1
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Totoki T, D' Alessandro-Gabazza CN, Toda M, Tonto PB, Takeshita A, Yasuma T, Nishihama K, Iwasa M, Horiki N, Takei Y, Gabazza EC. Protein S Exacerbates Chronic Liver Injury and Fibrosis. THE AMERICAN JOURNAL OF PATHOLOGY 2018; 188:1195-1203. [PMID: 29454753 DOI: 10.1016/j.ajpath.2018.01.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 12/09/2017] [Accepted: 01/11/2018] [Indexed: 12/24/2022]
Abstract
Protein S is a vitamin K-dependent glycoprotein produced mainly in the liver with anticoagulant, anti-inflammatory, immune-modulatory, and antiapoptotic properties. Protein S exacerbates acute liver injury by prolonging the survival of liver immune cells. However, the effect of protein S on chronic liver injury and fibrosis is unknown. Here, we investigated whether human protein S can affect chronic liver injury and fibrosis. Liver injury/fibrosis was induced by carbon tetrachloride injection in mice overexpressing human protein S and in wild-type mice. Human protein S transgenic mice receiving carbon tetrachloride showed significantly higher circulating levels of liver transaminases, increased liver expression of inflammatory cytokines, significantly more extended liver fibrosis, and areas with DNA breakage after chronic injury compared with wild-type mice. Wild-type mice infused with exogenous human protein S exhibited exacerbated liver injury and increased number of hepatic stellate cells compared with untreated mice. Human protein S inhibited apoptosis and increased Akt pathway activation in hepatic stellate cells. The antiapoptotic activity of protein S may play a role in chronic liver injury and subsequent liver fibrosis.
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Affiliation(s)
- Toshiaki Totoki
- Department of Gastroenterology and Hepatology, Mie University Graduate School of Medicine, Tsu, Japan
| | | | - Masaaki Toda
- Department of Immunology, Mie University Graduate School of Medicine, Tsu, Japan
| | - Prince Baffour Tonto
- Department of Immunology, Mie University Graduate School of Medicine, Tsu, Japan
| | - Atsuro Takeshita
- Department of Diabetes, Metabolism and Endocrinology, Mie University Graduate School of Medicine, Tsu, Japan
| | - Taro Yasuma
- Department of Immunology, Mie University Graduate School of Medicine, Tsu, Japan; Department of Diabetes, Metabolism and Endocrinology, Mie University Graduate School of Medicine, Tsu, Japan
| | - Kota Nishihama
- Department of Diabetes, Metabolism and Endocrinology, Mie University Graduate School of Medicine, Tsu, Japan
| | - Motoh Iwasa
- Department of Gastroenterology and Hepatology, Mie University Graduate School of Medicine, Tsu, Japan
| | - Noriyuki Horiki
- Department of Gastroenterology and Hepatology, Mie University Graduate School of Medicine, Tsu, Japan
| | - Yoshiyuki Takei
- Department of Gastroenterology and Hepatology, Mie University Graduate School of Medicine, Tsu, Japan
| | - Esteban C Gabazza
- Department of Immunology, Mie University Graduate School of Medicine, Tsu, Japan.
