Thromb Haemost 1997; 77(04): 796-803
DOI: 10.1055/s-0038-1656052
Animal Models
Schattauer GmbH Stuttgart

Recombinant Polypeptides Derived from the Fibrin Binding Domain of Fibronectin Are Potential Agents for the Imaging of Blood Clots

Authors

  • N Ezov

    Bio-Technology General, Rehovot, Israel
  • A Nimrod

    Bio-Technology General, Rehovot, Israel
  • B Parizada

    Bio-Technology General, Rehovot, Israel
  • M M Werber

    Bio-Technology General, Rehovot, Israel
  • A Goldlust

    Bio-Technology General, Rehovot, Israel
  • L A Greenstein

    Bio-Technology General, Rehovot, Israel
  • T Vogel

    Bio-Technology General, Rehovot, Israel
  • N Drizlich

    Bio-Technology General, Rehovot, Israel
  • A Levanon

    Bio-Technology General, Rehovot, Israel
  • S Reich

    Bio-Technology General, Rehovot, Israel
  • M Gorecki

    Bio-Technology General, Rehovot, Israel
  • A Panet

    Bio-Technology General, Rehovot, Israel
Weitere Informationen

Publikationsverlauf

Received 09. September 1996

Accepted after resubmission 03. Dezember 1996

Publikationsdatum:
26. Juli 2018 (online)

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Summary

Thrombus formation in the circulation is accompanied by covalent linkage of fibronectin (FN) through transglutamination of glutamine no. 3 in the fibrin binding amino terminal domain (FBD) of FN. We have exploited this phenomenon for thrombus detection by the employment of radioactively-labelled recombinant polypeptide molecules derived from the 5-finger FBD of human FN. Three recombinant FBD polypeptides, 12 kDa (“2 fingers”), 18.5 kDa (“3 fingers”) and 31 kDa FBD (“5 fingers”), were prepared and compared to native FN-derived 31 kDa-FBD with respect to their ability to attach to fibrin clots in vitro and in vivo. The accessibility of Gln-3 in these molecules was demonstrated by the incorporation of stoichiometric amounts of 14C- putrescine in the presence of plasma transglutaminase. Competitive binding experiments to fibrin have indicated that, although the binding affinities of the FBD molecules are lower than that of FN, substantial covalent linkage was obtained in the presence of transglutaminase, and even in the presence of excess FN or heparin. The biological clearance rates of radioactively labelled FBD molecules in rats and rabbits were much higher than those of FN and fibrinogen, thus indicating their potential advantage for use as a diagnostic imaging tool. Of the three molecules, the 12 kDa FBD exhibited the highest rate of clearance. The potential of the 12 kDa and 31 kDa FBDs as imaging agents was examined in a stainless steel coil-induced thrombus model in rats and in a jugular vein thrombus model in rabbits, using either [125I] or [111ln]-labelled materials. At 24 h, clot-to-blood ratios ranged between 10 and 22 for [125I]-12 kDa FBD and 40 and 60 for [luIn]-12 kDa FBD. In the rat model, heparin did not inhibit the uptake of FBD. Taken together, the results indicate that recombinant 12 kDa FBD is a good candidate for the diagnosis of venous thrombosis.