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Thromb Haemost 1999; 82(02): 277-282
DOI: 10.1055/s-0037-1615843
Research Article
Schattauer GmbH

Structural Studies of Fibrinolysis by Electron and Light Microscopy

John W. Weisel
1   Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
,
Yuri Veklich
1   Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
,
Jean-Philippe Collet
1   Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
2   Service de Cardiologie, Assistance Hopitaux Publique de Paris, Paris, FRANCE
,
Charles W. Francis
3   Vascular Medicine Unit, Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
› Author Affiliations
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Publication History

Publication Date:
09 December 2017 (online)

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Introduction

Much is known about the fibrinolytic system that converts fibrin-bound plasminogen to the active protease, plasmin, using plasminogen activators, such as tissue-type plasminogen activator (t-PA) and urokinase-type plasminogen activator. Plasmin then cleaves fibrin at specific sites and generates soluble fragments, many of which have been characterized, providing the basis for a molecular model of the polypeptide chain degradation.1-3 Soluble degradation products of fibrin have also been characterized by transmission electron microscopy, yielding a model for their structure.4 Moreover, high resolution, three-dimensional structures of certain fibrinogen fragments has provided a wealth of information that may be useful in understanding how various proteins bind to fibrin and the overall process of fibrinolysis (Doolittle, this volume).5,6

Both the rate of fibrinolysis and the structures of soluble derivatives are determined in part by the fibrin network structure itself. Furthermore, the activation of plasminogen by t-PA is accelerated by the conversion of fibrinogen to fibrin, and this reaction is also affected by the structure of the fibrin. For example, clots made of thin fibers have a decreased rate of conversion of plasminogen to plasmin by t-PA, and they generally are lysed more slowly than clots composed of thick fibers.7-9 Under other conditions, however, clots made of thin fibers may be lysed more rapidly.10 In addition, fibrin clots composed of abnormally thin fibers formed from certain dysfibrinogens display decreased plasminogen binding and a lower rate of fibrinolysis.11-13 Therefore, our increasing knowledge of various dysfibrinogenemias will aid our understanding of mechanisms of fibrinolysis (Matsuda, this volume).14,15

To account for these diverse observations and more fully understand the molecular basis of fibrinolysis, more knowledge of the physical changes in the fibrin matrix that precede solubilization is required. In this report, we summarize recent experiments utilizing transmission and scanning electron microscopy and confocal light microscopy to provide information about the structural changes occurring in polymerized fibrin during fibrinolysis. Many of the results of these experiments were unexpected and suggest some aspects of potential molecular mechanisms of fibrinolysis, which will also be described here.

 

