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Ho-Tin-Noé B, Desilles JP, Mazighi M. Thrombus composition and thrombolysis resistance in stroke. Res Pract Thromb Haemost 2023; 7:100178. [PMID: 37538503 PMCID: PMC10394565 DOI: 10.1016/j.rpth.2023.100178] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 04/14/2023] [Accepted: 05/05/2023] [Indexed: 08/05/2023] Open
Abstract
A State of the Art lecture titled "Thrombus Composition and Thrombolysis Resistance in Stroke" was presented at the ISTH Congress in 2022. Intravenous thrombolysis (IVT) remains the only pharmacologic option to re-establish cerebral perfusion at the acute phase of ischemic stroke. IVT is based on the administration of recombinant tissue plasminogen activator with the objective of dissolving fibrin, the major fibrillar protein component of thrombi. Almost 30 years on from its introduction, although the clinical benefits of IVT have been clearly demonstrated, IVT still suffers from a relatively low efficacy, with a rate of successful early recanalization below 50% overall. Analyses of thrombectomy-recovered acute ischemic stroke (AIS) thrombi have shown that apart from occlusion site, thrombus length, and collateral status, AIS thrombus structure and composition are also important modulators of IVT efficacy. In this article, after a brief presentation of IVT principle and current knowledge on IVT resistance, we review recent findings on how compaction and structural alterations of fibrin together with nonfibrin thrombus components such as neutrophil extracellular traps and von Willebrand factor interfere with IVT in AIS. We further discuss how these new insights could soon result in the development of original adjuvant therapies for improved IVT in AIS. Finally, we summarize relevant new data presented during the 2022 ISTH Congress.
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Affiliation(s)
- Benoit Ho-Tin-Noé
- Université Paris Cité, Inserm, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France
| | - Jean-Philippe Desilles
- Université Paris Cité, Inserm, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France
- Interventional Neuroradiology Department and Biological Resources Center, Rothschild Foundation Hospital, Paris, France
| | - Mikael Mazighi
- Université Paris Cité, Inserm, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France
- Interventional Neuroradiology Department and Biological Resources Center, Rothschild Foundation Hospital, Paris, France
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Patten DA, Wilkinson AL, O'Keeffe A, Shetty S. Scavenger Receptors: Novel Roles in the Pathogenesis of Liver Inflammation and Cancer. Semin Liver Dis 2022; 42:61-76. [PMID: 34553345 PMCID: PMC8893982 DOI: 10.1055/s-0041-1733876] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The scavenger receptor superfamily represents a highly diverse collection of evolutionarily-conserved receptors which are known to play key roles in host homeostasis, the most prominent of which is the clearance of unwanted endogenous macromolecules, such as oxidized low-density lipoproteins, from the systemic circulation. Members of this family have also been well characterized in their binding and internalization of a vast range of exogenous antigens and, consequently, are generally considered to be pattern recognition receptors, thus contributing to innate immunity. Several studies have implicated scavenger receptors in the pathophysiology of several inflammatory diseases, such as Alzheimer's and atherosclerosis. Hepatic resident cellular populations express a diverse complement of scavenger receptors in keeping with the liver's homeostatic functions, but there is gathering interest in the contribution of these receptors to hepatic inflammation and its complications. Here, we review the expression of scavenger receptors in the liver, their functionality in liver homeostasis, and their role in inflammatory liver disease and cancer.
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Affiliation(s)
- Daniel A. Patten
- National Institute for Health Research Birmingham Liver Biomedical Research Unit, Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
- Centre for Liver and Gastrointestinal Research, Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
| | - Alex L. Wilkinson
- National Institute for Health Research Birmingham Liver Biomedical Research Unit, Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
- Centre for Liver and Gastrointestinal Research, Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
| | - Ayla O'Keeffe
- National Institute for Health Research Birmingham Liver Biomedical Research Unit, Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
- Centre for Liver and Gastrointestinal Research, Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
| | - Shishir Shetty
- National Institute for Health Research Birmingham Liver Biomedical Research Unit, Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
- Centre for Liver and Gastrointestinal Research, Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
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Wilkinson AL, Qurashi M, Shetty S. The Role of Sinusoidal Endothelial Cells in the Axis of Inflammation and Cancer Within the Liver. Front Physiol 2020; 11:990. [PMID: 32982772 PMCID: PMC7485256 DOI: 10.3389/fphys.2020.00990] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 07/20/2020] [Indexed: 12/12/2022] Open
Abstract
Liver sinusoidal endothelial cells (LSEC) form a unique barrier between the liver sinusoids and the underlying parenchyma, and thus play a crucial role in maintaining metabolic and immune homeostasis, as well as actively contributing to disease pathophysiology. Whilst their endocytic and scavenging function is integral for nutrient exchange and clearance of waste products, their capillarisation and dysfunction precedes fibrogenesis. Furthermore, their ability to promote immune tolerance and recruit distinct immunosuppressive leukocyte subsets can allow persistence of chronic viral infections and facilitate tumour development. In this review, we present the immunological and barrier functions of LSEC, along with their role in orchestrating fibrotic processes which precede tumourigenesis. We also summarise the role of LSEC in modulating the tumour microenvironment, and promoting development of a pre-metastatic niche, which can drive formation of secondary liver tumours. Finally, we summarise closely inter-linked disease pathways which collectively perpetuate pathogenesis, highlighting LSEC as novel targets for therapeutic intervention.