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2
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Urawa M, Kobayashi T, D'Alessandro-Gabazza CN, Fujimoto H, Toda M, Roeen Z, Hinneh JA, Yasuma T, Takei Y, Taguchi O, Gabazza EC. Protein S is protective in pulmonary fibrosis. J Thromb Haemost 2016; 14:1588-99. [PMID: 27172994 DOI: 10.1111/jth.13362] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Indexed: 01/10/2023]
Abstract
UNLABELLED Essentials Epithelial cell apoptosis is critical in the pathogenesis of idiopathic pulmonary fibrosis. Protein S, a circulating anticoagulant, inhibited apoptosis of lung epithelial cells. Overexpression of protein S in lung cells reduced bleomycin-induced pulmonary fibrosis. Intranasal therapy with exogenous protein S ameliorated bleomycin-induced pulmonary fibrosis. SUMMARY Background Pulmonary fibrosis is the terminal stage of interstitial lung diseases, some of them being incurable and of unknown etiology. Apoptosis plays a critical role in lung fibrogenesis. Protein S is a plasma anticoagulant with potent antiapoptotic activity. The role of protein S in pulmonary fibrosis is unknown. Objectives To evaluate the clinical relevance of protein S and its protective role in pulmonary fibrosis. Methods and Results The circulating level of protein S was measured in patients with pulmonary fibrosis and controls by the use of enzyme immunoassays. Pulmonary fibrosis was induced with bleomycin in transgenic mice overexpressing human protein S and wild-type mice, and exogenous protein S or vehicle was administered to wild-type mice; fibrosis was then compared in both models. Patients with pulmonary fibrosis had reduced circulating levels of protein S as compared with controls. Inflammatory changes, the levels of profibrotic cytokines, fibrosis score, hydroxyproline content in the lungs and oxygen desaturation were significantly reduced in protein S-transgenic mice as compared with wild-type mice. Wild-type mice treated with exogenous protein S showed significant decreases in the levels of inflammatory and profibrotic markers and fibrosis in the lungs as compared with untreated control mice. After bleomycin infusion, mice overexpressing human protein S showed significantly low caspase-3 activity, enhanced expression of antiapoptotic molecules and enhanced Akt and Axl kinase phosphorylation as compared with wild-type counterparts. Protein S also inhibited apoptosis of alveolar epithelial cells in vitro. Conclusions These observations suggest clinical relevance and a protective role of protein S in pulmonary fibrosis.
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Affiliation(s)
- M Urawa
- Department of Pulmonary and Critical Care Medicine, Tsu, Mie, Japan
- Department of Immunology, Tsu, Mie, Japan
| | - T Kobayashi
- Department of Pulmonary and Critical Care Medicine, Tsu, Mie, Japan
| | | | - H Fujimoto
- Department of Pulmonary and Critical Care Medicine, Tsu, Mie, Japan
| | - M Toda
- Department of Immunology, Tsu, Mie, Japan
| | - Z Roeen
- Department of Immunology, Tsu, Mie, Japan
| | - J A Hinneh
- Department of Immunology, Tsu, Mie, Japan
| | - T Yasuma
- Department of Immunology, Tsu, Mie, Japan
| | - Y Takei
- Department of Pulmonary and Critical Care Medicine, Tsu, Mie, Japan
- Department of Gastroenterology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - O Taguchi
- Department of Pulmonary and Critical Care Medicine, Tsu, Mie, Japan
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3
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Studer RA, Opperdoes FR, Nicolaes GAF, Mulder AB, Mulder R. Understanding the functional difference between growth arrest-specific protein 6 and protein S: an evolutionary approach. Open Biol 2015; 4:rsob.140121. [PMID: 25339693 PMCID: PMC4221892 DOI: 10.1098/rsob.140121] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Although protein S (PROS1) and growth arrest-specific protein 6 (GAS6) proteins are homologous with a high degree of structural similarity, they are functionally different. The objectives of this study were to identify the evolutionary origins from which these functional differences arose. Bioinformatics methods were used to estimate the evolutionary divergence time and to detect the amino acid residues under functional divergence between GAS6 and PROS1. The properties of these residues were analysed in the light of their three-dimensional structures, such as their stability effects, the identification of electrostatic patches and the identification potential protein-protein interaction. The divergence between GAS6 and PROS1 probably occurred during the whole-genome duplications in vertebrates. A total of 78 amino acid sites were identified to be under functional divergence. One of these sites, Asn463, is involved in N-glycosylation in GAS6, but is mutated in PROS1, preventing this post-translational modification. Sites experiencing functional divergence tend to express a greater diversity of stabilizing/destabilizing effects than sites that do not experience such functional divergence. Three electrostatic patches in the LG1/LG2 domains were found to differ between GAS6 and PROS1. Finally, a surface responsible for protein-protein interactions was identified. These results may help researchers to analyse disease-causing mutations in the light of evolutionary and structural constraints, and link genetic pathology to clinical phenotypes.