  • References

  • 1 Francis CW, Marder VJ, Barlow GH. Plasmic degradation of crosslinked fibrin. Characterization of new macromolecular soluble complexes and a model of their structure. J Clin Invest. 1980; 66: 1033-1043.
    CrossrefPubMedSearch in Google Scholar
  • 2 Francis CW, Marder VJ. A molecular model of plasmic degradation of crosslinked fibrin. Semin Thromb Hemost. 1982; 8: 25-35.
    Thieme ConnectPubMedSearch in Google Scholar
  • 3 Hantgan RR, Francis CW, Marder VJ. Fibrinogen structure and physiology. In: Colman RW, Hirsh J, Marder VJ, Salzman EW. eds. Hemostasis and Thrombosis: Basic Principles and Clinical Practice. 3rd ed.. Philadelphia: J.B. Lippincott; 1994: 277-300.
    Search in Google Scholar
  • 4 Weisel JW, Francis CW, Nagaswami C, Marder VJ. Determination of the topology of factor XIIIa-induced fibrin gamma-chain cross-links by electron microscopy of ligated fragments. J Biol Chem. 1993; 268: 26618-26624.
    PubMedSearch in Google Scholar
  • 5 Spraggon G, Everse SJ, Doolittle RF. Crystal structures of fragment D from human fibrinogen and its crosslinked counterpart from fibrin. Nature 1997; 389: 455-462.
    CrossrefPubMedSearch in Google Scholar
  • 6 Yee VC, Pratt KP, Cote HC, Trong IL, Chung DW, Davie EW, Stenkamp RE, Teller DC. Crystal structure of a 30 kDa C-terminal fragment from the gamma chain of human fibrinogen. Structure. 1997; 5: 125-138.
    CrossrefPubMedSearch in Google Scholar
  • 7 Gabriel DA, Muga K, Boothroyd EM. The effect of fibrin structure on fibrinolysis. J Biol Chem. 1992; 267: 24259-24263.
    PubMedSearch in Google Scholar
  • 8 Carr ME, Alving BM. Effect of fibrin structure on plasmin-mediated dissolution of plasma clots. Blood Coagul Fibrinolysis. 1995; 6: 567-573.
    CrossrefPubMedSearch in Google Scholar
  • 9 Williams S, Fatah K, Ivert T, Blombäck M. The effect of acetylsalicylic acid on fibrin gel lysis by tissue plasminogen activator. Blood Coagul Fibrinolysis. 1995; 6: 718-725.
    CrossrefPubMedSearch in Google Scholar
  • 10 Kolev K, Tenekedjiev K, Komorowicz E, Machovich R. Functional evaluation of the structural features of proteases and their substrate in fibrin surface degradation. J Biol Chem. 1997; 272: 13666-13675.
    CrossrefPubMedSearch in Google Scholar
  • 11 Collet JP, Soria J, Mirshahi M, Hirsch M, Dagonnet FB, Caen J, Soria C. Dusart syndrome. A new concept of the relationship between fibrin clot architecture and fibrin clot degradability: Hypofibrinolysis related to an abnormal clot structure. Blood 1993; 82: 2462-2469.
    CrossrefPubMedSearch in Google Scholar
  • 12 Collet J-P, Woodhead JL, Soria J, Soria C, Mirshahi M, Caen JP, Weisel JW. Fibrinogen Dusart: Electron microscopy of molecules, fibers and clots and viscoelastic measurements. Biophys J. 1996; 70: 500-510.
    CrossrefPubMedSearch in Google Scholar
  • 13 Wada Y, Lord ST. A correlation between thrombotic disease and a specific fibrinogen abnormality (A alpha 554 Arg —> Cys) in two unrelated kindred, Dusart and Chapel Hill III. Blood 1994; 84: 3709-3714.
    CrossrefPubMedSearch in Google Scholar
  • 14 Matsuda M. The structure-function relationship of hereditary dysfibrinogens. Int J Hematol. 1996; 64: 167-179.
    CrossrefPubMedSearch in Google Scholar
  • 15 Cote HC, Lord ST, Pratt KP. Gamma-Chain dysfibrinogenemias: Molecular structure-function relationships of naturally occurring mutations in the gamma chain of human fibrinogen. Blood 1998; 92: 2195-2212.
    PubMedSearch in Google Scholar
  • 16 Marder VJ, Francis CW. Plasmin degradation of cross-linked fibrin. Ann NY Acad Sci. 1982; 408: 397-406.
    PubMedSearch in Google Scholar
  • 17 Sakharov DV, Rijken DC. Superficial accumulation of plasminogen during plasma clot lysis. Circulation. 1995; 92: 1883-1890.
    CrossrefPubMedSearch in Google Scholar