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Affiliation(s)
| | | | - Shishir Shetty
- Centre for Liver and Gastrointestinal Research, Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
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Nedaeinia R, Faraji H, Javanmard SH, Ferns GA, Ghayour-Mobarhan M, Goli M, Mashkani B, Nedaeinia M, Haghighi MHH, Ranjbar M. Bacterial staphylokinase as a promising third-generation drug in the treatment for vascular occlusion. Mol Biol Rep 2019; 47:819-841. [PMID: 31677034 DOI: 10.1007/s11033-019-05167-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 10/29/2019] [Indexed: 12/12/2022]
Abstract
Vascular occlusion is one of the major causes of mortality and morbidity. Blood vessel blockage can lead to thrombotic complications such as myocardial infarction, stroke, deep venous thrombosis, peripheral occlusive disease, and pulmonary embolism. Thrombolytic therapy currently aims to rectify this through the administration of recombinant tissue plasminogen activator. Research is underway to design an ideal thrombolytic drug with the lowest risk. Despite the potent clot lysis achievable using approved thrombolytic drugs such as alteplase, reteplase, streptokinase, tenecteplase, and some other fibrinolytic agents, there are some drawbacks, such as high production cost, systemic bleeding, intracranial hemorrhage, vessel re-occlusion by platelet-rich and retracted secondary clots, and non-fibrin specificity. In comparison, bacterial staphylokinase, is a new, small-size plasminogen activator, unlike bacterial streptokinase, it hinders the systemic degradation of fibrinogen and reduces the risk of severe hemorrhage. A fibrin-bound plasmin-staphylokinase complex shows high resistance to a2-antiplasmin-related inhibition. Staphylokinase has the potential to be considered as a promising thrombolytic agent with properties of cost-effective production and the least side effects.
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Affiliation(s)
- Reza Nedaeinia
- Isfahan Cardiovascular Research Center, Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Habibollah Faraji
- Molecular Medicine Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas, Iran. .,Department of Laboratory Sciences, Faculty of Para-Medicine, Hormozgan University of Medical Sciences, Bandar Abbas, Iran.
| | - Shaghayegh Haghjooye Javanmard
- Applied Physiology Research Center, Cardiovascular Research Institute, Isfahan University of Medical Science, Isfahan, Iran
| | - Gordon A Ferns
- Brighton and Sussex Medical School, Division of Medical Education, Falmer, Brighton, Sussex, BN1 9PH, UK
| | - Majid Ghayour-Mobarhan
- Metabolic Syndrome Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mohammad Goli
- Department of Food Science and Technology, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran
| | - Baratali Mashkani
- Department of Medical Biochemistry, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mozhdeh Nedaeinia
- Young Researchers and Elite Club, Marvdasht Branch, Islamic Azad University, Marvdasht, Iran
| | - Mohammad Hossein Hayavi Haghighi
- Department of Health Information Management, Faculty of Para-Medicine, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Maryam Ranjbar
- Advanced Materials Research Center, Department of Materials Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran.,Deputy of Food and Drug, Isfahan University of Medical Sciences, Isfahan, Iran
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Scale up and pharmacokinetic study of a novel mutated chimeric tissue plasminogen activator (mt-PA) in rats. Sci Rep 2017; 7:43028. [PMID: 28223717 PMCID: PMC5320447 DOI: 10.1038/srep43028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 01/17/2017] [Indexed: 11/08/2022] Open
Abstract
Because of high mortality caused by cardiovascular diseases, various fibrinolytic agents with diverse pharmacokinetic and pharmacodynamic properties have been developed. A novel mutated chimeric tissue plasminogen activator (mt-PA) was developed by the removal of first three domains of t-PA, insertion of GHRP sequence and mutation towards resistance to plasminogen activator inhibitor-1 (PAI-1). Mt-PA protein was expressed in Expi293F cells. The expression level of mt-PA was found to be 5000 IU/mL. Following purification, the pharmacokinetic properties of mt-PA were evaluated in three doses in rats. Data related to mt-PA were best fitted to two compartment model. With the increase in dose, the Area Under the plasma concentration-time Curve (AUC0→∞) increased. The elimination half-life (t1/2) of mt-PA was in the range of 19.1–26.1 min in three doses while that of Alteplase was 8.3 min. The plasma clearance (CLp) of mt-PA ranged from 3.8 to 5.9 mL/min in three doses, which was several times lower than that of Alteplase (142.6 mL/min). The mean residence time (MRT) of mt-PA ranged from 23.3–31.8 min in three doses, which was 4–5 times greater than that of Alteplase (6 min). Mt-PA showed extended half-life and mean residence time and is a good candidate for further clinical studies.
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Rijken DC, Kock EL, Guimarães AHC, Talens S, Darwish Murad S, Janssen HLA, Leebeek FWG. Evidence for an enhanced fibrinolytic capacity in cirrhosis as measured with two different global fibrinolysis tests. J Thromb Haemost 2012; 10:2116-22. [PMID: 22906184 DOI: 10.1111/j.1538-7836.2012.04901.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND AND OBJECTIVES It has been known for a long time that cirrhosis is associated with hyperfibrinolysis, which might contribute to an increased risk and severity of bleeding. However, recent papers have questioned the presence of a hyperfibrinolytic state in cirrhotic patients and postulated a rebalanced system owing to concomitant changes in both pro- and anti-fibrinolytic factors. Therefore we re-investigated the fibrinolytic state of cirrhotic patients using two different overall tests including a recently developed test for global fibrinolytic capacity (GFC) using whole blood. PATIENTS AND METHODS Blood was collected from 30 healthy controls and 75 patients with cirrhosis of varying severity (34 Child-Pugh A, 28 Child-Pugh B and 13 Child-Pugh C). The plasma clot lysis time (CLT), which is inversely correlated with fibrinolysis, was determined as well as the GFC. RESULTS The mean CLT was 74.5 min in the controls and decreased significantly to 66.9 min in Child-Pugh class A patients, 59.3 min in class B patients and 61.0 min in class C patients, and hyperfibrinolysis existed in 40% of the patients. The median GFC was 1.7 μg mL(-1) in the controls and increased significantly to 4.0 μg mL(-1) in Child-Pugh class A patients, 11.1 μg mL(-1) in class B patients and 22.5 μg mL(-1) in class C patients, and hyperfibrinolysis existed in 43% of the patients. Taken together, 60% of the patients showed hyperfibrinolysis in at least one of the two global assays. CONCLUSION A rebalanced fibrinolytic system may occur, but hyperfibrinolysis is found in the majority of patients with cirrhosis.
