| 1. |
- Andersson-Sjöland, Annika, et al.
(författare)
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Fibrocytes are a potential source of lung fibroblasts in idiopathic pulmonary fibrosis.
- 2008
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Ingår i: International Journal of Biochemistry & Cell Biology. - : Elsevier BV. - 1878-5875 .- 1357-2725. ; 40, s. 2129-2140
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Tidskriftsartikel (refereegranskat)abstract
- Idiopathic pulmonary fibrosis is characterized by the accumulation of fibroblasts/myofibroblasts and aberrant remodeling of the lung parenchyma. However, the sources of fibroblasts in IPF lungs are unclear. Fibrocytes are circulating progenitors of fibroblasts implicated in wound healing and fibrosis. In this study we evaluated evidence for the presence of fibrocytes in the lung of patients with idiopathic pulmonary fibrosis by immunofluorescence and confocal microscopy. Fibrocytes were identified in tissues in 8 out of 9 fibrotic lungs. Combinations including CXCR4 and a mesenchymal marker stained significantly more fibrocytes/mm(2) of tissue compared with combinations using CD34 or CD45RO with mesenchymal markers: CXCR4/procollagen-I (10.3+/-2.9fibrocytes/mm(2)) and CXCR4/prolyl-4-hydroxylase (4.1+/-3.1), versus CD34/procollagen-I (2.8+/-3.0), CD34/alphaSMA (2.2+/-1.6) and CD45RO/prolyl-4-hydroxylase (1.3+/-1.6); p<0.003. There was a positive correlation between the abundance of fibroblastic foci and the amount of lung fibrocytes (r=0.79; p<0.02). No fibrocytes were identified in normal lungs. The fibrocyte attractant chemokine CXCL12 increased in plasma [median: 2707.5pg/ml (648.1-4884.7) versus 1751.5pg/ml (192.9-2686.0) from healthy controls; p<0.003)] and was detectable in the bronchoalveolar lavage fluid of 40% of the patients but not in controls. In the lung CXCL12 was strongly expressed by alveolar epithelial cells. A negative correlation between plasma levels of CXCL12 with lung diffusing capacity for carbon monoxide (DLCO) (r=-0.56; p<0.03) and oxygen saturation on exercise was found (r=-0.41; p<0.04). These findings indicate that circulating fibrocytes, likely recruited through the CXCR4/CXCL12 axis, may contribute to the expansion of the fibroblast/myofibroblast population in idiopathic pulmonary fibrosis.
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| 2. |
- Andersson Sjöland, Annika, et al.
(författare)
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Fibrocytes are associated with vascular and parenchymal remodelling in patients with obliterative bronchiolitis.
- 2009
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Ingår i: Respiratory Research. - : Springer Science and Business Media LLC. - 1465-9921 .- 1465-993X. ; 10:Oct 30
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The aim of the present study was to explore the occurrence of fibrocytes in tissue and to investigate whether the appearance of fibrocytes may be linked to structural changes of the parenchyme and vasculature in the lungs of patients with obliterative bronchiolitis (OB) following lung or bone marrow transplantation. METHODS: Identification of parenchyme, vasculature, and fibrocytes was done by histological methods in lung tissue from bone marrow or lung-transplanted patients with obliterative bronchiolitis, and from controls. RESULTS: The transplanted patients had significantly higher amounts of tissue in the alveolar parenchyme (46.5 +/- 17.6%) than the controls (21.7 +/- 7.6%) (p < 0.05). The patients also had significantly increased numbers of fibrocytes identified by CXCR4/prolyl4-hydroxylase, CD45R0/prolyl4-hydroxylase, and CD34/prolyl4-hydroxylase compared to the controls (p < 0.01). There was a correlation between the number of fibrocytes and the area of alveolar parenchyma; CXCR4/prolyl 4-hydroxylase (p < 0.01), CD45R0/prolyl 4-hydroxylase (p < 0.05) and CD34/prolyl 4-hydroxylase (p < 0.05). In the pulmonary vessels, there was an increase in the endothelial layer in patients (0.31 +/- 0.13%) relative to the controls (0.037 +/- 0.02%) (p < 0.01). There was a significant correlation between the number of fibrocytes and the total area of the endothelial layer CXCR4/prolyl 4-hydroxylase (p < 0.001), CD45R0/prolyl 4-hydroxylase (p < 0.001) and CD34/prolyl 4-hydroxylase (p < 0.01). The percent areas of the lumen of the vessels were significant (p < 0.001) enlarged in the patient with OB compared to the controls. There was also a correlation between total area of the lumen and number of fibrocytes, CXCR4/prolyl 4-hydroxylase (p < 0.01), CD45R0/prolyl 4-hydroxylase (p < 0.001) and CD34/prolyl 4-hydroxylase (p < 0.01). CONCLUSION: Our results indicate that fibrocytes are associated with pathological remodelling processes in patients with OB and that tissue fibrocytes might be a useful biomarker in these processes.