  • 18 Sakharov DV, Nagelkerke JF, Rijken DC. Rearrangements of the fibrin network and spatial distribution of fibrinolytic components during plasma clot lysis. Study with confocal microscopy. J Biol Chem. 1996; 271: 2133-2138.
    CrossrefPubMedSearch in Google Scholar
  • 19 Braaten JV, Handt S, Jerome WG, Kirkpatrick J, Lewis JC, Hantgan RR. Regulation of fibrinolysis by platelet-released plasminogen activator inhibitor 1: Light scattering and ultrastructural examination of lysis of a model platelet-fibrin thrombus. Blood 1993; 81: 1290-1299.
    PubMedSearch in Google Scholar
  • 20 Diamond SL, Anand S. Inner clot diffusion and permeation during fibrinolysis. Biophys J. 1993; 65: 2622-2643.
    CrossrefPubMedSearch in Google Scholar
  • 21 Veklich Y, Francis CW, White J, Weisel JW. Structural studies of fibrinolysis by electron microscopy. Blood 1998; 92: 4721-4729.
    PubMedSearch in Google Scholar
  • 22 Weisel JW. Fibrin assembly. Lateral aggregation and the role of the two pairs of fibrinopeptides. Biophys J. 1986; 50: 1079-1093.
    CrossrefPubMedSearch in Google Scholar
  • 23 Shen LL, McDonagh RP, McDonagh J, Hermans J. Early events in the plasmin digestion of fibrinogen and fibrin. Effects of plasmin on fibrin polymerization. J Biol Chem. 1977; 252: 6184-6189.
    PubMedSearch in Google Scholar
  • 24 Weisel JW, Nagaswami C, Korsholm B, Petersen LC, Suenson E. Interactions of plasminogen and polymerizing fibrin and its derivatives monitored with a photoaffinity cross-linker and electron microscopy. J Mol Biol. 1994; 235: 1117-1135.
    CrossrefPubMedSearch in Google Scholar
  • 25 Blinc A, Planinsic G, Keber D, Jarh O, Lahajnar G, Zidansek A, Demsar F. Dependence of blood clot lysis on the mode of transport of urokinase into the clot—A magnetic resonance imaging study in vitro. Thromb Haemost. 1991; 65: 549-552.
    Thieme ConnectPubMedSearch in Google Scholar
  • 26 Hantgan R, Fowler W, Erickson H, Hermans J. Fibrin assembly: A comparison of electron microscopic and light scattering results. Thromb Haemost. 1980; 44: 119-124.
    Thieme ConnectPubMedSearch in Google Scholar
  • 27 Hantgan RR, Hermans J. Assembly of fibrin. A light scattering study. J Biol Chem. 1979; 254: 11272-11281.
    PubMedSearch in Google Scholar
  • 28 Weisel JW, Nagaswami C. Computer modeling of fibrin polymerization kinetics correlated with electron microscope and turbidity observations: Clot structure and assembly are kinetically controlled. Biophys J. 1992; 63: 111-128.
    CrossrefPubMedSearch in Google Scholar
  • 29 Francis CW, Marder VJ. Rapid formation of large molecular weight alpha-polymers in cross-linked fibrin induced by high factor XIII concentrations. J Clin Invest. 1987; 80: 1459-1465.
    CrossrefPubMedSearch in Google Scholar
  • 30 Suenson E, Lützen O, Thorsen S. Initial plasmin-degradation of fibrin as the basis of a positive feedback mechanism in fibrinolysis. Eur J Biochem. 1984; 149: 193-200.
    PubMedSearch in Google Scholar
  • 31 Christensen U, Mølgaard L. Positive co-operative binding at two weak lysine-binding sites governs the Glu-plasminogen conformational change. Biochem J. 1992; 285: 419-425.
    CrossrefPubMedSearch in Google Scholar
  • 32 Marshall JM, Brown AJ, Ponting CP. Conformational studies of human plasminogen and plasminogen fragments: evidence for a novel third conformation of plasminogen. Biochemistry. 1994; 33: 3599-3606.
    CrossrefPubMedSearch in Google Scholar
  • 33 Ponting CP, Marshall JM, Cederholm-Williams SA. Plasminogen: A structural review. Blood Coagul Fibrinolysis. 1992; 3: 605-614.
    CrossrefPubMedSearch in Google Scholar
  • 34 Garman AJ, Smith RAG. The binding of plasminogen to fibrin: Evidence for plasminogen-bridging. Thromb Res. 1982; 27: 311-320.
    CrossrefPubMedSearch in Google Scholar
  • 35 Petersen LC, Suenson E. Effect of plasminogen and tissue-type plasminogen activator on fibrin gel structure. Fibrinolysis. 1991; 5: 51-59.
    PubMedSearch in Google Scholar