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Affiliation(s)
- D C Rijken
- Department of Hematology, Erasmus University Medical Center, Rotterdam, the Netherlands.
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Neumann AK, Jacobson K. A novel pseudopodial component of the dendritic cell anti-fungal response: the fungipod. PLoS Pathog 2010; 6:e1000760. [PMID: 20169183 PMCID: PMC2820528 DOI: 10.1371/journal.ppat.1000760] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2009] [Accepted: 01/11/2010] [Indexed: 02/02/2023] Open
Abstract
Fungal pathologies are seen in immunocompromised and healthy humans. C-type lectins expressed on immature dendritic cells (DC) recognize fungi. We report a novel dorsal pseudopodial protrusion, the “fungipod”, formed by DC after contact with yeast cell walls. These structures have a convoluted cell-proximal end and a smooth distal end. They persist for hours, exhibit noticeable growth and total 13.7±5.6 µm long and 1.8±0.67 µm wide at the contact. Fungipods contain clathrin and an actin core surrounded by a sheath of cortactin. The actin cytoskeleton, but not microtubules, is required for fungipod integrity and growth. An apparent rearward flow (225±55 nm/second) exists from the zymosan contact site into the distal fungipod. The phagocytic receptor Dectin-1 is not required for fungipod formation, but CD206 (Mannose Receptor) is the generative receptor for these protrusions. The human pathogen Candida parapsilosis induces DC fungipod formation strongly, but the response is species specific since the related fungal pathogens Candida tropicalis and Candida albicans induce very few and no fungipods, respectively. Our findings show that fungipods are dynamic actin-driven cellular structures involved in fungal recognition by DC. They may promote yeast particle phagocytosis by DC and are a specific response to large (i.e., 5 µm) particulate ligands. Our work also highlights the importance of this novel protrusive structure to innate immune recognition of medically significant Candida yeasts in a species specific fashion. Yeasts are normal microbial commensals of humans and a significant source of opportunistic infections, especially in immunocompromised individuals. We report a novel cellular protrusive structure, the fungipod, which participates in the host-microbe interaction between human immature dendritic cells (DC) and yeasts. The fungipod's structure is based on and propelled by a robust process of local actin cytoskeleton growth at the DC-yeast contact site, and this cytoskeletal remodeling results in a durable tubular structure over 10 µm long connecting the dorsal DC membrane and yeast. The fungal cell wall polysaccharides mannan and chitin trigger fungipod formation by stimulating the carbohydrate pattern recognition receptor CD206. Fungipods are part of a specific response to large particulate objects (i.e., yeast), and they may promote the human immature DC's relatively poor phagocytosis of yeast. The human fungal pathogen, Candida parapsilosis, induces a strong fungipod response from DC, and this response is highly species specific since the related pathogens Candida albicans and Candida tropicalis induce fungipods rarely. Our work highlights a novel cell biological element of fungal recognition by the innate immune system.
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Affiliation(s)
- Aaron K. Neumann
- Department of Cell & Developmental Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Ken Jacobson
- Department of Cell & Developmental Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- * E-mail:
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Kawasaki N, Itoh S, Hashii N, Takakura D, Qin Y, Huang X, Yamaguchi T. The significance of glycosylation analysis in development of biopharmaceuticals. Biol Pharm Bull 2009; 32:796-800. [PMID: 19420744 DOI: 10.1248/bpb.32.796] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Many glycoproteins and glycosaminoglycans are approved for clinical use. Carbohydrate moieties in biopharmaceuticals affect not only their physicochemical properties and thermal stability, but also their reactivity with their receptors and circulating half-life. Modification of glycans is one target of drug design for enhancement of efficacy. Meanwhile, there have been reports of serious adverse events caused by some carbohydrates. It is crucial to maintain the constancy of carbohydrate moieties for the efficient and safe use of glycosylated biopharmaceuticals. On the other hand, for scientific, safety-related, and economic reasons, changes in the manufacturing process are frequently made either during the development or after the approval of new biopharmaceuticals. Furthermore, the development of biosimilar glycoprotein products has been attempted by different manufacturers. Changes in pharmaceutical manufacturing processes possibly cause alteration of glycosylation and raise concerns about alteration of their quality, safety, and efficacy. In this review we provide some current topics of glycosylated biopharmaceuticals from the viewpoints of efficacy, safety, and the manufacturing process and discuss the significance of glycosylation analysis for development of biopharmaceuticals.
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Affiliation(s)
- Nana Kawasaki
- Division of Biological Chemistry & Biologicals, National Institute of Health Sciences, Tokyo, Japan.
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Abstract
Thrombosis risk is multifactorial, with interaction of hereditary risk factors and acquired environmental and clinical conditions. Newborns are at particular risk for thrombotic emergencies secondary to the unique properties of their hemostatic system, influences of the maternal-fetal environment, and perinatal complications and interventions. Thrombotic complications range from arterial and venous catheter thrombosis to purpura fulminans. Prompt identification and appropriate management of thrombotic emergencies is critical in avoiding limb-, organ-, and life-threatening complications. Treatment strategies have been extrapolated from adult literature but clinical experience from small-scale neonatal studies has resulted in therapeutic guidelines, which should be individualized for each neonate, taking into consideration age and clinical status.
