| 1. |
- Andersson, Cecilia K, et al.
(författare)
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Activated MCTC mast cells infiltrate diseased lung areas in cystic fibrosis and idiopathic pulmonary fibrosis
- 2011
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Ingår i: Respiratory Research. - : Springer Science and Business Media LLC. - 1465-9921 .- 1465-993X. ; 12:139
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Tidskriftsartikel (refereegranskat)abstract
- Background: Although mast cells are regarded as important regulators of inflammation and tissue remodelling, their role in cystic fibrosis (CF) and idiopathic pulmonary fibrosis (IPF) has remained less studied. This study investigates the densities and phenotypes of mast cell populations in multiple lung compartments from patients with CF, IPF and never smoking controls. Methods: Small airways, pulmonary vessels, and lung parenchyma were subjected to detailed immunohistochemical analyses using lungs from patients with CF (20 lung regions; 5 patients), IPF (21 regions; 7 patients) and controls (16 regions; 8 subjects). In each compartment the densities and distribution of MCT and MCTC mast cell populations were studied as well as the mast cell expression of IL-6 and TGF-beta. Results: In the alveolar parenchyma in lungs from patients with CF, MCTC numbers increased in areas showing cellular inflammation or fibrosis compared to controls. Apart from an altered balance between MCTC and MCT cells, mast cell in CF lungs showed elevated expression of IL-6. In CF, a decrease in total mast cell numbers was observed in small airways and pulmonary vessels. In patients with IPF, a significantly elevated MCTC density was present in fibrotic areas of the alveolar parenchyma with increased mast cell expression of TGF-beta. The total mast cell density was unchanged in small airways and decreased in pulmonary vessels in IPF. Both the density, as well as the percentage, of MCTC correlated positively with the degree of fibrosis. The increased density of MCTC, as well as MCTC expression of TGF-beta, correlated negatively with patient lung function. Conclusions: The present study reveals that altered mast cell populations, with increased numbers of MCTC in diseased alveolar parenchyma, represents a significant component of the histopathology in CF and IPF. The mast cell alterations correlated to the degree of tissue remodelling and to lung function parameters. Further investigations of mast cells in these diseases may open for new therapeutic strategies.
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| 2. |
- Andersson, Cecilia K, et al.
(författare)
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Alterations in Lung Mast Cell Populations in Patients with COPD.
- 2010
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Ingår i: American Journal of Respiratory and Critical Care Medicine. - 1535-4970. ; 181:3, s. 206-217
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Tidskriftsartikel (refereegranskat)abstract
- RATIONALE: Mast cells have important roles in innate immunity and tissue remodeling but have remained poorly studied in inflammatory airway diseases like COPD. OBJECTIVES: To perform a detailed histological characterization of human lung mast cell popu-lations at different severities of COPD, comparing with smoking and never-smoking controls. METHODS: Mast cells were analyzed in lung tissues from patients with mild to very severe COPD, GOLD IâIV (n = 25, 10 of whom were treated with corticosteroids). Never-smokers and smokers served as controls. The density, morphology and molecular characteristics of mucosal and connective tissue mast cells (MCT and MCTC, respectively) were analyzed in several lung regions. MEASUREMENTS AND MAIN RESULTS: In all compartments of COPD lungs, especially at severe stages, the MCTC population increased in density while the MCT population decreased. The net result was a reduction in total mast cell density. This phenomenon was paralleled by in-creased numbers of luminal mast cells whereas the numbers of TUNEL(+) apoptotic mast cells remained unchanged. In COPD lungs, the MCT and MCTC populations showed alterations in morphology and expression of CD88 (C5a-R), TGF-beta, and renin. Statistically significant cor-relations were found between several COPD-related mast cell alterations and lung function parameters. CONCLUSIONS: As COPD progresses to its severe stages, the mast cell population in the lung undergoes changes in density, distribution, and molecular expression. In COPD lungs, these novel histopathological features were found to be correlated to lung function and they may thus have clinical consequences.
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| 3. |
- Andersson, Cecilia K, et al.
(författare)
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Novel Site-Specific Mast Cell Subpopulations in the Human Lung.
