| 1. |
- Blanco, Ignacio, et al.
(författare)
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Estimates of the prevalence and number of Fibromyalgia syndrome patients and their alpha-1 antitrypsin phenotypic distribution in ten countries
- 2007
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Ingår i: Journal of Musculoskeletal Pain. - 1540-7012. ; 15:4, s. 41540-41540
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Forskningsöversikt (refereegranskat)abstract
- Objectives: During the last few years, clinical, epidemiological, and pathological evidence has suggested that inherited alpha-1 antitrypsin [AAT] deficiency might play a role in the development of the fibromyalgia syndrome [FMS], probably because of the loss of AAT anti-inflammatory efficacy. The objective of this study was to estimate the prevalence and number of FMS patients, and their AAT phenotypic distribution worldwide. Methods: A critical review selecting reliable studies on the subject. Results: Studies on AAT gene frequencies and FMS prevalence were retrieved for ten countries worldwide, namely Canada, the United States of America [USA], Denmark, Finland, Germany, Italy, the Netherlands, Spain, Sweden, and Pakistan. The severe deficiency Z allele was found in all these countries, with very high frequencies in Denmark and Sweden [23 and 27 per 1,000, respectively], high frequencies in Italy and Spain [16 and 17], intermediate frequencies in Germany, the Netherlands, Canada, and the USA [10 to 14], and a low frequency in Pakistan [nine per 1,000]. The calculated prevalence of AAT deficiency and the number of FMS patients with AAT deficiency were 1/10 and 25,408 in Canada, 1/11 and 478,681 in the US, 1/9 and 3,124 in Denmark, 1/36 and 726 in Finland, 1/16 and 48,523 in Germany, 1/13 and 84,876 in Italy, 1115 and 9,639 in the Netherlands, 1/4 and 114,359 in Spain, 1/11 and 9,065 in Sweden, and 1/25 and 85.965 in Pakistan. Our calculations predict that AAT deficiency would remain undetected in around nine percent of FMS patients, with about eight percent of them carrying moderate deficiency phenotypes [MS, SS, and MZ], and less than one percent with severe deficiency phenotypes [SZ and ZZ]. Conclusions: Therefore, AAT phenotype characterization should be recommended in FMS patients and the possible efficacy of AAT replacement therapy in severe deficiency FMS patients should warrant further Studies.
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| 2. |
- Blanco, Ignacio, et al.
(författare)
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Low plasma levels of monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-alpha (TNF alpha), and vascular endothelial growth factor (VEGF) in patients with alpha1-antitrypsin deficiency-related fibromyalgia
- 2010
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Ingår i: Clinical Rheumatology. - : Springer Science and Business Media LLC. - 1434-9949 .- 0770-3198. ; 29:2, s. 189-197
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Tidskriftsartikel (refereegranskat)abstract
- Abnormalities in blood inflammatory markers have been associated with clinical manifestations and the pathogenesis of the fibromyalgia syndrome (FMS); a relationship between inherited alpha1-antitrypsin deficiency (AATD) and FMS has also been recently raised. In this study, plasma levels of inflammatory markers in FMS patients with and without AATD have been investigated. Blood samples from 138 age-matched females (79 FMS) and 59 general population (GP), with normal MM [n = 82 (59.4%)] and with MS, MZ, SZ, and ZZ AATD genotypes [n = 56 (40.6%)], were analyzed by ELISA for monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-alpha (TNF alpha), soluble TNF alpha receptors I and II, interleukin-8, and vascular endothelial growth factor (VEGF). Plasma levels of MCP-1, VEGF, and TNF alpha were significantly lower in FMS and GP subjects with AATD compared with those with normal MM-AAT genotypes. Moreover, plasma levels of MCP-1, VEGF, and TNF alpha were lower in AATD subjects with FMS than in those without FMS (P = 0.000, 0.000, and 0.046, respectively). No statistical differences were found for the other substances measured. Furthermore, a logistic regression model based on plasma MCP-1 cutoff value of a parts per thousand currency sign130 pg/ml allowed us to discriminate between FMS and GP subjects with a sensitivity of about 93% and a specificity of 79%. Low plasma levels of MCP-1, VEGF, and TNF alpha are related to AATD, although more markedly in FMS patients. Thus, hypotheses considering FMS as an inflammatory condition related to high plasma levels of inflammatory biomarkers cannot be supported.
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| 3. |
- Hadzic, Radinka, et al.
(författare)
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alpha1-Antitrypsin inhibits Moraxella catarrhalis MID protein-induced tonsillar B cell proliferation and IL-6 release.