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Affiliation(s)
- Romain A Studer
- European Molecular Biology Laboratory-European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Fred R Opperdoes
- Laboratory of Biochemistry, de Duve Institute and Université catholique de Louvain, Brussels 1200, Belgium
| | - Gerry A F Nicolaes
- Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands
| | - André B Mulder
- Department of Laboratory Medicine, University Medical Centre Groningen, Groningen, The Netherlands
| | - René Mulder
- Department of Laboratory Medicine, University Medical Centre Groningen, Groningen, The Netherlands
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4
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Somajo S, Ahnström J, Fernandez-Recio J, Gierula M, Villoutreix BO, Dahlbäck B. Amino acid residues in the laminin G domains of protein S involved in tissue factor pathway inhibitor interaction. Thromb Haemost 2015; 113:976-87. [PMID: 25716664 DOI: 10.1160/th14-09-0803] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 01/05/2015] [Indexed: 11/05/2022]
Abstract
Protein S functions as a cofactor for tissue factor pathway inhibitor (TFPI) and activated protein C (APC). The sex hormone binding globulin (SHBG)-like region of protein S, consisting of two laminin G-like domains (LG1 and LG2), contains the binding site for C4b-binding protein (C4BP) and TFPI. Furthermore, the LG-domains are essential for the TFPI-cofactor function and for expression of full APC-cofactor function. The aim of the current study was to localise functionally important interaction sites in the protein S LG-domains using amino acid substitutions. Four protein S variants were created in which clusters of surface-exposed amino acid residues within the LG-domains were substituted. All variants bound normally to C4BP and were fully functional as cofactors for APC in plasma and in pure component assays. Two variants, SHBG2 (E612A, I614A, F265A, V393A, H453A), involving residues from both LG-domains, and SHBG3 (K317A, I330A, V336A, D365A) where residues in LG1 were substituted, showed 50-60 % reduction in enhancement of TFPI in FXa inhibition assays. For SHBG3 the decreased TFPI cofactor function was confirmed in plasma based thrombin generation assays. Both SHBG variants bound to TFPI with decreased affinity in surface plasmon resonance experiments. The TFPI Kunitz 3 domain is known to contain the interaction site for protein S. Using in silico analysis and protein docking exercises, preliminary models of the protein S SHBG/TFPI Kunitz domain 3 complex were created. Based on a combination of experimental and in silico data we propose a binding site for TFPI on protein S, involving both LG-domains.
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Affiliation(s)
| | | | | | | | | | - Björn Dahlbäck
- Björn Dahlbäck MD, PhD, Professor of Blood Coagulation Research, Lund University, Department of Translational Medicine, Division of Clinical Chemistry, Wallenberg laboratory, floor 6, University Hospital, Malmö, S-20502 Malmö, Sweden, E-mail:
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5
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Reglińska-Matveyev N, Andersson HM, Rezende SM, Dahlbäck B, Crawley JTB, Lane DA, Ahnström J. TFPI cofactor function of protein S: essential role of the protein S SHBG-like domain. Blood 2014; 123:3979-87. [PMID: 24740810 PMCID: PMC4064334 DOI: 10.1182/blood-2014-01-551812] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 04/09/2014] [Indexed: 01/17/2023] Open
Abstract
Protein S is a cofactor for tissue factor pathway inhibitor (TFPI), accelerating the inhibition of activated factor X (FXa). TFPI Kunitz domain 3 residue Glu226 is essential for enhancement of TFPI by protein S. To investigate the complementary functional interaction site on protein S, we screened 44 protein S point, composite or domain swap variants spanning the whole protein S molecule for their TFPI cofactor function using a thrombin generation assay. Of these variants, two protein S/growth arrest-specific 6 chimeras, with either the whole sex hormone-binding globulin (SHBG)-like domain (Val243-Ser635; chimera III) or the SHBG laminin G-type 1 subunit (Ser283-Val459; chimera I), respectively, substituted by the corresponding domain in growth arrest-specific 6, were unable to enhance TFPI. The importance of the protein S SHBG-like domain (and its laminin G-type 1 subunit) for binding and enhancement of TFPI was confirmed in FXa inhibition assays and using surface plasmon resonance. In addition, protein S bound to C4b binding protein showed greatly reduced enhancement of TFPI-mediated inhibition of FXa compared with free protein S. We show that binding of TFPI to the protein S SHBG-like domain enables TFPI to interact optimally with FXa on a phospholipid membrane.