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Alcon-LePoder S, Drouet MT, Roux P, Frenkiel MP, Arborio M, Durand-Schneider AM, Maurice M, Le Blanc I, Gruenberg J, Flamand M. The secreted form of dengue virus nonstructural protein NS1 is endocytosed by hepatocytes and accumulates in late endosomes: implications for viral infectivity. J Virol 2005; 79:11403-11. [PMID: 16103191 PMCID: PMC1193635 DOI: 10.1128/jvi.79.17.11403-11411.2005] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The flavivirus nonstructural protein NS1 is expressed as three discrete species in infected mammalian cells: an intracellular, membrane-associated form essential for viral replication, a cell surface-associated form that may be involved in signal transduction, and a secreted form (sNS1), the biological properties of which remain elusive. To determine the distribution of the dengue virus (DEN) sNS1 protein in vivo, we have analyzed by immunohistological means the tissue tropism of purified DEN sNS1 injected intravenously into adult mice. The sNS1 protein was found predominantly associated with the liver, where hepatocytes appeared to represent a major target cell. We further showed that sNS1 could be efficiently endocytosed by human Huh7 and HepG2 hepatocytes in vitro. After its internalization, the protein was detected intracellularly for at least 48 h without being substantially degraded. Colocalization studies of sNS1 with markers of the endolysosomal compartments revealed that the protein was specifically targeted to lysobisphosphatidic acid-rich structures reminiscent of late endosomes, as confirmed by electron microscopy. Intracellular accumulation of sNS1 in Huh7 cells enhanced the fluid phase uptake of rhodamine-labeled dextran. Furthermore, preincubation of Huh7 cells with sNS1 increased dengue virus production after infection with the homologous strain of DEN-1 virus. Our results demonstrate that the accumulation of DEN sNS1 in the late endosomal compartment of hepatocytes potentializes subsequent dengue virus infection in vitro, raising the possibility that sNS1 may contribute to viral propagation in vivo.
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Affiliation(s)
- Sophie Alcon-LePoder
- U.P. Interactions Moléculaires Flavivirus-Hôtes, Institut Pasteur, Paris, France
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Nagaoka MR, Strital E, Kouyoumdjian M, Borges DR. Participation of a galectin-dependent mechanism in the hepatic clearance of tissue-type plasminogen activator and plasma kallikrein. Thromb Res 2002; 108:257-62. [PMID: 12617990 DOI: 10.1016/s0049-3848(02)00393-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Marcia R Nagaoka
- Laboratory of Experimental Hepatology, Department of Biochemistry, Universidade Federal de São Paulo (UNIFESP), Brazil
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13
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Noguchi T, Matsuyama S, Akao M, Hagiwara H, Uno S, Seki T, Ariga T. Induction of hepatic tissue-type plasminogen activator and type 1 plasminogen activator-inhibitor gene expressions and appearance of their translation products in the bile following acute liver injury in rats. Thromb Res 2001; 104:283-91. [PMID: 11728530 DOI: 10.1016/s0049-3848(01)00370-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND/AIMS The plasminogen activator (PA)-plasmin system is primarily involved in fibrinolysis, but is also in the patho/physiological events in which breakdown of extracellular matrices is evoked topically. In this present study, we examined the expression of fibrinolytic factors, tissue-type PA (t-PA) and Type 1 PA inhibitor (PAI-1), in acute liver injury. METHODS Acute liver injury was produced in rats by the intraperitoneal administration of carbon tetrachloride (CCl(4)). Plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities were measured to verify the hepatocellular damage. t-PA and PAI-1 gene expressions were measured by Northern blotting, and the cell type(s) expressing these genes was identified by in situ hybridization. t-PA and PAI-1 levels were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS A single intraperitoneal administration of CCl(4) caused severe acute parenchymatous liver injury. Both t-PA and PAI-1 gene expressions were induced by the acute liver injury, and plasma t-PA and PAI-1 concentrations were also increased. In situ hybridization studies demonstrated that the hepatocytes were the cells expressing t-PA and PAI-1 genes during the acute liver injury. t-PA was also augmented in the bile, whereas PAI-1 was decreased there. CONCLUSIONS t-PA and PAI-1 gene expressions are induced in the hepatocytes of rats with acute liver injury. These fibrinolytic factors induced by liver injury may play important roles in liver regeneration.
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Affiliation(s)
- T Noguchi
- Department of Nutrition and Physiology, Nihon University Graduate School of Applied Life Sciences, Nihon University College of Bioresource Sciences, 1866 Kameino, Fujisawa, Kanagawa 252-8510, Japan
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14
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Szolnoky G, Bata-Csörgö Z, Kenderessy AS, Kiss M, Pivarcsi A, Novák Z, Nagy Newman K, Michel G, Ruzicka T, Maródi L, Dobozy A, Kemény L. A mannose-binding receptor is expressed on human keratinocytes and mediates killing of Candida albicans. J Invest Dermatol 2001; 117:205-13. [PMID: 11511295 DOI: 10.1046/j.1523-1747.2001.14071.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Human keratinocytes are known to kill Candida albicans in vitro, but the mechanism of killing is not yet understood. Here, we demonstrate that spontaneous, ultraviolet-B-light-induced, alpha-melanocyte-stimulating-hormone-induced, and interleukin-8-induced Candida killing by keratinocytes can be inhibited with mannan and mannosylated bovine serum albumin (Man-BSA). A polyclonal goat serum raised against the human macrophage mannose receptor stained suprabasal keratinocytes, but no staining was observed on keratinocytes with a monoclonal antibody (mAb15) specific for the human macrophage mannose receptor. Mannose-affinity chromatography of keratinocyte extract isolated a 200 kDa protein, and on the Western blot the goat antiserum reacted with a 200 kDa protein. In radioligand binding studies, the binding of 125I-Man-BSA to human keratinocytes was inhibited by mannan in a concentration-dependent manner. Analysis of the binding revealed a single class keratinocyte mannose receptor with a KD of 1.4 x 10(-8) M and a Bmax of 1 x 10(4) binding sites per cell. The binding of 125I-Man- BSA to keratinocytes proved to be time-dependent, acid-precipitable, and Ca2+- and trypsin-sensitive. After trypsinization the receptors underwent a rapid recovery at 37 degrees C. These results demonstrate the presence of mannose receptor on human keratinocytes, and its active involvement in the killing of Candida albicans.