- 2009
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Ingår i: Thorax. - : BMJ. - 1468-3296 .- 0040-6376. ; 64, s. 297-305
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Lung mast cells are stereotypically divided into connective tissue (MCTC) and mucosal (MCT) mast cells. This study tests the hypothesis that each of these subtypes can be divided further into site-specific populations created by the microenvironment within each anatomic lung compartment. METHODS: To study mast cells under non-inflamed conditions surgical resections and bronchial and transbronchial biopsies from non-smoking individuals were obtained to investigate morphometric and molecular characteristics of mast cell populations in multiple lung structures by immunohistochemistry and electron microscopy. RESULTS: MCT and MCTC coexisted at all compartments with MCT being the prevailing type in bronchi, bronchioles and the alveolar parenchyma. MCTC were more abundant in pulmonary vessels and the pleura. Each of the MCTC and MCT phenotypes could be further differentiated into site-specific populations. MCTC was of significantly larger size in pulmonary vessels than in small airway walls (p<0.001) while a reversed pattern was observed for MCT (p<0.001). Within each MCTC and MCT population there was also distinct site-specific expression pattern of the IgE-receptor, IL-9 receptor, renin, histidine decarboxylase, VEGF, FGF, 5-Lipoxygense, and LTC4-synthase; e.g. bronchial MCT consistently expressed more histidine decarboxylase than alveolar MCT (p<0.004). Renin content was high among vascular MCTC but markedly reduced among MCTC in other compartments (p<0.0002). Notably, for both MCTC and MCT IgE-receptor was highly expressed in conducting airways but virtually absent in alveolar parenchyma. CONCLUSION: Our findings demonstrate novel site-specific sub-populations of lung MCTC and MCT. This observation is suggested to have important implications in unravelling the recently proposed role of mast cells in a variety of pulmonary diseases.
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| 4. |
- Hallgren, Oskar, et al.
(författare)
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Altered fibroblast proteoglycan production in COPD
- 2010
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Ingår i: Respiratory Research. - : Springer Science and Business Media LLC. - 1465-9921 .- 1465-993X. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Background: Airway remodeling in COPD includes reorganization of the extracellular matrix. Proteoglycans play a crucial role in this process as regulators of the integrity of the extracellular matrix. Altered proteoglycan immunostaining has been demonstrated in COPD lungs and this has been suggested to contribute to the pathogenesis. The major cell type responsible for production and maintenance of ECM constituents, such as proteoglycans, are fibroblasts. Interestingly, it has been proposed that central airways and alveolar lung parenchyma contain distinct fibroblast populations. This study explores the hypothesis that altered depositions of proteoglycans in COPD lungs, and in particular versican and perlecan, is a result of dysregulated fibroblast proteoglycan production. Methods: Proliferation, proteoglycan production and the response to TGF-beta(1) were examined in vitro in centrally and distally derived fibroblasts isolated from COPD patients (GOLD stage IV) and from control subjects. Results: Phenotypically different fibroblast populations were identified in central airways and in the lung parenchyma. Versican production was higher in distal fibroblasts from COPD patients than from control subjects (p < 0.01). In addition, perlecan production was lower in centrally derived fibroblasts from COPD patients than from control subjects (p < 0.01). TGF-beta(1) triggered similar increases in proteoglycan production in distally derived fibroblasts from COPD patients and control subjects. In contrast, centrally derived fibroblasts from COPD patients were less responsive to TGF-beta(1) than those from control subjects. Conclusions: The results show that fibroblasts from COPD patients have alterations in proteoglycan production that may contribute to disease development. Distally derived fibroblasts from COPD patients have enhanced production of versican that may have a negative influence on the elastic recoil. In addition, a lower perlecan production in centrally derived fibroblasts from COPD patients may indicate alterations in bronchial basement membrane integrity in severe COPD.
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| 5. |
- Hallgren, Oskar, et al.
(författare)
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Enhanced ROCK1 dependent contractility in fibroblast from chronic obstructive pulmonary disease patients
- 2012
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Ingår i: Journal of Translational Medicine. - : Springer Science and Business Media LLC. - 1479-5876. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Background: During wound healing processes fibroblasts account for wound closure by adopting a contractile phenotype. One disease manifestation of COPD is emphysema which is characterized by destruction of alveolar walls and our hypothesis is that fibroblasts in the COPD lungs differentiate into a more contractile phenotype as a response to the deteriorating environment. Methods: Bronchial (central) and parenchymal (distal) fibroblasts were isolated from lung explants from COPD patients (n = 9) (GOLD stage IV) and from biopsies from control subjects and from donor lungs (n = 12). Tissue-derived fibroblasts were assessed for expression of proteins involved in fibroblast contraction by western blotting whereas contraction capacity was measured in three-dimensional collagen gels. Results: The basal expression of rho-associated coiled-coil protein kinase 1 (ROCK1) was increased in both centrally and distally derived fibroblasts from COPD patients compared to fibroblasts from control subjects (p < 0.001) and (p < 0.01), respectively. Distally derived fibroblasts from COPD patients had increased contractile capacity compared to control fibroblasts (p < 0.01). The contraction was dependent on ROCK1 activity as the ROCK inhibitor Y27632 dose-dependently blocked contraction in fibroblasts from COPD patients. ROCK1-positive fibroblasts were also identified by immunohistochemistry in the alveolar parenchyma in lung tissue sections from COPD patients. Conclusions: Distally derived fibroblasts from COPD patients have an enhanced contractile phenotype that is dependent on ROCK1 activity. This feature may be of importance for the elastic dynamics of small airways and the parenchyma in late stages of COPD.