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Affiliation(s)
| | - Helena M Andersson
- Centre for Haematology, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Suely M Rezende
- Department of Internal Medicine, Faculty of Medicine, Universidade Federal de Minas Gerais, Minas Gerais, Brazil; and
| | - Björn Dahlbäck
- Department of Laboratory Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - James T B Crawley
- Centre for Haematology, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - David A Lane
- Centre for Haematology, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Josefin Ahnström
- Centre for Haematology, Faculty of Medicine, Imperial College London, London, United Kingdom
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6
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Carlsson S, Dahlbäck B. Dependence on vitamin K-dependent protein S for eukaryotic cell secretion of the beta-chain of C4b-binding protein. J Biol Chem 2010; 285:32038-46. [PMID: 20693287 DOI: 10.1074/jbc.m110.148452] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The anticoagulant vitamin K-dependent protein S (PS) circulates in plasma in two forms, 30% free and 70% being bound to the complement regulatory protein C4b-binding protein (C4BP). The major C4BP isoform consists of 7 α-chains and 1 β-chain (C4BPβ(+)), the chains being linked by disulfide bridges. PS binds to the β-chain with high affinity. In plasma, PS is in molar excess over C4BPβ(+) and due to the high affinity, all C4BPβ(+) molecules contain a bound PS. Taken together with the observation that PS-deficient patients have decreased levels of C4BPβ(+), this raises the question of whether PS is important for secretion of the β-chain from the cell. To test this hypothesis, HEK293 cells were stably and transiently transfected with β-chain cDNA in combinations with cDNAs for PS and/or the α-chain. The concentration of β-chains in the medium increased after co-transfection with PS cDNA, but not by α-chain cDNA, suggesting secretion of the β-chains from the cells to be dependent on concomitant synthesis of PS, but not of the α-chains. Thus, β-chains that were not disulfide-linked to the α-chains were secreted in complex with PS, either as monomers or dimers. Pulse-chase demonstrated that the complexes between PS and β-chain were formed intracellularly, in the endoplasmic reticulum. In conclusion, our results demonstrate that successful secretion of β-chains depends on intracellular complex formation with PS, but not on the α-chains. This provides an explanation for the decreased β-chain levels observed in PS-deficient patients.
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Affiliation(s)
- Sofia Carlsson
- Department of Laboratory Medicine, Division of Clinical Chemistry, Lund University, Skåne University Hospital, SE-205 02 Malmö, Sweden
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7
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Bellido-Martín L, de Frutos PG. Vitamin K-dependent actions of Gas6. VITAMINS AND HORMONES 2008; 78:185-209. [PMID: 18374195 DOI: 10.1016/s0083-6729(07)00009-x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Gas6 (growth arrest-specific gene 6) is the last addition to the family of plasma vitamin K-dependent proteins. Gas6 was cloned and characterized in 1993 and found to be similar to the plasma anticoagulant protein S. Soon after it was recognized as a growth factor-like molecule, as it interacted with receptor tyrosine kinases (RTKs) of the TAM family; Tyro3, Axl, and MerTK. Since then, the role of Gas6, protein S, and the TAM receptors has been found to be important in inflammation, hemostasis, and cancer, making this system an interesting target in biomedicine. Gas6 employs a unique mechanism of action, interacting through its vitamin K-dependent Gla module with phosphatidylserine-containing membranes and through its carboxy-terminal LG domains with the TAM membrane receptors. The fact that these proteins are affected by anti-vitamin K therapy is discussed in detail.
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Affiliation(s)
- Lola Bellido-Martín
- Department of Cell Death and Proliferation, Institute for Biomedical Research of Barcelona, IIBB-CSIC-IDIBAPS, Barcelona 08036, Spain
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8
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Ricklin D, Lambris JD. Exploring the complement interaction network using surface plasmon resonance. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2007; 598:260-78. [PMID: 17892218 DOI: 10.1007/978-0-387-71767-8_19] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Daniel Ricklin
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia 19104-6100, USA.