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Affiliation(s)
- G Szolnoky
- Department of Dermatology, Albert Szent-Györgyi Medical Center, University of Szeged, Szeged, Hungary.
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15
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Cho MJ, Juliano R. Macromolecular versus small-molecule therapeutics: drug discovery, development and clinical considerations. Trends Biotechnol 1996; 14:153-8. [PMID: 8645449 DOI: 10.1016/0167-7799(96)10024-x] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Recent advances in biomedical science in general, and molecular biology in particular, have provided a greater understanding of pathogenesis at the molecular and (sub)cellular level. In turn, this has stimulated the development of macromolecular, mechanism-based therapeutic agents, ranging from recombinant proteins, to oligonucleotides, to genes/gene fragments. The factors essential for the successful development of this new class of therapeutic agents are not necessarily the same as those for the development of conventional small organic molecules. This review mentions several issues relating to the development of macromolecular drugs, and emphasizes the key issue of drug transport and delivery.
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Affiliation(s)
- M J Cho
- School of Pharmacy, University of North Carolina, Chapel Hill 27599, USA
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16
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Rudd PM, Woods RJ, Wormald MR, Opdenakker G, Downing AK, Campbell ID, Dwek RA. The effects of variable glycosylation on the functional activities of ribonuclease, plasminogen and tissue plasminogen activator. BIOCHIMICA ET BIOPHYSICA ACTA 1995; 1248:1-10. [PMID: 7711052 DOI: 10.1016/0167-4838(94)00230-e] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The relatively large size and dynamics of oligosaccharides can result in substantial shielding of functionally important areas of proteins to which they are attached, modulate the interactions of glycoconjugates with other molecules and affect the rate of processes which involve conformational changes. This review focuses on the occupancy of N-linked glycosylation sites on three enzymes, ribonuclease, plasminogen and tissue plasminogen activator. Each of these proteins occurs naturally as two populations of molecules, distinguished from each other only by the presence or absence of an oligosaccharide at one glycosylation site. The presence of an oligomannose sugar on ribonuclease (at Asn-34) alters its overall dynamics, increases its stability towards proteinases and decreases its functional activity towards double-stranded RNA. The N-linked sugar on plasminogen (at Asn-288) within kringle 3 reduces the rate of the beta- to alpha-conformational change, modulates the transport of plasminogen into the extravascular compartment, decreases plasminogen binding to U937 cells and downregulates the activation of plasminogen by both urokinase and tissue plasminogen activator. Additionally, in fibrinolysis, within a ternary complex of fibrin, plasminogen and tissue plasminogen activator, the N-linked sugar of plasminogen hinders the initial interaction with tissue plasminogen activator (i.e., it alters Km). The presence of an N-linked glycan (at Asn-184) in the kringle 2 domain of tissue plasminogen activator hinders the rearrangement of this ternary complex, decreasing the turnover rate (Kcat).
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Affiliation(s)
- P M Rudd
- Glycobiology Institute, Department of Biochemistry, Oxford, UK
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17
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Orth K, Willnow T, Herz J, Gething M, Sambrook J. Low density lipoprotein receptor-related protein is necessary for the internalization of both tissue-type plasminogen activator-inhibitor complexes and free tissue-type plasminogen activator. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)31937-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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18
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Andreasen PA, Sottrup-Jensen L, Kjøller L, Nykjaer A, Moestrup SK, Petersen CM, Gliemann J. Receptor-mediated endocytosis of plasminogen activators and activator/inhibitor complexes. FEBS Lett 1994; 338:239-45. [PMID: 8307187 DOI: 10.1016/0014-5793(94)80276-9] [Citation(s) in RCA: 117] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Recent findings have elucidated the mechanism for clearance from the extracellular space of the two types of plasminogen activators, urokinase-type plasminogen activator (u-PA) and tissue-type plasminogen activator (t-PA), and their type-1 inhibitor (PAI-1). Activator/PAI-1 complexes and uncomplexed t-PA bind to the multi-ligand receptors alpha 2-macroglobulin receptor/low density lipoprotein receptor-related protein (alpha 2MR) and epithelial glycoprotein 330 (gp330). These receptors mediate endocytosis and degradation of u-PA/PAI-1 complex bound to the glycosyl phosphatidyl inositol-anchored urokinase receptor (u-PAR) on cell surfaces, and participate, in cooperation with other receptors, in hepatic clearance of activator/PAI-1 complexes and uncomplexed t-PA from blood plasma. The alpha 2MR- and gp330-mediated endocytosis of a ligand (u-PA/PAI-1 complex) initially bound to another receptor (u-PAR) is a novel kind of interaction between membrane receptors. Binding to alpha 2MR and gp330 is a novel kind of molecular recognition of serine proteinases and serpins.
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Affiliation(s)
- P A Andreasen
- Department of Molecular Biology, University of Aarhus, Denmark
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19
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Affiliation(s)
- T Ny
- Department of Cell and Molecular Biology, University of Umeå, Sweden
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20
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Stockinger H, Kubbies M, Rudolph R, Stern A, Kohnert U, Fischer S. Binding of recombinant variants of human tissue-type plasminogen activator (t-PA) to human umbilical vein endothelial cells. Thromb Res 1992; 67:589-99. [PMID: 1333104 DOI: 10.1016/0049-3848(92)90019-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Endothelial cells synthesize and secrete hemostatic components like tissue-type plasminogen activator (t-PA) which is thought to be the major determinant of fibrinolytic activity in the blood. Most recently, a receptor protein for t-PA on human umbilical vein endothelial cells (HUVEC) in culture has been described (1); there are, however, in addition low affinity binding sites for t-PA on HUVEC. The sites of binding are of particular interest, because they are potential regulators of t-PA activity and clearance. We analysed the low affinity binding of recombinant t-PA (rt-PA) to normal diploid HUVEC and to the permanent human cell lines Jurkat, Daudi, HL 60 and K562 by flow cytometry applying t-PA specific monoclonal antibodies. Using this test system binding of both recombinant glycosylated human t-PA produced in Chinese hamster ovary cells (CHO-t-PA) and of nonglycosylated t-PA, produced in E. coli (BM 06.021) was investigated. Analysis of the binding pattern to HUVEC and other cell lines revealed that deglycosylation of full length rt-PA increases non-specific binding. Additionally, we investigated the binding properties of an unglycosylated t-PA deletion variant which comprises the kringle 2 and the protease domains (BM 06.022). Data obtained show that deletion of these domains most drastically reduces non-specific binding to HUVEC and other human cell lines.
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Affiliation(s)
- H Stockinger
- Boehringer Mannheim GmbH, Biochemical Research Center, Penzberg, Germany
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21
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Orth K, Madison EL, Gething MJ, Sambrook JF, Herz J. Complexes of tissue-type plasminogen activator and its serpin inhibitor plasminogen-activator inhibitor type 1 are internalized by means of the low density lipoprotein receptor-related protein/alpha 2-macroglobulin receptor. Proc Natl Acad Sci U S A 1992; 89:7422-6. [PMID: 1502153 PMCID: PMC49722 DOI: 10.1073/pnas.89.16.7422] [Citation(s) in RCA: 196] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Tissue-type plasminogen activator and urokinase are serine proteases secreted by many cell types that participate in biological processes, such as tissue restructuring, cell migration, and tumor metastasis. Clinically, these proteases are used to dissolve coronary fibrin clots that are the proximal causes of acute myocardial infarction. In vivo, the activity of these enzymes is controlled by plasminogen-activator inhibitors, members of the serpin family of protease inhibitors. This study shows that tissue-type plasminogen activator-inhibitor complexes bind in solution to low density lipoprotein receptor-related protein (LRP), a large heterodimeric ubiquitous membrane receptor. In cultured cells, endocytosis and degradation of these complexes is reduced by polyclonal antibodies directed against LRP and inhibited by a M(r) 39,000 protein that binds to LRP and inhibits its interaction with previously known ligands, including apolipoprotein E and alpha 2-macroglobulin. We propose a role for LRP in the clearance of plasminogen activator-inhibitor complexes that is analogous to its function in the endocytosis of alpha 2-macroglobulin-protease complexes.
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Affiliation(s)
- K Orth
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas 75235
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22
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Stang E, Roos N, Schlüter M, Berg T, Krause J. Evidence for carbohydrate-independent endocytosis of tissue-type plasminogen activator by liver cells. Biochem J 1992; 285 ( Pt 3):799-804. [PMID: 1323274 PMCID: PMC1132866 DOI: 10.1042/bj2850799] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In the liver, tissue-type plasminogen activator (t-PA) is endocytosed by hepatic parenchymal (PC), endothelial (EC) and Kupffer (KC) cells. Although the endocytosis is receptor-mediated, it remains a matter of discussion which receptors are involved in this catabolic process. To evaluate the role of a protein-specific receptor, as well as the possible involvement of the galactose receptor on PC and the mannose receptor on EC, we have employed different glycosylation variants of t-PA in biochemical and immunocytochemical studies. Partial or total removal of carbohydrate side-chains by endoglycosidases did not prevent clearance and hepatic endocytosis of t-PA by either of the liver cell types. Blockade of the galactose and mannose receptors by co-application of a large excess of the glycoprotein ovalbumin remained without effect on the binding and uptake of t-PA by hepatic cells. However, the contribution of different liver cell types to the hepatic clearance of t-PA was to a certain extent dependent on the type of oligosaccharide chains removed. The mannose receptor on EC is partially responsible for the clearance of t-PA by this cell type, whereas the galactose receptor does not seem to be involved in this process. The results obtained in this study further demonstrate that the major portion of the hepatic catabolism of t-PA is independent of its carbohydrate side-chains.
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Affiliation(s)
- E Stang
- Electronmicroscopical Unit for Biological Sciences, University of Oslo, Blindern, Norway
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23
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Otter M, Zocková P, Kuiper J, van Berkel TJ, Barrett-Bergshoeff MM, Rijken DC. Isolation and characterization of the mannose receptor from human liver potentially involved in the plasma clearance of tissue-type plasminogen activator. Hepatology 1992; 16:54-9. [PMID: 1618483 DOI: 10.1002/hep.1840160111] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Various studies have shown that mannose receptors rapidly eliminate glycoproteins and microorganisms bearing high mannose-type carbohydrate chains from the blood circulation. The purpose of this study was to characterize the mannose receptor in the liver, which in vivo is involved in the rapid clearance of tissue-type plasminogen activator from the circulation. Human liver membranes were solubilized in Triton X-100, and the solution was applied to a tissue-type plasminogen activator Sepharose column. Bound proteins were eluted with ethylenediaminetetraacetate (10 mmol/L). A second, similar purification step rendered a single liver protein of 175,000 daltons. A combination of ligand blotting and a chromogenic assay for tissue-type plasminogen activator demonstrated that the identified liver protein is a mannose receptor because it bound tissue-type plasminogen activator, this tissue-type plasminogen activator binding being fully inhibited by 0.2 mol/L D-mannose. Western-blot analysis revealed that the isolated liver protein is immunologically identical to the human mannose receptor from placenta. Treatment of the liver protein and the placenta mannose receptor with trypsin yielded the same pattern of proteolytic degradation products as identified on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. We conclude that the physiologically relevant mannose receptor for tissue-type plasminogen activator clearance isolated from human liver is immunologically and structurally similar to or identical with the human mannose receptor isolated from placenta.
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Affiliation(s)
- M Otter
- Gaubius Laboratory, TNO Institute of Ageing and Vascular Research, Leiden, The Netherlands
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24
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Martin U, Fischer S, Kohnert U, Opitz U, Rudolph R, Sponer G, Stern A, Strein K. Pharmacokinetic and thrombolytic properties of unglycosylated recombinant tissue-type plasminogen activator (BM 06.021) produced in Escherichia coli. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1992; 346:108-13. [PMID: 1407000 DOI: 10.1007/bf00167579] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Recombinant tissue-type plasminogen activator (rt-PA) was produced in Escherichia coli cells in order to obtain an unglycosylated rt-PA (BM 06.021) with increased thrombolytic potency due to altered pharmacokinetic properties. The pharmacokinetics were studied in rabbits upon intravenous infusion of 200 kU/kg over 30 min. The thrombolytic dose-response effects were evaluated in a rabbit model with 125I-labeled venous thrombi upon intravenous infusion over 4 h. The thrombolytic effects after intravenous bolus injection of 200 kU/kg BM 06.021 were investigated in a canine model of coronary artery thrombosis. All studies were performed comparing BM 06.021 with glycosylated rt-PA (alteplase). BM 06.021 demonstrated a longer (p less than 0.05) half-life (5.6 +/- 2.6 vs. 2.1 +/- 0.3 min) and a lower (p less than 0.05) clearance rate (7.5 +/- 0.8 vs. 22.2 +/- 3.1 ml.min-1.kg-1) than alteplase in rabbits upon intravenous infusion. The dose-response curve of BM 06.021 for thrombolysis in a rabbit model of jugular vein thrombosis was located to the left of that for alteplase with a 2.1-fold lower effective dose of 50% thrombolysis (ED50) of BM 06.021 (207 vs. 436 kU/kg). Intravenous bolus injection of 200 kU/kg BM 06.021 induced the same reperfusion rate (4/6) as intravenous infusion of 800 kU/kg alteplase over 90 min in a canine model of coronary artery thrombosis. The residual thrombus wet weight did not significantly differ between BM 06.021 and alteplase (5.7 +/- 1.8 vs. 6.3 +/- 1.1 mg). The results indicate that unglycosylated rt-PA (BM 06.021) has a higher in vivo thrombolytic potency than glycosylated rt-PA (alteplase).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- U Martin
- Department of Pharmacology, Boehringer Mannheim GmbH, Federal Republic of Germany
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25
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Otter M, Kuiper J, Bos R, Rijken DC, van Berkel TJ. Characterization of the interaction both in vitro and in vivo of tissue-type plasminogen activator (t-PA) with rat liver cells. Effects of monoclonal antibodies to t-PA. Biochem J 1992; 284 ( Pt 2):545-50. [PMID: 1318035 PMCID: PMC1132672 DOI: 10.1042/bj2840545] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The interaction of 125I-labelled tissue-type plasminogen activator (125I-t-PA) with freshly isolated rat parenchymal and endothelial liver cells was studied. Binding experiments at 4 degrees C with parenchymal cells and endothelial liver cells indicated the presence of 68,000 and 44,000 high-affinity t-PA-binding sites, with an apparent Kd of 3.5 and 4 nM respectively. Association of 125I-t-PA with parenchymal cells was Ca(2+)-dependent and was not influenced by asialofetuin, a known ligand for the galactose receptor. Association of 125I-t-PA with liver endothelial cells was Ca(2+)-dependent and mannose-specific, since ovalbumin (a mannose-terminated glycoprotein) inhibited the cell association of t-PA. Association of 125I-t-PA with liver endothelial cells was inhibited by anti-(human mannose receptor) antiserum. Anti-(galactose receptor) IgG had no effect on 125I-t-PA association with either cell type. Degradation of 125I-t-PA at 37 degrees C by both cell types was inhibited by chloroquine or NH4Cl, indicating that t-PA is degraded lysosomally. in vitro experiments with three monoclonal antibodies (MAbs) demonstrated that anti-t-PA MAb 1-3-1 specifically decreased association of 125I-t-PA with the endothelial cells, and anti-t-PA Mab 7-8-4 inhibited association with the parenchymal cells. Results of competition experiments in rats in vivo with these antibodies were in agreement with findings in vitro. Both antibodies decreased the liver uptake of 125I-t-PA, while a combination of the two antibodies was even more effective in reducing the liver association of 125I-t-PA and increasing its plasma half-life. We conclude from these data that clearance of t-PA by the liver is regulated by at least two pathways, one on parenchymal cells (not galactose/mannose-mediated) and another on liver endothelial cells (mediated by a mannose receptor). Results with the MAbs imply that two distinct sites on the t-PA molecule are involved in binding to parenchymal cells and liver endothelial cells.