- 2006
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Ingår i: Immunology Letters. - : Elsevier BV. - 0165-2478 .- 1879-0542. ; 102:2, s. 141-147
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Tidskriftsartikel (refereegranskat)abstract
- alpha 1-Antitrypsin (AAT) is a major circulating and tissues inhibitor of serine proteinases implicated in the regulation of inflammation and host defence. There is now increasing evidence that AAT may also exhibit anti-inflammatory activities independent of its protease inhibitor function. This study was undertaken to investigate the effects of native (inhibitory) and polymerized (non-inhibitory) forms of AAT on MID (Moraxella IgD binding protein)-induced human tonsillar B cell activation in vitro. We found that 0.5 mu g/ml MID induces B cell proliferation and stimulates IL-6 release (p < 0.001) relative to non-stimulated controls. Both native and polymerized AAT (0.5 mg/ml) inhibited MID-stimulated B cell proliferation in a similar manner (by 70%, p < 0.001), whereas MID-induced IL-6 release was more strongly suppressed by polymefized (9.9-fold, p < 0.001) as compared to native AAT (2.8-fold, p < 0.01). Electrophoretic analysis of cell culture media did not indicate any interaction between AAT and MID, and flow cytometry data showed no competition for the same receptor. The effects of AATs were observed whether added together with MID or 2 h after MID-addition to cell cultures. Thus, our data demonstrate that AAT inhibits MID-induced B cell activation in vitro that is unrelated to its protease inhibitory activity and is not dependent on MID binding to the cell surface.
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| 4. |
- Hadzic, Radinka, et al.
(författare)
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α1-Antitrypsin inhibits Moraxella catarrhalis MID protein-induced tonsillar B cell proliferation and IL-6 release
- 2006
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Ingår i: Immunology Letters. - 0165-2478 .- 1879-0542. ; 102:2, s. 141-147
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Tidskriftsartikel (refereegranskat)abstract
- α1-Antitrypsin (AAT) is a major circulating and tissues inhibitor of serine proteinases implicated in the regulation of inflammation and host defence. There is now increasing evidence that AAT may also exhibit anti-inflammatory activities independent of its protease inhibitor function. This study was undertaken to investigate the effects of native (inhibitory) and polymerized (non-inhibitory) forms of AAT on MID (Moraxella IgD binding protein)-induced human tonsillar B cell activation in vitro. We found that 0.5 μg/ml MID induces B cell proliferation and stimulates IL-6 release (p < 0.001) relative to non-stimulated controls. Both native and polymerized AAT (0.5 mg/ml) inhibited MID-stimulated B cell proliferation in a similar manner (by 70%, p < 0.001), whereas MID-induced IL-6 release was more strongly suppressed by polymerized (9.9-fold, p < 0.001) as compared to native AAT (2.8-fold, p < 0.01). Electrophoretic analysis of cell culture media did not indicate any interaction between AAT and MID, and flow cytometry data showed no competition for the same receptor. The effects of AATs were observed whether added together with MID or 2 h after MID-addition to cell cultures. Thus, our data demonstrate that AAT inhibits MID-induced B cell activation in vitro that is unrelated to its protease inhibitory activity and is not dependent on MID binding to the cell surface.
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| 5. |
- Janciauskiene, Sabina, et al.
(författare)
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{alpha}1-antitrypsin Inhibits the Activity of the Matriptase Catalytic Domain in vitro.
- 2008
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Ingår i: American Journal of Respiratory Cell and Molecular Biology. - 1535-4989. ; 39:6, s. 631-637
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Tidskriftsartikel (refereegranskat)abstract
- Matriptase is a type II transmembrane protease which is characterized by an N-terminal transmembrane and multiple extracellular domains, in addition to the conserved extracellular serine protease catalytic domain. The expression pattern of matriptase suggests that this protease may play broad roles in the biology of surface lining epithelial cells. In this study we report that alpha1-antitrypsin (AAT), an endogenous inhibitor of serine proteases, inhibits the catalytic domain of human recombinant matriptase in vitro. Co-incubation of alpha1-antitrypsin with matriptase (at a molar ratio 1:2) resulted in the formation of heat stable complexes, clearly seen in sodium dodecyl sulfate (SDS) electrophoresis and Western blots. AAT was found to be a slow, tight-binding inhibitor of the catalytic domain of matriptase with a second order reaction rate constant of 0.31 x10(3) M(-1)s(-1). Notably, the oxidised form of AAT, which lacks serine protease inhibitor activity, failed to generate matriptase complexes and to inhibit matriptase activity. Since matriptase is involved in a number of physiological processes including activation of epithelial sodium channels, our findings offer considerable new insights into new regulatory function of AAT in vivo.
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| 6. |
- Janciauskiene, Sabina, et al.