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9
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Hansson K, Stenflo J. Post-translational modifications in proteins involved in blood coagulation. J Thromb Haemost 2005; 3:2633-48. [PMID: 16129023 DOI: 10.1111/j.1538-7836.2005.01478.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- K Hansson
- Department of Clinical Chemistry, Lund University, University Hospital Malmö, Malmö, Sweden.
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10
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Denis CV, Roberts SJ, Hackeng TM, Lenting PJ. In Vivo Clearance of Human Protein S in a Mouse Model. Arterioscler Thromb Vasc Biol 2005; 25:2209-15. [PMID: 16100035 DOI: 10.1161/01.atv.0000181760.55269.6b] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective—
To explore the effect of the Heerlen polymorphism and C4b-binding protein (C4BP) on protein S catabolism in vitro and in vivo.
Methods and Results—
Radiolabeled protein S was efficiently bound and intracellularly degraded by THP-1 macrophages, and both processes were strongly reduced in the presence of the protein S-carrier protein C4BP. To test whether C4BP displays a similar protective effect in vivo, survival experiments were performed in mice. In the absence of C4BP, radiolabeled human protein S disappeared in a biphasic manner (mean residence time [MRT] 2 hours). However, the presence of C4BP resulted in a 4-fold prolonged survival of protein S (MRT 8 hours;
P
<0.0001). We also applied this experimental model to recombinant protein S-Heerlen, a naturally occurring variant that contains a Ser460Pro substitution. These clearance experiments revealed a strongly decreased survival of recombinant protein S-S460P (MRT 0.6 hours;
P
=0.021), which could be compensated partially by C4BP (MRT 1.4 hours;
P
=0.012 compared with protein S-S460P).
Conclusion—
Protein S-S460P has a reduced survival in vivo, which may explain the low levels of free protein S in individuals carrying this polymorphism. Furthermore, C4BP prevents premature clearance of protein S and uses this ability to compensate the increased clearance of protein S-S460P.
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11
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Holak HM, Holak NH, Holak S, Holak SA, Szymaniec S. Venenastverschluss und Abduzensparese bei Protein-S-Mangel. Ophthalmologe 2005; 102:279-85. [PMID: 15138794 DOI: 10.1007/s00347-004-1032-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND Protein S deficiency, which exists in 0.7% of the population, is a risk factor for retinal vein branch occlusions and is inherited in an autosomal dominant manner. METHODS A genealogical study was carried out on three generations of one family who exhibited different venous occlusions and subsequent complications. RESULTS Four members of the family, spanning three generations, suffered from complications of venous thrombosis. In the first generation a great uncle died of complications from a deep leg venous thrombosis. In the second generation, the mother underwent a venous branch thrombosis at the age of 41 with a protein S activity of 18%. Subsequently, a palsy of the N. abducens developed with multiple cerebral lesions (presumably post-thrombotic) in the MRI. Fluorescein angiography showed a typical picture of a venous branch occlusion which had been treated by laser. In the third generation, the 16-year-old daughter developed iliac venous thrombosis and a pulmonary embolism with a protein S activity of 0%. The fluorescein angiography showed distinctively engorged veins. A 28-year-old daughter, with a protein S activity of 16%, remained asymptomatic, although fluorescein angiography demonstrated engorged veins. Protein C activity and APC resistance of all family members were normal. The chromosomal analysis of the family members revealed no morphological aberrations. CONCLUSION Protein S deficiency increases the risk of congenital thrombosis in young and middle-aged heterozygous individuals.
