| 1. |
- Löfdahl, Anna, et al.
(författare)
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5-HT2B receptor antagonists attenuate myofibroblast differentiation and subsequent fibrotic responses in vitro and in vivo
- 2016
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Ingår i: Physiological Reports. - : Wiley. - 2051-817X. ; 4:15
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Tidskriftsartikel (refereegranskat)abstract
- Pulmonary fibrosis is characterized by excessive accumulation of connective tissue, along with activated extracellular matrix (ECM)-producing cells, myofibroblasts. The pathological mechanisms are not well known, however serotonin (5-HT) and 5-HT class 2 (5-HT2) receptors have been associated with fibrosis. The aim of the present study was to investigate the role of 5-HT2B receptors in fibrosis, using small molecular 5-HT2B receptor antagonists EXT5 and EXT9, with slightly different receptor affinity. Myofibroblast differentiation [production of alpha-smooth muscle actin (α-SMA)] and ECM synthesis were quantified in vitro, and the effects of the receptor antagonists were evaluated. Pulmonary fibrosis was also modeled in mice by subcutaneous bleomycin administrations (under light isoflurane anesthesia), and the effects of receptor antagonists on tissue density, collagen-producing cells, myofibroblasts and decorin expression were investigated. In addition, cytokine expression was analyzed in serum. Lung fibroblasts displayed an increased α-SMA (P < 0.05) and total proteoglycan production (P < 0.01) when cultured with TGF-β1 together with 5-HT, which were significantly reduced with both receptor antagonists. Following treatment with EXT5 or EXT9, tissue density, expression of decorin, number of collagen-producing cells, and myofibroblasts were significantly decreased in vivo compared to bleomycin-treated mice. Receptor antagonization also significantly reduced systemic levels of TNF-α and IL-1β, indicating a role in systemic inflammation. In conclusion, 5-HT2B receptor antagonists have potential to prevent myofibroblast differentiation, in vitro and in vivo, with subsequent effect on matrix deposition. The attenuating effects of 5-HT2B receptor antagonists on fibrotic tissue remodeling suggest these receptors as novel targets for the treatment of pulmonary fibrosis.
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| 2. |
- Tykesson, Emil, et al.
(författare)
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Recombinant dermatan sulfate is a potent activator of heparin cofactor II-dependent inhibition of thrombin
- 2019
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Ingår i: Glycobiology. - : Oxford University Press (OUP). - 1460-2423. ; 29:6, s. 446-451
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Tidskriftsartikel (refereegranskat)abstract
- The glycosaminoglycan dermatan sulfate (DS) is a well-known activator of heparin cofactor II-dependent inactivation of thrombin. In contrast to heparin, dermatan sulfate has never been prepared recombinantly from material of non-animal origin. Here we report on the enzymatic synthesis of structurally well-defined DS with high anticoagulant activity. Using a microbial K4 polysaccharide and the recombinant enzymes DS-epimerase 1, dermatan 4-O-sulfotransferase 1, uronyl 2-O-sulfotransferase and N-acetylgalactosamine 4-sulfate 6-O-sulfotransferase, several new glycostructures have been prepared, such as a homogenously sulfated IdoA-GalNAc-4S polymer and its 2-O-, 6-O- and 2,6-O-sulfated derivatives. Importantly, the recombinant highly 2,4-O-sulfated DS inhibits thrombin via heparin cofactor II, approximately 20 times better than heparin, enabling manipulation of vascular and extravascular coagulation. The potential of this method can be extended to preparation of specific structures that are of importance for binding and activation of cytokines, and control of inflammation and metastasis, involving extravasation and migration.
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| 3. |
- Abdillahi, Suado M, et al.
(författare)
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The Pulmonary Extracellular Matrix Is a Bactericidal Barrier Against Haemophilus influenzae in Chronic Obstructive Pulmonary Disease (COPD) : Implications for an in vivo Innate Host Defense Function of Collagen VI
- 2018
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Ingår i: Frontiers in Immunology. - : Frontiers Media SA. - 1664-3224. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Non-typeable Haemophilus influenzae (NTHi) is a Gram-negative human commensal commonly residing in the nasopharynx of preschool children. It occasionally causes upper respiratory tract infection such as acute otitis media, but can also spread to the lower respiratory tract causing bronchitis and pneumonia. There is increasing recognition that NTHi has an important role in chronic lower respiratory tract inflammation, particularly in persistent infection in patients suffering from chronic obstructive pulmonary disease (COPD). Here, we set out to assess the innate protective effects of collagen VI, a ubiquitous extracellular matrix component, against NTHi infection in vivo. In vitro, collagen VI rapidly kills bacteria through pore formation and membrane rupture, followed by exudation of intracellular content. This effect is mediated by specific binding of the von Willebrand A (VWA) domains of collagen VI to the NTHi surface adhesins protein E (PE) and Haemophilus autotransporter protein (Hap). Similar observations were made in vivo specimens from murine airways and COPD patient biopsies. NTHi bacteria adhered to collagen fibrils in the airway mucosa and were rapidly killed by membrane destabilization. The significance in host-pathogen interplay of one of these molecules, PE, was highlighted by the observation that it confers partial protection from bacterial killing. Bacteria lacking PE were more prone to antimicrobial activity than NTHi expressing PE. Altogether the data shed new light on the carefully orchestrated molecular events of the host-pathogen interplay in COPD and emphasize the importance of the extracellular matrix as a novel branch of innate host defense.