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Affiliation(s)
- M Otter
- Gaubius Laboratory IVVO-TNO, Leiden, The Netherlands
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26
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Bassel-Duby R, Jiang N, Bittick T, Madison E, McGookey D, Orth K, Shohet R, Sambrook J, Gething M. Tyrosine 67 in the epidermal growth factor-like domain of tissue-type plasminogen activator is important for clearance by a specific hepatic receptor. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(19)50142-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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27
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Stang E, Krause J, Seydel W, Berg T, Roos N. Endocytosis and intracellular processing of tissue-type plasminogen activator by rat liver cells in vivo. Biochem J 1992; 282 ( Pt 3):841-51. [PMID: 1554369 PMCID: PMC1130864 DOI: 10.1042/bj2820841] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Endocytosis of tissue-type plasminogen activator (t-PA) by different types of rat liver cells was studied in immunocytochemically labelled cryosections as well as in biochemical experiments. For morphological localization of the ligand in different endocytic compartments involved in its catabolism, rat livers were fixed at various times (1-24 min) after injection of t-PA. Late-endosomal and lysosomal compartments were identified by double-labelling the sections with antibodies to the lysosomal proteins glycoprotein Igp 120 and cathepsin D. In liver t-PA was localized in sinusoidal endothelial cells (EC), parenchymal cells (PC) and to some extent in Kupffer cells (KC), indicating that it is internalized and degraded in all three cell types. In specimens fixed 6 min after injection PC, EC and KC were found to contribute to 69, 24 and 7% respectively of total t-PA endocytosed. The transfer from late endosomes to lysosomes was found to be faster in EC than in PC. The morphological findings were supported by studies of the endocytic mechanisms employing isolated perfused livers and primary hepatocytes. The presence of monensin, an inhibitor of lysosomal protein degradation, reduced the amount of t-PA degraded to about 50% of the control values. The catalytic site seems not to be required for the catabolism of t-PA in hepatic cells. The inhibition of t-PA by D-phenylalanyl-L-prolylarginyl-chloromethane did not influence receptor recognition and catabolic processing, as determined in morphological studies using labelled cryosections, in binding studies employing liver cell membranes and primary hepatocytes, as well as in liver-perfusion experiments.
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Affiliation(s)
- E Stang
- Department of Biology, University of Oslo, Norway
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28
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Martin U, Köhler J, Sponer G, Strein K. Pharmacokinetics of the novel recombinant plasminogen activator BM 06.022 in rats, dogs, and non-human primates. ACTA ACUST UNITED AC 1992. [DOI: 10.1016/0268-9499(92)90046-k] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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29
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Goochee CF, Gramer MJ, Andersen DC, Bahr JB, Rasmussen JR. The Oligosaccharides of Glycoproteins: Bioprocess Factors Affecting Oligosaccharide Structure and their Effect on Glycoprotein Properties. ACTA ACUST UNITED AC 1991; 9:1347-55. [PMID: 1367768 DOI: 10.1038/nbt1291-1347] [Citation(s) in RCA: 234] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In this review, we organize the recent data concerning the effects of bioprocess factors on the oligosaccharide structure of human therapeutic glycoproteins, with particular emphasis on the influence of the host cell. We also discuss the effect of oligosaccharide structure on glycoprotein properties, including antigenicity, immunogenicity and plasma clearance rate.
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Affiliation(s)
- C F Goochee
- Department of Chemical Engineering, Stanford University, CA 94305-5025
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30
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Affiliation(s)
- J D Vassalli
- Department of Morphology, University of Geneva Medical School, Switzerland
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31
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Martin U, Fischer S, Kohnert U, Rudolph R, Sponer G, Stern A, Strein K. Pharmacokinetic properties of an Escherichia-coli-produced recombinant plasminogen activator (BM 06.022) in rabbits. Thromb Res 1991; 62:137-46. [PMID: 1909815 DOI: 10.1016/0049-3848(91)90188-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The recombinant plasminogen activator BM 06.022 consists of the kringle 2 and the protease domains of human t-PA and is unglycosylated because of its expression in Escherichia coli. The pharmacokinetic properties of BM 06.022 following intravenous injection over 1 min were characterized in anesthetized male New Zealand white rabbits. BM 06.022 was injected at doses of 50, 100, 200, and 400 kU/kg bw (n = 5-6/dose). Activity concentrations in plasma were determined using an indirect spectrophotometric assay. The maximum plasma concentration and the area under the plasma concentration vs. time curve (AUC0-00) of BM 06.022 increased linearly with dose. The systemic clearance ranged from 2.5 to 3.0 ml.min-1.kg-1 and did not show dose-dependency, in contrast to alteplase which was studied at doses of 200, 400, 800, and 1600 kU/kg. A direct comparison of clearance rates of BM 06.022 and alteplase at doses of 200 and 400 kU/kg each revealed a 8.5-fold slower clearance rate of BM 06.022. The majority (18/23) of rabbits with BM 06.022 injection showed a pharmacokinetic profile which was best characterized by a one-compartment model in contrast to alteplase (10/23). The dose-groups of BM 06.022 showed an average dominant half-life ranging from 11.6 to 15.4 min, which was about five-times longer than the dominant half-life values of alteplase (2.3 to 4.5 min). Assuming a two-compartment model in the remaining animals, the initial alpha-phase of BM 06.022 accounted for 40.1 +/- 13.2% (n = 5) of the total AUC, whereas the alpha-phase of alteplase accounted for 82.7 +/- 3% (n = 13) of the total AUC.
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Affiliation(s)
- U Martin
- Department of Pharmacology, Boehringer Mannheim GmbH, Germany
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32
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Wing LR, Bennett B, Booth NA. The receptor for tissue plasminogen activator (t-PA) in complex with its inhibitor, PAI-1, on human hepatocytes. FEBS Lett 1991; 278:95-7. [PMID: 1847116 DOI: 10.1016/0014-5793(91)80092-h] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The binding of t-PA-PAI-1 to human hepatocytes at 4 degrees C reached a maximum at 2 h. Scatchard analysis indicated 74,000 +/- 11,000 high-affinity binding sites for complex per human hepatocyte, with a Kd of 0.87 +/- 0.09 nM. Almost identical results were achieved with the human hepatoma cell line Hep G2. Binding of [125I]t-PA-PAI-1 complex was unaffected by high concentrations of unlabelled t-PA, PAI-1, u-PA or u-PA-PAI-1 complex; only t-PA-PAI-1 complex competed for binding. Hepatocyte-bound t-PA-PAI-1 was internalized and degraded at 37 degrees C. Thus, hepatocytes have a specific t-PA-PAI-1 receptor that participates in clearance of this complex.
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Affiliation(s)
- L R Wing
- Department of Molecular & Cell Biology, University of Aberdeen, Scotland, UK
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