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Affiliation(s)
- H M Holak
- Gemeinschaftspraxis der Augenärzte im Rudolf-Virchow-Arztehaus, Salzgitter
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12
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Heeb MJ, Koenen RR, Fernández JA, Hackeng TM. Direct anticoagulant activity of protein S-C4b binding protein complex in Heerlen heterozygotes and normals. J Thromb Haemost 2004; 2:1766-73. [PMID: 15456488 DOI: 10.1111/j.1538-7836.2004.00901.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Plasma protein S normally circulates free (40%) or complexed with C4b-binding protein (PS-C4BP); only free protein S is a cofactor for activated protein C during factor (F) Va inactivation. Protein S-Heerlen lacks a carbohydrate group, leading to low plasma free protein S levels, but normal levels of PS-C4BP. OBJECTIVES Because protein S-Heerlen is not associated with thrombosis, we investigated whether PS-C4BP is directly anticoagulant in plasma and whether PS-Heerlen-C4BP has enhanced direct anticoagulant activity. METHODS An assay for protein S direct activity was applied to Heerlen-heterozygous plasmas. Free and complexed protein S were repeatedly isolated from normal and Heerlen-heterozygous plasmas and tested for direct anticoagulant activity in prothrombinase assays and in plasma. RESULTS Heerlen-heterozygous plasmas were deficient in free and total protein S antigen but had normal to high protein S direct anticoagulant activity. Purified Heerlen-heterozygous PS-C4BP was 7-fold more potent than normal PS-C4BP in inhibiting full prothrombinase activity, and 22-fold more potent in inhibiting prothrombin activation in the absence of FVa; it also specifically prolonged plasma clotting times 14-fold more than normal PS-C4BP. Heerlen-heterozygous PS-C4BP did not compete for limiting phospholipids any better than normal PS-C4BP. However, ligand blots and surface plasmon resonance studies showed that Heerlen-heterozygous PS-C4BP bound more avidly to FXa than did normal PS-C4BP (apparent Kd = 4.3 nm vs. 82 nm). CONCLUSIONS Plasma-derived PS-C4BP has direct anticoagulant activity in plasma and in purified systems. Enhanced direct activity of PS-Heerlen-C4BP may compensate for low free protein S levels and low cofactor activity in individuals with protein S-Heerlen.
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Affiliation(s)
- M J Heeb
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
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13
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Rich RL, Myszka DG. A survey of the year 2002 commercial optical biosensor literature. J Mol Recognit 2004; 16:351-82. [PMID: 14732928 DOI: 10.1002/jmr.649] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We have compiled 819 articles published in the year 2002 that involved commercial optical biosensor technology. The literature demonstrates that the technology's application continues to increase as biosensors are contributing to diverse scientific fields and are used to examine interactions ranging in size from small molecules to whole cells. Also, the variety of available commercial biosensor platforms is increasing and the expertise of users is improving. In this review, we use the literature to focus on the basic types of biosensor experiments, including kinetics, equilibrium analysis, solution competition, active concentration determination and screening. In addition, using examples of particularly well-performed analyses, we illustrate the high information content available in the primary response data and emphasize the impact of including figures in publications to support the results of biosensor analyses.
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Affiliation(s)
- Rebecca L Rich
- Center for Biomolecular Interaction Analysis, University of Utah, Salt Lake City, UT 84132, USA
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14
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Kask L, Trouw LA, Dahlbäck B, Blom AM. The C4b-binding Protein-Protein S Complex Inhibits the Phagocytosis of Apoptotic Cells. J Biol Chem 2004; 279:23869-73. [PMID: 15096498 DOI: 10.1074/jbc.c400159200] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The phagocytosis of apoptotic cells is a complex process involving numerous interactions between the target cell and the macrophage. We have examined a role of the major soluble inhibitor of the classic and lectin complement pathways, C4b-binding protein (C4BP), in the clearance of apoptotic cells. The major form of C4BP present in blood is composed of seven alpha-chains and one beta-chain, which binds protein S (PS). Approximately 70% of all PS in human plasma is trapped in such a complex and is able to localize C4BP to the surface of apoptotic cells due to the high affinity to phosphatidylserine. Free PS has recently been shown to enhance phagocytosis of apoptotic cells by macrophages. We observed a stimulatory effect of free PS on the engulfment of apoptotic cells (BL-41 and Jurkat) by primary human macrophages or THP-1 cells and a decrease of activity in serum depleted of PS in agreement with previous results. However, we also show that the process is strongly inhibited in the presence of the C4BP-PS complex. Addition of the C4BP-PS complex to serum deficient in both molecules abolished the enhancing effect of serum on phagocytosis. The effect of both free PS and the C4BP-PS complex could be inhibited with monoclonal antibody directed against the Gla domain of PS. Although the presence of the C4BP-PS complex on apoptotic cells may lead to decreased phagocytosis, it may still be beneficial to the host, since it could prevent secondary necrosis because it inhibits further complement attack.