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| 4. |
- Alaridah, Nader, et al.
(författare)
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Mycobacteria Manipulate G-Protein-Coupled Receptors to Increase Mucosal Rac1 Expression in the Lungs
- 2017
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Ingår i: Journal of Innate Immunity. - : S. Karger AG. - 1662-811X .- 1662-8128. ; 9, s. 318-329
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Tidskriftsartikel (refereegranskat)abstract
- Mycobacterium bovis bacille Calmette-Guérin (BCG) is currently the only approved vaccine against tuberculosis (TB). BCG mimics M. tuberculosis (Mtb) in its persistence in the body and is used as a benchmark to compare new vaccine candidates. BCG was originally designed for mucosal vaccination, but comprehensive knowledge about its interaction with epithelium is currently lacking. We used primary airway epithelial cells (AECs) and a murine model to investigate the initial events of mucosal BCG interactions. Furthermore, we analysed the impact of the G-protein-coupled receptors (GPCRs), CXCR1 and CXCR2, in this process, as these receptors were previously shown to be important during TB infection. BCG infection of AECs induced GPCR-dependent Rac1 up-regulation, resulting in actin redistribution. The altered distribution of the actin cytoskeleton involved the MAPK signalling pathway. Blocking of the CXCR1 or CXCR2 prior to infection decreased Rac1 expression, and increased epithelial transcriptional activity and epithelial cytokine production. BCG infection did not result in epithelial cell death as measured by p53 phosphorylation and annexin. This study demonstrated that BCG infection of AECs manipulated the GPCRs to suppress epithelial signalling pathways. Future vaccine strategies could thus be improved by targeting GPCRs.
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| 5. |
- Andersson Sjöland, Annika, et al.
(författare)
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Versican in inflammation and tissue remodelling: the impact on lung disorders.
- 2015
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Ingår i: Glycobiology. - : Oxford University Press (OUP). - 1460-2423 .- 0959-6658. ; 25:3, s. 243-251
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Forskningsöversikt (refereegranskat)abstract
- Versican is a proteoglycan that has many different roles in tissue homeostasis and inflammation. The biochemical structure is comprised of four different types of the core protein with attached glycosaminoglycans that can be sulphated to various extents and has the capacity to regulate differentiation of different cell types, migration, cell adhesion, proliferation, tissue stabilization and inflammation. Versican's regulatory properties are of importance during both homeostasis and changes that lead to disease progression. The glycosaminoglycans that are attached to the core protein are of the chondroitin sulfate/dermatan sulfate type and are known to be important in inflammation through interactions with cytokines and growth factors. For a more complex understanding of versican it is of importance to study the tissue niche, where the wound healing process in both healthy and diseased conditions take place. In previous studies our group has identified changes in the amount of the multifaceted versican in chronic lung disorders such as asthma, chronic obstructive pulmonary disease and bronchiolitis obliterans syndrome, which could be a result of pathologic, transforming growth factor β driven, on-going remodelling processes. Reversely, the context of versican in its niche is of great importance since versican has been reported to have a beneficial role in other contexts e.g. emphysema. Here we explore the vast mechanisms of versican in healthy lung and in lung disorders.
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| 6. |
- Andréasson, Kristofer, et al.
(författare)
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Limited impact of fibromodulin deficiency on the development of experimental skin fibrosis
- 2016
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Ingår i: Experimental Dermatology. - : Wiley. - 0906-6705.
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Tidskriftsartikel (refereegranskat)abstract
- Excessive production of collagen is the hallmark of fatal diseases of fibrosis such as systemic sclerosis. Overexpression of the proteoglycan fibromodulin (FMOD) has been associated with improved wound healing and scarless repair. In this study we have investigated the consequences of FMOD deficiency on the development of experimental skin fibrosis. Using immunohistochemistry, we identified FMOD in both human and murine fibrotic skin. In the bleomycin model of skin fibrosis, FMOD(-/-) mice developed skin fibrosis to a similar degree compared to FMOD(+/+) mice. Analysis of skin ultrastructure using transmission electron microscopy revealed a significant reduction in collagen fibril diameter in FMOD(-/-) but not FMOD(+/+) mice following fibrosis. We conclude that impact of FMOD deficiency on the development of experimental skin fibrosis is limited. This article is protected by copyright. All rights reserved.
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| 7. |
- Bagher, Mariam, et al.