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| 3. |
- Larsen, Kristoffer, et al.
(författare)
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Antiproliferative heparan sulfate inhibiting hyaluronan and transforming growth factor-β expression in human lung fibroblast cells
- 2005
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Ingår i: Clinical Proteomics. - 1559-0275. ; 1:3-4, s. 271-284
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to examine the effects of heparan sulfate (HS) on factors involved in the remodeling of connective tissue observed in patients with fibrotic respiratory disorders such as asthma. A suitable working model is to stimulate human fetal lung fibroblasts in vitro with structurally different forms of HS. Highly sulfated and iduronic acid (IdoUA)-rich HS specifically decreased cell proliferaton, production of jyaluronan (HA), transforming growth factor (TGF)-β1, and TFF-β-induced α-smooth muscle actin but did not affect the overall proteoglycan production in the cells. These repressed factors are suggested to play a critical role in the early stages of remodeling and myofibroblast activation. Low sulfated and IdoUA-poor HS did not display any effects on these factors. Furthermore, analysis of the protein expression pattern by two-dimensional gel electrophoresis revealed a 70% increased expression of annexin II, which has previously been shown to have a high affinity for both heparin and HS. Heat-shock protein 27 and arsenite translocating factor, both involved in actin organization and polymerization, were also increased in the HS-stimulated cells. Thus, the reduced expression of HA and TGF-β1, both important in the development of fibrosis, seems to be mediated by pecific changes in protein expression of the fibroblast. The observed inhibition of cell proliferation, HA, and TGF-β1 allows speculation of highly sulfated HS as a antifibrotic candidate in the early stage of remodeling.
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| 4. |
- Larsen, Kristoffer, et al.
(författare)
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Functional and phenotypical comparison of myofibroblasts derived from biopsies and bronchoalveolar lavage in mild asthma and scleroderma
- 2006
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Ingår i: Respiratory Research. - : Springer Science and Business Media LLC. - 1465-9921 .- 1465-993X. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Background: Activated fibroblasts, which have previously been obtained from bronchoalveolar lavage fluid (BALF), are proposed to be important cells in the fibrotic processes of asthma and scleroderma (SSc). We have studied the motility for BALF derived fibroblasts in patients with SSc that may explain the presence of these cells in the airway lumen. Furthermore, we have compared phenotypic alterations in activated fibroblasts from BALF and bronchial biopsies from patients with mild asthma and SSc that may account for the distinct fibrotic responses. Methods: Fibroblasts were cultured from BALF and bronchial biopsies from patients with mild asthma and SSc. The motility was studied using a cell migration assay. Western Blotting was used to study the expression of alpha-smooth muscle actin (alpha-SMA), ED-A fibronectin, and serine arginine splicing factor 20 (SRp20). The protein expression pattern was analyzed to reveal potential biomarkers using two-dimensional electrophoresis (2-DE) and sequencing dual matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-TOF). The Mann-Whitney method was used to calculate statistical significance. Results: Increased migration and levels of ED-A fibronectin were observed in BALF fibroblasts from both groups of patients, supported by increased expression of RhoA, Rac1, and the splicing factor SRp20. However, these observations were exclusively accompanied by increased expression of alpha-SMA in patients with mild asthma. Compared to BALF fibroblasts in mild asthma, fibroblasts in SSc displayed a differential protein expression pattern of cytoskeletal- and scavenger proteins. These identified proteins facilitate cell migration, oxidative stress, and the excessive deposition of extracellular matrix observed in patients with SSc. Conclusion: This study demonstrates a possible origin for fibroblasts in the airway lumen in patients with SSc and important differences between fibroblast phenotypes in mild asthma and SSc. The findings may explain the distinct fibrotic processes and highlight the motile BALF fibroblast as a potential target cell in these disorders.
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| 5. |
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| 6. |
- Malmström, Erik, et al.
(författare)
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The importance of fibroblasts in remodelling of the human uterine cervix during pregnancy and parturition.