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Affiliation(s)
- Lena Kask
- Lund University, The Wallenberg Laboratory, Department of Clinical Chemistry, University Hospital Malmö; S-205 02 Malmö, Sweden
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15
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Rezende SM, Simmonds RE, Lane DA. Coagulation, inflammation, and apoptosis: different roles for protein S and the protein S-C4b binding protein complex. Blood 2004; 103:1192-201. [PMID: 12907438 DOI: 10.1182/blood-2003-05-1551] [Citation(s) in RCA: 133] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Protein S (PS) has an established role as an important cofactor to activated protein C (APC) in the degradation of coagulation cofactors Va and VIIIa. This anticoagulant role is evident from the consequences of its deficiency, when there is an increased risk of venous thromboembolism. In human plasma, PS circulates approximately 40% as free PS (FPS) and 60% in complex with C4b-binding protein (C4BP). Formation of this complex results in loss of PS cofactor function, and C4BP can then modulate the anticoagulant activity of APC. It had long been predicted that the complex could act as a bridge between coagulation and inflammation due to the involvement of C4BP in regulating complement activation. This prediction was recently supported by the demonstration of binding of the PS-C4BP complex to apoptotic cells. This review aims to summarize recent findings on the structure and functions of PS, the basis and importance of its deficiency, its interaction with C4BP, and the possible physiologic and pathologic importance of the PS-C4BP interaction.
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Affiliation(s)
- Suely Meireles Rezende
- Research Laboratory, Fundação HEMOMINAS, Alameda Ezequiel Dias, 321 Belo Horizonte-MG-Brazil, 30130-110.
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16
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Abstract
The protein C (PC) anticoagulant system provides specific and efficient control of blood coagulation. The system comprises circulating or membrane-bound protein components that take part in complicated multimolecular protein complexes being assembled on specific cellular phospholipid membranes. Each of the participating proteins is composed of multiple domains, many of which are known at the level of their three-dimensional structures. The key component of the PC system, the vitamin K-dependent PC, circulates in blood as zymogen to an anticoagulant serine protease. Activation is achieved on the surface of endothelial cells by thrombin bound to the membrane protein thrombomodulin. The endothelial PC receptor binds the Gla domain of PC and stimulates the activation. Activated PC (APC) modulates the activity of blood coagulation by specific proteolytic cleavages of a limited number of peptide bonds in factor (F)VIIIa and FVa, cofactors in the activation of FX and prothrombin, respectively. These reactions occur on the surface of negatively charged phospholipid membranes and are stimulated by the vitamin K-dependent protein S. Regulation of FVIIIa activity by APC is stimulated not only by protein S but also by FV, which, like thrombin, is a Janus-faced protein with both pro- and anticoagulant potential. However, whereas the properties of thrombin are modulated by protein-protein interactions, the specificity of FV function is governed by proteolysis by pro- or anti-coagulant enzymes. The molecular recognition of the PC system is beginning to be unravelled and provides insights into a fascinating and intricate molecular scenario.
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Affiliation(s)
- B Dahlbäck
- Department of Laboratory Medicine, Division of Clinical Chemistry, Lund University, The Wallenberg Laboratory, University Hospital Malmö, Malmö, Sweden.
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17
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Saposnik B, Borgel D, Aiach M, Gandrille S. Functional properties of the sex-hormone-binding globulin (SHBG)-like domain of the anticoagulant protein S. EUROPEAN JOURNAL OF BIOCHEMISTRY 2003; 270:545-55. [PMID: 12542704 DOI: 10.1046/j.1432-1033.2003.03423.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Protein S (PS) possesses a sex-hormone-binding globulin (SHBG)-like domain in place of the serine-protease domain found in other vitamin K-dependent plasma proteins. This SHBG-like domain is able to bind a complement fraction, C4b-binding protein (C4b-BP). To establish whether the PS SHBG-like domain can fold normally in the absence of other domains, and to obtain information on the specific functions of this region, we expressed the PS SHBG-like domain alone or together with its adjacent domain EGF4. The folding of the two recombinant modules was studied by analyzing their binding to C4b-BP. The apparent dissociation constants of this interaction indicated that both recombinant modules adopted the conformation of native PS, indicating that the PS SHBG-like region is an independent folding unit. We also obtained the first direct evidence that the SHBG-like domain alone is sufficient to support the interaction with C4b-BP. In addition, both recombinant modules were able to bind Ca2+ directly, as shown by the migration shift in agarose gel electrophoresis in the presence of Ca2+, together with the results of equilibrium dialysis and the functional effect of Ca2+ on the C4b-BP/PS interaction, confirming the presence of one Ca2+ binding site within the SHBG-like domain. Neither recombinant module exhibited activated protein C (aPC) cofactor activity in a clotting assay, suggesting that the PS SHBG-like region must be part of the intact molecule for it to contribute to aPC cofactor activity, possibly by constraining the different domains in a conformation that permits optimal interaction with aPC.
