpha, which is a receptor involved in regulating cell adhesion and migration. As apoptotic neutrophils down-regulate their capacity for adhesion and migration, we here investigated whether neutrophil expression of SIRP alpha was affected during apoptosis. We found that apoptotic neutrophils lost SIRP alpha from their cell surface with kinetics similar to the loss of CD16. The majority of neutrophils with reduced SIRP alpha also expressed PS on their surface, and the loss of the receptor was reduced proportional to the reduction of apoptosis by caspase inhibitors during Fas-induced apoptosis but less so during spontaneous apoptosis. Neutrophil loss of SIRP alpha or CD16 was inhibited by the protease inhibitor TAPI-2, as well as specific inhibitors of MMP3 or -8, suggesting that proteolytic mechanisms were involved. Finally, SIRP alpha was also found on smaller membrane vesicles released from the cells during apoptosis. Our data suggest that neutrophils reduce their SIRP alpha expression during apoptosis, which may be part of the functional down-regulation seen in apoptotic neutrophils. J. Leukoc. Biol. 93: 403-412; 2013.

  • 8.
    Strålberg, Fredrik
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology, Molecular Periodontology.
    Kassem, Ali
    Umeå University, Faculty of Medicine, Department of Odontology, Molecular Periodontology.
    Kasprzykowski, Franciszek
    Abrahamson, Magnus
    Grubb, Anders
    Lindholm, Catharina
    Lerner, Ulf H.
    Umeå University, Faculty of Medicine, Department of Odontology, Molecular Periodontology.
    Inhibition of lipopolysaccharide-induced osteoclast formation and bone resorption in vitro and in vivo by cysteine proteinase inhibitors2017In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 101, no 5, p. 1233-1243Article in journal (Refereed)
    Abstract [en]

    Inflammation-induced bone destruction is a major treatment target in many inflammatory skeletal diseases. The aim of this study was to investigate if the cysteine proteinase inhibitors cystatin C, fungal cysteine proteinase inhibitor (E-64), and N-benzyloxycarbonyl-arginylleucyl-valyl-glycyl-diazomethane acetate (Z-RLVG-CHN2) can inhibit LPS-induced osteoclast formation. Mouse bone marrow macrophages (BMMs) were isolated and primed with receptor activator of NF-kappa B ligand (RANKL) for 24 h, followed by stimulation with LPS, with and without inhibitors. Adult mice were injected locally with LPS and then treated with E-64 and osteoclast formation assessed by the number of cathepsin K+ multinucleated cells. Cystatin C inhibited LPS-induced osteoclast formation time and concentration dependently (IC50 = 0.3 mu M). The effect was associated with decreased mRNA and protein expression of tartrate-resistant acid phosphatase (TRAP) and cathepsin K and of the osteoclastogenic transcription factors c-Fos and NFATc1. LPS-induced osteoclast formation on bone slices was also inhibited by cystatin C, resulting in decreased pit formation and release of bone matrix proteins. Similar data were obtained with E-64 and Z-RLVG-CHN2. Cystatin C was internalized in BMMs stimulated by LPS but not in unstimulated BMMs. Osteoclast formation induced by LPS was dependent on TNF-alpha, and the 3 inhibitors abolished LPS-induced TNF superfamily 2 (gene encoding TNF-alpha; Tnfsf2) mRNA expression without affecting Il1b, Il6, or oncostatin M (Osm) expression. Formation of osteoclasts in the skull bones after local LPS stimulation was inhibited by E-64. It is concluded that cysteine proteinase inhibitors effectively inhibit LPS-induced osteoclast formation in vivo and in vitro by inhibition of TNF-alpha expression. The targeting of cysteine proteinases might represent a novel treatment modality for prevention of inflammatory bone loss.

  • 9. Ulvila, Johanna
    et al.
    Vanha-aho, Leena-Maija
    Kleino, Anni
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Vähä-Mäkilä, Mari
    Vuoksio, Milka
    Eskelinen, Sinikka
    Hultmark, Dan
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Kocks, Christine
    Hallman, Mikko
    Parikka, Mataleena
    Rämet, Mika
    Cofilin regulator 14-3-3zeta is an evolutionarily conserved protein required for phagocytosis and microbial resistance2011In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 89, no 5, p. 649-659Article in journal (Refereed)
    Abstract [en]

    Phagocytosis is an ancient cellular process that plays an important role in host defense. In Drosophila melanogaster phagocytic, macrophage-like hemocytes recognize and ingest microbes. We performed an RNAi-based in vitro screen in the Drosophila hemocyte cell line S2 and identified Abi, cpa, cofilin regulator 14-3-3ζ, tlk, CG2765, and CG15609 as mediators of bacterial phagocytosis. Of these identified genes, 14-3-3ζ had an evolutionarily conserved role in phagocytosis: bacterial phagocytosis was compromised when 14-3-3ζ was targeted with RNAi in primary Drosophila hemocytes and when the orthologous genes Ywhab and Ywhaz were silenced in zebrafish and mouse RAW 264.7 cells, respectively. In Drosophila and zebrafish infection models, 14-3-3ζ was required for resistance against Staphylococcus aureus. We conclude that 14-3-3ζ is essential for phagocytosis and microbial resistance in insects and vertebrates.

  • 10. Łyszkiewicz, Marcin
    et al.
    Zietara, Natalia
    Rohde, Manfred
    Gekara, Nelson O
    Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS). Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Jabłońska, Jadwiga
    Dittmar, Kurt E
    Weiss, Siegfried
    SIGN-R1+MHC II+ cells of the splenic marginal zone: a novel type of resident dendritic cells2011In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 89, no 4, p. 607-615Article in journal (Refereed)
    Abstract [en]

    In the spleen, the MZ forms an interface between red and white pulp. Its major function is to trap blood-borne antigens and to reorient them to APCs and lymphocytes. SIGN-R1(+) cells are of the MZ inherent cell population, which for a long time, have been considered as macrophages. We now show that one subpopulation of SIGN-R1(+) cells that express MHC II molecules should be considered as a resident DC. Histological analysis indicated that SIGN-R1(+) cells have dendritic-like protrusions extending into T and B cell areas. Flow cytometry analysis revealed an expression profile of adhesion, costimulatory, and MHC molecules similar to cDCs but distinct from macrophages. Most importantly, SIGN-R1(+)MHC(+) cells were able to present antigen to naïve CD4 T cells, as well as to cross-present soluble, particulate antigens secreted by Listeria monocytogenes to CD8 T cells in vitro and in vivo. Our experiments identified SIGN-R1(+)MHC II(+) cells as professional APCs and indicate their nature as splenic resident DCs.

1 - 10 of 10
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf