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- Ghafouri, Bijar, et al.
(author)
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Newly identified proteins in human nasal lavage fluid from non-smokers and smokers using two-dimensional gel electrophoresis and peptide mass fingerprinting
- 2002
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In: Proteomics. - 1615-9853 .- 1615-9861. ; 2:1, s. 112-120
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Journal article (peer-reviewed)abstract
- Human nasal lavage fluids (NLFs) were analyzed with two-dimensional gel electrophoresis (2-DE) and proteins were identified with peptide mass fingerprinting using matrix-assisted laser desoption/ionization time of flight mass spectrometry. In some cases, the identification was verified by analysis of post-source decay fragmentation spectra. Many of the identified proteins were new forms or fragments of previously found proteins (e.g. albumin, lactoferrin, cystatin, calgranulin, von Ebners gland protein and palate lung nasal epithelium clone), while others were proteins that have previously been indicated by 2-DE image matching or immunoblots (e.g. apolipoprotein AI, lysozyme C, and Clara cell secretory protein). Some new proteins, not shown before in 2-DE patterns of NLF were also found, e.g. mammaglobin B, 2-microglobulin and immunoglobulin J chain. Of the identified NLF proteins many appear to be involved in inflammatory and immune responses. A study was therefore conducted to investigate if the levels of these proteins were changed in smokers compared to nonsmokers. It was found that NLF from smokers contained decreased levels of Clara cell secretory protein, and increased proportions of a truncated variant of lipocortin-1, three acidic forms of α1-antitrypsin, and one phosphorylated form of cystatin S. Furthermore, NLF from smokers contained increased proportions of a new variant of palate lung nasal epithelium clone (PLUNC), a recently identified airway irritation marker. The results demonstrate that 2-DE of NLF may be used to assess alterations of proteins or post-translationally modified proteins in smokers. Clara cell secretory protein (CC 16, CC 10) and lipocortin-1 are two anti-inflammatory, phospholipase A2 inhibitory proteins, and α1-antitrypsin and cystatin S are two proteinase inhibitors. Changed levels of these proteins may therefore be of importance to the airway inflammation caused by smoking. The results also support the notion that PLUNC is involved in inflammatory responses in the upper airways.
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- Lindbom, John, 1960-, et al.
(author)
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Increased gene expression of novel cytosolic and secretory phospholipase A2 types in human airway epithelial cells induced by tumor necrosis factor-α and IFN-γ
- 2002
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In: Journal of Interferon and Cytokine Research. - : Mary Ann Liebert Inc. - 1079-9907 .- 1557-7465. ; 22:9, s. 947-955
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Journal article (peer-reviewed)abstract
- Phospholipase A2 (PLA2) is a growing family of enzymes that may play a major role in inflammation. We investigated the effect of tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) on the gene expression of 19 different PLA2 types (IB, IIA, IID, IIE, IIF, III, IVA, IVB, IVC, V, VIA, VIB, VIIA, VIIB, VIIIA, VIIIB, X, XII, and XIII) in human bronchoepithelial (BEAS-2B) and nasal epithelial (RPMI 2650) cells. The cells were stimulated with TNF-α or IFN-γ for different lengths of time (1, 4, 18, and 48 h), and the mRNA levels of the different PLA2 types were determined by reverse transcriptase-PCR (RT-PCR) and normalized to those of the housekeeping gene, GAPDH. In both cell lines, TNF-α increased the expression of PLA2 IVA and IVC, and IFN-γ increased the expression of PLA2 IIA and IID. No influence on the gene expression of PLA2-activating protein (PLAP) was noted on cytokine stimulation. These findings indicate that TNF-α and IFN-γ induce gene expression of two novel cytosolic and secretory PLA2 types (IVC and IID, respectively) in human airway epithelial cells. The possibility that these PLA2 types are involved in cytokine-mediated inflammation in the respiratory tract is inferred.
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- Söderholm, Johan D, 1958-, et al.
(author)
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Augmented increase in tight junction permeability by luminal stimuli in the non-inflamed ileum of crohn's disease
- 2002
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In: Gut. - : BMJ. - 0017-5749 .- 1468-3288. ; 50:3, s. 307-313
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Journal article (peer-reviewed)abstract
- Background: Crohn's disease is associated with deranged intestinal permeability in vivo, suggesting dysfunction of tight junctions. The luminal contents are important for development of neoinflammation following resection. Regulation of tight junctions by luminal factors has not previously been studied in Crohn's disease. Aims: The aim of the study was to investigate the effects of a luminal stimulus, known to affect tight junctions, on the distal ileum in patients with Crohn's disease. Patients: Surgical specimens from the distal ileum of patients with Crohn's disease (n=l 2) were studied, and ileal specimens from colon cancer patients (n=l 3) served as controls. Methods: Mucosal permeability to 51Cr-EDTA and electrical resistance were studied in Ussing chambers during luminal exposure to sodium caprate (a constituent of milk fat, affecting tight junctions) or to buffer only. The mechanisms involved were studied by mucosal ATP levels, and by electron and confocal microscopy. Results: Baseline permeability was the same in non-inflamed ileum of Crohn's disease and controls. Sodium caprate induced a rapid increase in paracellular permeability - that is, increased permeation of 51Cr-EDTA and decreased electrical resistance - which was more pronounced in non-inflamed ileum of Crohn's disease, and electron microscopy showed dilatations within the tight junctions. Moreover, sodium caprate induced disassembly of perijunctional filamentous actin was more pronounced in Crohn's disease mucosa. Mucosal permeability changes were accompanied by mitochondrial swelling and a fall in epithelial ATP content, suggesting uncoupling of oxidative phosphorylation. Conclusions: The tight junctions in the non-inflamed distal ileum of Crohn's disease were more reactive to luminal stimuli, possibly mediated via disturbed cytoskeletal contractility. This could contribute to the development of mucosal neoinflammation in Crohn's disease.
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