(författare)
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alpha(1)-Antitrypsin, old dog, new tricks - alpha 1-Antitrypsin exerts in vitro anti-inflammatory activity in human monocytes by elevatin cAMP
- 2007
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Ingår i: Journal of Biological Chemistry. - 1083-351X. ; 282:12, s. 8573-8582
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Tidskriftsartikel (refereegranskat)abstract
- Regulation of serine protease activity is considered to be the sole mechanism for the function of alpha(1)-antitrypsin (AAT). However, recent reports of the anti-inflammatory effects of AAT are hard to reconcile with this classical mechanism. We discovered that two key activities of AAT in vitro, namely inhibition of endotoxin-stimulated tumor necrosis factor-a and enhancement of interleukin-10 in human monocytes, are mediated by an elevation of cAMP and activation of cAMP-dependent protein kinase A. As expected with this type of mechanism, the AAT mediated rise in cAMP and the impact on endotoxin-stimulated tumor necrosis factor-a and interleukin-10 was enhanced when the catabolism of cAMP was blocked by the phosphodiesterase inhibitor rolipram. These effects were still observed with modified forms of AAT lacking protease inhibitor activity.
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| 7. |
- Nilsson, Sara, et al.
(författare)
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Analysis of binding sites on complement factor I that are required for its activity.
- 2010
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Ingår i: Journal of Biological Chemistry. - 1083-351X. ; 285, s. 6235-6245
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Tidskriftsartikel (refereegranskat)abstract
- The central complement inhibitor factor I (FI) degrades activated complement factors C4b and C3b in the presence of cofactors such as C4b-binding protein, factor H, complement receptor 1 and membrane cofactor protein. FI is a serine protease composed of two chains; the light chain comprises the serine protease domain, while the heavy chain contains several domains: the FI and membrane attack complex domain (FIMAC), CD5, low density lipoprotein receptor 1 (LDLr1) and LDLr2 domains. In order to understand better how FI acts as a complement inhibitor, we used homology-based models of FI domains to predict potential binding sites. Specific amino acids were then mutated to yield 16 well-expressed mutants, which were then purified from media of eukaryotic cells for functional analyses. The Michaelis constant (Km) of all FI mutants towards a small substrate was not altered while some mutants showed increased maximum initial velocity (Vmax). All the mutations in the FIMAC domain affected the ability of FI to degrade C4b and C3b irrespective of the cofactor used whereas only some mutations in the CD5 and LDLr1/2 domains had similar effect. These same mutants also showed impaired binding to C3met. In conclusion, the FIMAC domain appears to harbor the main binding sites important for the ability of FI to degrade C4b and C3b.
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| 8. |
- Nita, Izabela
(författare)
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Alpha1-Antitrypsin: New insights into the biological role in vitro and in vivo
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Alpha1-Antitrypsin (AAT), an acute-phase glycoprotein produced predominantly in the liver by hepatocytes, but also by macrophages, pulmonary alveolar cells and intestinal epithelial cells, is a member of the SERPIN superfamily (SERine Protease INhibitors), and is one of the major inhibitors of neutrophil elastase in human plasma. Although AAT plays a critical role in regulating inflammation by inhibiting neutrophil serine proteases, recent studies suggest that AAT exhibits much broader anti-inflammatory activity. We have shown that Prolastin, a preparation of purified, pooled human plasma AAT used for augmentation therapy, inhibits bacterial endotoxin-induced pro-inflammatory responses in vitro and in vivo (Paper 1). We also discovered that two key activities of AAT in vitro, namely inhibition of lipopolysaccharide (LPS)-stimulated tumor necrosis factor alpha (TNFalpha) and enhancement of interleukin-10 (IL-10) in human monocytes, are mediated by an elevation of cAMP and activation of cAMP-dependent protein kinase A (Paper 2). The recognition of LPS is principally mediated by the membrane-bound or soluble form of the glycoprotein CD14 and CD14-associated signal transducer, toll-like receptor 4 (TLR4). We discovered that a longer term incubation (18 h) of monocytes with combined AAT/LPS results in a significant reduction in the expression of both CD14 and TLR4, and inhibition of TNFα, IL-1 and IL-8 expression as compared to LPS alone (Paper 3). Recent studies have also found that AAT is able to inhibit intracellular proteases. Matriptase, a cell surface serine protease involved in the activation of epithelial sodium channels, is one such protease. We found that AAT is a slow, tight-binding inhibitor of the catalytic domain of matriptase with a second order reaction rate constant of 0.31 x 103 M-1 s-1 (Paper 4). Because matriptase is known to be involved in the activation of epithelial sodium channels (ENaC), we performed a series of studies in Xenopus oocytes, injected with human alpha, beta, gamma ENaC cRNAs, in human lung Clara-like (H441) cells and in mice models, in order to investigate whether AAT has any effect on amiloride-sensitive Na+ transport and alveolar fluid clearance. We found that AAT can decrease amiloride-sensitive currents in oocytes and H441 cells, and reduce Na+-dependent alveolar fluid clearance in vivo. We believe that these effects were the result of AAT inactivation of membrane-bound proteases, such as matriptase and prostasin, present on the surface of oocytes and H441 cells (Paper 5). Findings that AAT inactivates the catalytic domain of matriptase in vitro and inhibits epithelial sodium transport both in vitro and in vivo (Paper 4 and 5) support the hypothesis postulate suggestion that the inhibition of matriptase by AAT may offer a pharmacological target for improving mucociliary clearance in both chronic obstructive pulmonary disease and cystic fibrosis. Several studies have shown that AAT inhibits the activity directly of caspase-3, an intracellular cysteine protease which plays an essential role in cell apoptosis. Taken together, recent findings highlight the potential involvement of AAT in several proteolytic pathways and also indicate that it has broader antiprotease activities than previously anticipated. Thus, the biological properties of AAT and their complex interplay with environmental factors appear to extend AAT functional activities well beyond those of protease inhibitor activity. AAT may exhibit anti-inflammatory activities independent of its protease inhibitor function, which suggests the existence of receptor-mediated AAT intracellular internalization, and provides further evidence of a broad protective role of AAT in vivo.