- 2007
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Ingår i: Molecular Human Reproduction. - : Oxford University Press (OUP). - 1460-2407. ; 13, s. 333-341
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Tidskriftsartikel (refereegranskat)abstract
- It is well established that fibroblasts play a crucial role in pathophysiological extracellular matrix remodelling. The aim of this project is to elucidate their role in normal physiological remodelling. Specifically, the remodelling of the human cervix during pregnancy, resulting in an enabled passage of the child, is used as the model system. Fibroblast cultures were established from cervices of non-pregnant women, women after 36 weeks of pregnancy and women directly after partus. The cells were immunostained and quantified by western blots for differentiation markers. The cultures were screened for cytokine and metalloproteinase production and characterized by global proteome analysis. The cell cultures established from partal donors differ significantly from those from non-pregnant donors, which is in accordance with in vivo findings. A decrease in alpha-smooth actin and prolyl-4hydroxylase and an increase in interleukin (IL)-6, IL-8 and matrix metalloproteinases (MMP)-1 and MMP-3 were observed in cultures from partal donors. 2D-gel electrophoresis followed by mass spectrometry showed that the expression of 59 proteins was changed significantly in cultures of partal donors. The regulated proteins are involved in protein kinase C signalling, Ca2+ binding, cytoskeletal organization, angiogenesis and degradation. Our data suggest that remodelling of the human cervix is orchestrated by fibroblasts, which are activated or recruited by the inflammatory processes occurring during the ripening cascade.
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| 7. |
- Malmström, Johan, et al.
(författare)
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Quantitative proteomic analysis of fibroblast nuclear proteins after stimulation with mitogen activated protein kinase inhibiting heparan sulfate
- 2005
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Ingår i: Journal of Chromatography. B. - : Elsevier BV. - 1873-376X .- 1570-0232. ; 815:1-2, s. 333-342
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Tidskriftsartikel (refereegranskat)abstract
- Certain structures of heparan sulfate (HS) inhibit cell proliferation of fibroblasts. Whether this inhibition is dependent on inhibition of mitogenic signaling pathways or nuclear translocation of HS is unknown. In this study we investigated possible mechanism(s) and structural requirements by which antiproliferative glycosaminoglycans exert their effects on mitogen-activated protein kinase (MAP kinase) phosphorylation, a key intermediate in cell signaling, followed by quantitative proteomic analysis of nuclear proteins by stable isotope coded affinity tags, multidimensional chromatography and tandem mass spectrometry. Serum starved human lung fibroblasts were stimulated with serum, platelet derived growth factor (PDGF-BB) or epidermal growth factor (EGF) in the presence of structurally different glycosaminoglycans. Antiproliferative heparan sulfate with a high content of 2-O-sulfated iduronic acid (IdoA-2SO4) and heavily sulfated glucosamine, and the structurally related glycosaminoglycan heparin inhibited significantly serum stimulated MAP kinase phosphorylation, by at least 80% when stimulated by serum and HS6. We hypothesized that the inhibition of the MAP kinase pathway will have effect in the nuclear proteome. Therefore an isotope coded affinity tag (ICAT) reagent labeling of nuclear proteins and tandem mass spectrometry was applied, resulting in the identification and quantification of 206 proteins. Several nuclear proteins were found to be induced or repressed due to HS stimulation, where the repression EBNA-2 co-activator and the induction of PML protein were of special interest. These results show that heparan sulfate with high content of (IdoA-2SO4) and heavily sulfated glucosamine specifically inhibits MAP kinase activation with a subsequent change in the nuclear proteome of the fibroblast.
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| 8. |
- Malmström, Lars, et al.
(författare)
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2DDB – a bioinformatics solution for analysis of quantitative proteomics data
- 2006
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Ingår i: BMC Bioinformatics. - : Springer Science and Business Media LLC. - 1471-2105. ; 7:158
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Tidskriftsartikel (refereegranskat)abstract
- Background We present 2DDB, a bioinformatics solution for storage, integration and analysis of quantitative proteomics data. As the data complexity and the rate with which it is produced increases in the proteomics field, the need for flexible analysis software increases. Results 2DDB is based on a core data model describing fundamentals such as experiment description and identified proteins. The extended data models are built on top of the core data model to capture more specific aspects of the data. A number of public databases and bioinformatical tools have been integrated giving the user access to large amounts of relevant data. A statistical and graphical package, R, is used for statistical and graphical analysis. The current implementation handles quantitative data from 2D gel electrophoresis and multidimensional liquid chromatography/mass spectrometry experiments. Conclusion The software has successfully been employed in a number of projects ranging from quantitative liquid-chromatography-mass spectrometry based analysis of transforming growth factor-beta stimulated fi-broblasts to 2D gel electrophoresis/mass spectrometry analysis of biopsies from human cervix. The software is available for download at SourceForge.