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| 6. |
- Mori, Michiko, et al.
(författare)
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Appearance of remodelled and dendritic cell-rich alveolar-lymphoid interfaces provides a structural basis for increased alveolar antigen uptake in chronic obstructive pulmonary disease
- 2013
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Ingår i: Thorax. - : BMJ. - 0040-6376 .- 1468-3296. ; 68:6, s. 521-531
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Tidskriftsartikel (refereegranskat)abstract
- Rationale The alveolar pathology in chronic obstructive pulmonary disease (COPD) involves antigen-driven immune events. However, the induction sites of alveolar adaptive immune responses have remained poorly investigated. Objectives To explore the hypothesis that interfaces between the alveolar lumen and lymphoid aggregates (LAs) provide a structural basis for increased alveolar antigen uptake in COPD lungs. Methods Lung samples from patients with mild (Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage I), moderate–severe (GOLD II–III), and very severe (GOLD IV) COPD were subjected to detailed histological assessments of adaptive immune system components. Never smokers and smokers without COPD served as controls. Results Quantitative histology, involving computerised three-dimensional reconstructions, confirmed a rich occurrence of alveolar-restricted LAs and revealed, for the first time, that the vast majority of vascular or bronchiolar associated LAs had alveolar interfaces but also an intricate network of lymphatic vessels. Uniquely to COPD lungs, the interface epithelium had transformed into a columnar phenotype. Accumulation of langerin (CD207)+ dendritic cells occurred in the interface epithelium in patients with COPD but not controls. The antigen-capturing capacity of langerin+ dendritic cells was confirmed by increased alveolar protrusions and physical T cell contact. Several of these immune remodelling parameters correlated with lung function parameters. Conclusions Severe stages of COPD are associated with an emergence of remodelled and dendritic cell-rich alveolar–lymphoid interfaces. This novel type of immune remodelling, which predicts an increased capacity to respond to alveolar antigens, is suggested to contribute to aggravated inflammation in COPD.
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| 7. |
- Mori, Michiko, et al.
(författare)
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Increased number and altered phenotype of lymphatic vessels in peripheral lung compartments of patients with COPD
- 2013
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Ingår i: Respiratory Research. - : Springer Science and Business Media LLC. - 1465-9921 .- 1465-993X. ; 14
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Tidskriftsartikel (refereegranskat)abstract
- Background: De novo lymphatic vessel formation has recently been observed in lungs of patients with moderate chronic obstructive pulmonary disease (COPD). However, the distribution of lymphatic vessel changes among the anatomical compartments of diseased lungs is unknown. Furthermore, information regarding the nature of lymphatic vessel alterations across different stages of COPD is missing. This study performs a detailed morphometric characterization of lymphatic vessels in major peripheral lung compartments of patients with different severities of COPD and investigates the lymphatic expression of molecules involved in immune cell trafficking. Methods: Peripheral lung resection samples obtained from patients with mild (GOLD stage I), moderate-severe (GOLD stage II-III), and very severe (GOLD stage IV) COPD were investigated for podoplanin-immunopositive lymphatic vessels in distinct peripheral lung compartments: bronchioles, pulmonary blood vessels and alveolar walls. Control subjects with normal lung function were divided into never smokers and smokers. Lymphatics were analysed by multiple morphological parameters, as well as for their expression of CCL21 and the chemokine scavenger receptor D6. Results: The number of lymphatics increased by 133% in the alveolar parenchyma in patients with advanced COPD compared with never-smoking controls (p < 0.05). In patchy fibrotic lesions the number of alveolar lymphatics increased 20-fold from non-fibrotic parenchyma in the same COPD patients. The absolute number of lymphatics per bronchiole and artery was increased in advanced COPD, but numbers were not different after normalization to tissue area. Increased numbers of CCL21- and D6-positive lymphatics were observed in the alveolar parenchyma in advanced COPD compared with controls (p < 0.01). Lymphatic vessels also displayed increased mean levels of immunoreactivity for CCL21 in the wall of bronchioles (p < 0.01) and bronchiole-associated arteries (p < 0.05), as well as the alveolar parenchyma (p < 0.001) in patients with advanced COPD compared with never-smoking controls. A similar increase in lymphatic D6 immunoreactivity was observed in bronchioles (p < 0.05) and alveolar parenchyma (p < 0.01). Conclusions: This study shows that severe stages of COPD is associated with increased numbers of alveolar lymphatic vessels and a change in lymphatic vessel phenotype in major peripheral lung compartments. This novel histopathological feature is suggested to have important implications for distal lung immune cell traffic in advanced COPD.
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