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| 9. |
- Nita, Izabela, et al.
(författare)
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alpha1-Antitrypsin regulates CD14 expression and soluble CD14 levels in human monocytes in vitro.
- 2007
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Ingår i: International Journal of Biochemistry & Cell Biology. - : Elsevier BV. - 1878-5875 .- 1357-2725. ; 39:Mar 1, s. 1165-1176
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Tidskriftsartikel (refereegranskat)abstract
- The recognition of bacterial lipopolysaccharide (LPS) is principally mediated by either membrane-bound or soluble form of the glycoprotein CD14 and CD14-associated signal transducer, toll-like receptor 4 (TLR4). Recent findings indicate that the serine protease inhibitor, alpha 1-antitrypsin (AAT), may not only afford protection against proteolytic injury, but may also neutralize microbial activities and affect regulation of innate immunity. We postulated that AAT affects monocyte responses to LPS by regulating CD14 expression and soluble CD 14 release. Here we show that a short-term (up to 2 h) monocyte exposure to AAT alone or in combination with LPS leads to a remarkable induction of CD 14 levels. In parallel, a short-term (2 h) cell exposure to AAT/LPS significantly enhances LPS-induced NF kappa B (p50 and p65) activation in conjunction with increased TNF alpha, IL-beta and IL-8 release. In contrast, longer term incubation (18 h) of monocytes with combined AAT/LPS results in a significant reduction in expression of both CD 14 and TLR4, inhibition of LPS-induced TNF alpha, IL-beta and IL-8 mRNA and protein expression. These findings provide evidence that AAT is an important regulator of CD14 expression and release in monocytes and suggest that AAT may be involved in LPS neutralization and prevention of over-activation of monocytes in vivo. (C) 2007 Elsevier Ltd. All rights reserved.
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| 10. |
- Nita, Izabela, et al.
(författare)
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Molecular characterization of two novel cases of complete complement inhibitor Factor I deficiency.
- 2011
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Ingår i: Molecular Immunology. - : Elsevier BV. - 1872-9142 .- 0161-5890. ; 48:8, s. 1068-1072
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Tidskriftsartikel (refereegranskat)abstract
- Factor I (FI) is the major complement inhibitor that degrades activated complement components C3b and C4b in the presence of specific cofactors. Complete FI deficiency results in secondary complement deficiency due to uncontrolled spontaneous alternative pathway activation. In this study we describe two unrelated patients with complete FI deficiency and undetectable alternative complement pathway activity. Both patients had experienced recurrent infections and arthralgia/arthritis. In one patient, analysis of genomic DNA revealed deletion of two adenine nucleotides in exon 2 of the CFI gene (c.133-134delAA), causing a frame shift and premature STOP codon/termination in the FIMAC (FI-membrane attack complex) domain (p.K45SfsX11). The other patient carried an A>T substitution in exon 6 (c.866A>T) encoding the LDLr2 (low density lipoprotein receptor) domain (p.D289V), resulting in an aspartic acid to valine change. Both patients were homozygous for the mutations while their healthy parents were heterozygous carriers. The mutations were introduced into recombinant FI, causing lack of FI expression and secretion upon transient transfection. Mutation p.K45SfsX11 theoretically allows expression of a 55 amino acid fragment of FI that lacks the serine protease domain, preventing proteolytic activity. In contrast, aspartic acid D289 is crucial for folding of FI. This report describes the molecular and functional consequences of two novel mutations of FI, providing a unique insight into the pathogenesis of complete FI deficiency in these patients.
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