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Affiliation(s)
- Béatrice Saposnik
- Unité INSERM 428, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris V, Paris, France
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18
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Sasaki T, Knyazev PG, Cheburkin Y, Göhring W, Tisi D, Ullrich A, Timpl R, Hohenester E. Crystal structure of a C-terminal fragment of growth arrest-specific protein Gas6. Receptor tyrosine kinase activation by laminin G-like domains. J Biol Chem 2002; 277:44164-70. [PMID: 12218057 DOI: 10.1074/jbc.m207340200] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Receptor tyrosine kinases of the Axl family are activated by Gas6, the product of growth arrest-specific gene 6. Gas6-Axl signaling is implicated in cell survival, adhesion, and migration. The receptor-binding site of Gas6 is located within a C-terminal pair of laminin G-like (LG) domains that do not resemble any other receptor tyrosine kinase ligand. We report the crystal structure at 2.2-A resolution of a Gas6 fragment spanning both LG domains (Gas6-LG). The structure reveals a V-shaped arrangement of LG domains strengthened by an interdomain calcium-binding site. LG2 of Gas6-LG contains two unusual features: an alpha-helix cradled by one edge of the LG beta-sandwich and a conspicuous patch of surface-exposed hydrophobic residues. Mutagenesis of some residues in this patch reduces Gas6-LG binding to the extracellular domain of Axl as well as Axl activation in glioblastoma cells, identifying a component of the receptor-binding site of Gas6.
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Affiliation(s)
- Takako Sasaki
- Max-Planck-Institut für Biochemie, D-82152 Martinsried, Germany
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19
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Berggard T, Szczepankiewicz O, Thulin E, Linse S. Myo-inositol monophosphatase is an activated target of calbindin D28k. J Biol Chem 2002; 277:41954-9. [PMID: 12176979 DOI: 10.1074/jbc.m203492200] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Calbindin D(28k) (calbindin) is a member of the calmodulin superfamily of Ca(2+)-binding proteins. An intracellular target of calbindin was discovered using bacteriophage display. Human recombinant calbindin was immobilized on magnetic beads and used in affinity purification of phage-displayed peptides from a random 12-mer peptide library. One sequence, SYSSIAKYPSHS, was strongly selected both in the presence of Mg(2+) and in the presence of Ca(2+). Homology search against the protein sequence data base identified a closely similar sequence, ISSIKEKYPSHS, at residues 55-66 in myo-inositol-1(or 4)-monophosphatase (IMPase, EC ), which constitute a strongly conserved and exposed region in the three-dimensional structure. IMPase is a key enzyme in the regulation of the activity of the phosphatidylinositol-signaling pathway. It catalyzes the hydrolysis of myo-inositol-1(or 4)-monophosphate to form free myo-inositol, maintaining a supply that represents the precursor for inositol phospholipid second messenger signaling systems. Fluorescence spectroscopy showed that isolated calbindin and IMPase interact with an apparent equilibrium dissociation constant, K(D), of 0.9 microm. Both apo and Ca(2+)-bound calbindin was found to activate IMPase up to 250-fold, depending on the pH and substrate concentration. The activation is most pronounced at conditions that otherwise lead to a very low activity of IMPase, i.e. at reduced pH and at low substrate concentration.
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Affiliation(s)
- Tord Berggard
- Department of Biophysical Chemistry, Lund University, Chemical Centre, P.O. Box 124, Sweden
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