(författare)
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Mast cells and mast cell tryptase enhance migration of human lung fibroblasts through protease-activated receptor 2
- 2018
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Ingår i: Cell Communication and Signaling. - : Springer Science and Business Media LLC. - 1478-811X. ; 16:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Mast cells may activate fibroblasts and contribute to remodeling processes in the lung. However, the mechanism behind these actions needs to be further investigated. Fibroblasts are major regulators of on-going remodeling processes. Protease activated receptor 2 (PAR2) expressed by fibroblasts may be activated by serine proteases, such as the mast cell mediator tryptase. The objective in this study was to investigate the effects of mast cells and specifically mast cell tryptase on fibroblast migration and the role of PAR2 activation. Methods: Human lung fibroblasts (HFL-1) were cultured together with human peripheral blood-derived mast cells or LAD2 mast cells and stimulated with either conditioned medium from LAD2 cells or tryptase. Analyses of immunological stimulation of mast cells by IgE/anti IgE in the co-culture system were also performed. The importance of PAR2 activation by mast cells and mast cell tryptase for the migratory effects of fibroblasts was investigated by pre-treatment with the PAR2 antagonist P2pal-18S. The expression of PAR2 was analyzed on fibroblasts and mast cells. Results: The migratory capacity of HFL-1 cells was enhanced by blood-derived mast cells (p < 0.02), LAD2 cells (p < 0.001), conditioned medium (p < 0.05) and tryptase (p < 0.006). P2pal-18S decreased the induced migration caused by mast cells (p < 0.001) and tryptase (p < 0.001) and the expression of PAR2 was verified in HFL-1 cells. Mast cells immunologically stimulated with IgE/Anti IgE had no further effects on fibroblast migration. Conclusions: Mast cells and the mast cell mediator tryptase may have crucial roles in inducing lung fibroblast migration via PAR-2 activation, which may contribute to remodeling processes in chronic lung diseases.
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| 8. |
- Blank Savukinas, Ulrika, et al.
(författare)
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The Bystander Effect : Mesenchymal Stem Cell-Mediated Lung Repair
- 2016
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Ingår i: Stem Cells. - : Oxford University Press (OUP). - 1549-4918 .- 1066-5099. ; 34:6, s. 1437-1444
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Forskningsöversikt (refereegranskat)abstract
- Mesenchymal stem or stromal cells (MSCs), a heterogeneous subset of adult stem/progenitor cells, have surfaced as potential therapeutic units with significant clinical benefit for a wide spectrum of disease conditions, including those affecting the lung. Although MSCs carry both self-renewal and multilineage differentiation abilities, current dogma holds that MSCs mainly contribute to tissue regeneration and repair by modulating the host tissue via secreted cues. Thus, the therapeutic benefit of MSCs is thought to derive from so called bystander effects. The regenerative mechanisms employed by MSCs in the lung include modulation of the immune system as well as promotion of epithelial and endothelial repair. Apart from secreted factors, a number of recent findings suggest that MSCs engage in mitochondrial transfer and shedding of membrane vesicles as a means to enhance tissue repair following injury. Furthermore, it is becoming increasingly clear that MSCs are an integral component of epithelial lung stem cell niches. As such, MSCs play an important role in coupling information from the environment to stem and progenitor populations, such that homeostasis can be ensured even in the face of injury. It is the aim of this review to outline the major mechanisms by which MSCs contribute to lung regeneration, synthesizing recent preclinical findings with data from clinical trials and potential for future therapy
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| 9. |
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| 10. |
- Burgess, Janette K, et al.
(författare)
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The extracellular matrix - the under-recognized element in lung disease?
- 2016
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Ingår i: Journal of Pathology. - : Wiley. - 0022-3417 .- 1096-9896. ; 240:4, s. 397-409
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Forskningsöversikt (refereegranskat)abstract
- The lung is composed of airways and lung parenchyma, and the extracellular matrix (ECM) contains the main building blocks of both components. The ECM provides physical support and stability to the lung, and as such it has in the past been regarded as an inert structure. More recent research has provided novel insights revealing that the ECM is also a bioactive environment that orchestrates the cellular responses in its environs. Changes in the ECM in the airway or parenchymal tissues are now recognized in the pathological profiles of many respiratory diseases, including asthma, chronic obstructive pulmonary disease (COPD), and idiopathic pulmonary fibrosis (IPF). Only recently have we begun to investigate whether these ECM changes result from the disease process, or whether they constitute a driving factor that orchestrates the pathological outcomes. This review summarizes our current knowledge of the alterations in the ECM in asthma, COPD, and IPF, and the contributions of these alterations to the pathologies. Emerging data suggest that alterations in the composition, folding or rigidity of ECM proteins may alter the functional responses of cells within their environs, and in so doing change the pathological outcomes. These characteristics highlight potential avenues for targeting lung pathologies in the future. This may ultimately contribute to a better understanding of chronic lung diseases, and novel approaches for finding therapeutic solutions. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
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