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| 9. |
- Meinert, M, et al.
(författare)
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Labour induces increased concentrations of biglycan and hyaluronan in human fetal membranes
- 2007
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Ingår i: Placenta. - London : Saunders Elsevier. - 0143-4004 .- 1532-3102. ; 28:5-6, s. 482-486
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The proteoglycan decorin stabilizes collagen whereas biglycan and hyaluronan disrupt well-organized collagen. The aim was to compare hyaluronan and proteoglycans in human fetal membranes obtained before and after spontaneous labour at term.Study design: Prelabour samples of fetal membranes (N = 9) were obtained from elective caesarean sections and regionally sampled from over the cervix (cervical membranes) and mid-zone samples between this area and the placental edge. Postlabour samples (N = 11) were obtained from spontaneous vaginal delivery and also regionally sampled. Amnion and chorio-decidua were analysed separately. The proteoglycans decorin and biglycan were analysed using alcian blue precipitation, SDS polyacrylamide gel electrophoresis and immunostaining. Hyaluronan was analysed using a radioimmunoassay and by histochemistry. Collagen was measured by estimating hydroxyproline content.Results: In prelabour membranes the biglycan concentration (mu g/mg wtw) in the cervical amnion was 40% lower than in the mid-zone amnion (P < 0.05). After delivery the cervical amnion showed a twofold increase in biglycan (P < 0.05), a 30% decrease in collagen (P < 0.05), and a 50% decrease in decorin concentration (P < 0.05). In mid-zone samples after delivery the concentrations of hyaluronan showed an increase form 1.0 to 4.9 mu g/mg wtw (P < 0.05). Histology demonstrated a gelatinous substance, which separated amnion and chorio-decidua, in particular at the cervical site. This gelatinous substance contained hyaluronan at a concentration of 3.0 mu g/mg wtw.Conclusion: It is well established that prelabour fetal membranes are considerably stronger than postlabour fetal membranes. Two features may explain this; a weakening of the amnion combined with a separation of amnion and chorio-decidua. The biomechanical changes are consistent with the decrease in collagen and decorin, and the increase in hyaluronan and biglycan demonstrated in this study. The separation of the membranes is caused by the formation of a gelatinous substance, rich in hyaluronan. The results indicate that the biomechanical changes are not merely secondary to the stress of labour but that an active maturation process is involved.
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| 10. |
- Nihlberg, Kristian, et al.
(författare)
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Tissue fibrocytes in patients with mild asthma: A possible link to thickness of reticular basement membrane?
- 2006
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Ingår i: Respiratory Research. - : Springer Science and Business Media LLC. - 1465-9921 .- 1465-993X. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Background: Myofibroblasts, proposed as being derived from circulating fibrocytes, are considered to be important cells in thickening of the basement membrane in patients with asthma. We have studied the correlation of tissue fibrocyte levels to basement membrane thickness and the presence of fibrocytes in bronchoalveolar lavage fluid (BALF) in steroid-naive patients with mild asthma and controls. Methods: Patients with mild asthma (n=9) were recruited and divided into two categories based on whether or not fibroblast-like cells could be established from BALF. Non-asthmatic healthy subjects (n=5) were used as controls. Colocalization of the fibrocyte markers CD34, CD45RO, procollagen I, and alpha-smooth muscle actin (alpha-SMA) were identified in bronchial biopsies from patients and controls by confocal microscopy. Kruskall-Wallis method was used to calculate statistical significance and Spearman coefficient of rank correlation was used to assess the degree of association. Results: In patients with BALF fibroblasts, a 14-fold increase of tissue cells expressing CD34/CD45RO/alpha-SMA and a 16-fold increase of tissue cells expressing CD34/procollagen I was observed when compared to controls (p<0.05). In contrast, patients without BALF fibroblasts displayed a 2-fold increase when compared to controls (p<0.05). Fibrocytes were localized close to the basement membrane which was significantly thicker in patients with BALF fibroblasts when compared to the other two groups of subjects. Furthermore, basement membrane thickness could be correlated to the number of fibrocytes in tissue (r=0.711). Fibroblasts-like cells were cultured from BALF where 17.6% of these cells expressed CD34, CD45RO and alpha-SMA. Conclusion: These findings indicate a correlation between recruited fibrocytes in tissue and thickness of basement membrane. Fibroblast progenitor cells may therefore be important in airway remodeling in steroid-naive patients with mild asthma.
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