| 1. |
- Greiff, Lennart, et al.
(author)
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Effects of topical platelet activating factor on the guinea-pig tracheobronchial mucosa in vivo
- 1997
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In: Acta Physiologica Scandinavica. - 0001-6772. ; 160:4, s. 387-391
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Journal article (peer-reviewed)abstract
- Platelet activating factor (PAF) has been reported to produce a variety of airway effects including epithelial damage and increased airway-lung absorption of hydrophilic tracers. The present study examines effects of PAF on the guinea-pig tracheobronchial mucosa in vivo. Vehicle with and without PAF (4.0 and 8.0 nmol) was superfused onto the tracheobronchial mucosa. The levels of 125I-albumin, previously given intravenously, were determined in tracheobronchial lavage fluids as an index of mucosal exudation of plasma. The mucosa was also examined by scanning electron microscopy. In separate animals, 99mTc-DTPA (a low molecular weight, 492 Da, hydrophilic tracer) was superfused onto the mucosal surface through an oro-tracheal catheter, together with vehicle or PAF (8.0 nmol). A gamma camera determined the disappearance rate of 99mTc-DTPA from the airways as an index of mucosal absorption. PAF produced dose-dependent mucosal exudation of plasma up to 20-fold greater than control (P < 0.001). However, PAF did not damage the epithelium and the absorption ability of the airway mucosa was unaffected. The results, in contrast to previous reports, suggest that PAF may not readily damage the airway mucosa even at large exudative doses of the agent. The present finding support the view that the plasticity of the epithelial junctions allows the creation of valve-like paracellular pathways for unidirectional clearance of extravasated plasma into the airway lumen. We suggest that endogenous PAF may participate in first line respiratory defence reactions by causing lumenal entry of bulk plasma without harming the epithelium.
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| 2. |
- Korsgren, Magnus, et al.
(author)
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Neural expression and increased lavage fluid levels of secretoneurin in seasonal allergic rhinitis.
- 2003
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In: American Journal of Respiratory and Critical Care Medicine. - 1535-4970. ; 167:11, s. 1504-1508
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Journal article (peer-reviewed)abstract
- Secretoneurin is a neuropeptide potentially involved in migration of eosinophils, monocytes, and dendritic cells. Whether secretoneurin is present in the human airway mucosa and whether it is released at ongoing allergic airway inflammation is currently unknown. In patients with allergic rhinitis, we have explored the occurrence of secretoneurin in nasal mucosal biopsies and lavage fluids before and during natural allergen exposure. Immunohistochemical analysis revealed an abundance of nerves displaying secretoneurin immunoreactivity, which were distributed predominantly around blood vessels and submucosal glands. A majority of nerve fibers containing vesicular acetylcholine transporter, tyrosine hydroxylase, calcitonin gene–related peptide, and vasoactive intestinal peptide were also secretoneurin-immunoreactive, indicating a localization of secretoneurin in cholinergic, adrenergic, and sensory nerves. Lavage fluid levels of secretoneurin were increased at allergen exposure (p < 0.01–0.05). Levels of secretoneurin did not correlate with eosinophil cationic protein ({rho} = 0.1, p = 0.7). We conclude that secretoneurin has a widespread occurrence in nasal mucosal nerves of patients with seasonal allergic rhinitis and that increased nasal lavage fluid levels of secretoneurin may characterize ongoing allergen exposure. These data favor a role of secretoneurin in the local traffic of immune cells in human airway mucosa.
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| 3. |
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| 4. |
- Persson, Carl, et al.
(author)
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Airway permeability
- 1995
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In: Clinical and Experimental Allergy. - : Wiley. - 1365-2222. ; 25:9, s. 807-814
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Research review (peer-reviewed)
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| 5. |
- Persson, Carl, et al.
(author)
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Contribution of plasma-derived molecules to mucosal immune defence, disease and repair in the airways
- 1998
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In: Scandinavian Journal of Immunology. - : Wiley. - 1365-3083 .- 0300-9475. ; 47:4, s. 302-313
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Research review (peer-reviewed)abstract
- This review discusses recent observations, in health and disease, on the release and distribution of plasma-derived molecules in the airway mucosa. Briefly, the new data on airway mucosal exudation mechanisms suggest that the protein systems of plasma contribute significantly to the mucosal biology, not only in injured airways but also in such mildly inflamed airways that lack oedema and exhibit no sign of epithelial derangement. Plasma as a source of pluripotent growth factor, adhesive, leucocyte-activating, etc., molecules may deserve a prominent position in schemes that claim to illustrate immunological and inflammatory mechanisms of the airway mucosa in vivo.
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| 6. |
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| 7. |
- Persson, Carl, et al.
(author)
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Plasma-derived proteins in airway defence, disease and repair of epithelial injury
- 1998
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In: European Respiratory Journal. - 1399-3003. ; 11:4, s. 958-970
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Journal article (peer-reviewed)abstract
- One significant characteristic of the airway mucosa in vivo, that cannot easily be mimicked in vitro, is its microcirculation, which generates a highly dynamic, biologically active milieu of plasma-derived molecules that may pass to the airway lumen in vivo. New data on the mechanisms of airway mucosal exudation indicate that the protein systems of circulating plasma may contribute significantly to the biology and immunology of the lamina propria, its surface epithelium and the luminal surface, not only in injured airways, but also in airways that are activated but display no sign of oedema, epithelial disruption, or increased absorption capacity. We suggest that present knowledge of the mechanisms of plasma exudation, together with rapidly emerging information (not detailed herein) on receptors, target cells and cellular responses to the plasma-derived molecules, must be considered in any realistic model that investigates "immuno-inflammatory" mechanisms of the airway mucosa.
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