Novel Thrombolytic Drug Based on Thrombin Cleavable Microplasminogen Coupled to a Single-Chain Antibody Specific for Activated GPIIb/IIIa

Thomas Bonnard, Zachary Tennant, BeEri Niego, Ruchi Kanojia, Karen Alt, Shweta Jagdale, Lok Soon Law, Sheena Rigby, Robert Lindsay Medcalf, Karlheinz Peter, Christoph Eugen Hagemeyer

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Background Thrombolytic therapy for acute thrombosis is limited by life-threatening side effects such as major bleeding and neurotoxicity. New treatment options with enhanced fibrinolytic potential are therefore required. Here, we report the development of a new thrombolytic molecule that exploits key features of thrombosis. We designed a recombinant microplasminogen modified to be activated by the prothrombotic serine-protease thrombin (HtPlg), fused to an activation-specific antitextendashglycoprotein IIb/IIIa single-chain antibody (SCE5), thereby hijacking the coagulation system to initiate thrombolysis.Methods and Results The resulting fusion protein named SCE5-HtPlg shows in~vitro targeting towards the highly abundant activated form of the fibrinogen receptor glycoprotein IIb/IIIa expressed on activated human platelets. Following thrombin formation, SCE5-HtPlg is activated to contain active microplasmin. We evaluate the effectiveness of our targeted thrombolytic construct in two models of thromboembolic disease. Administration of SCE5-HtPlg (4~μg/g body weight) resulted in effective thrombolysis 20~minutes after injection in a ferric chloridetextendashinduced model of mesenteric thrombosis (48textpm3% versus 92textpm5% for saline control, Plt;0.01) and also reduced emboli formation in a model of pulmonary embolism (Plt;0.01 versus saline). Furthermore, at these effective therapeutic doses, the SCE5-HtPlg did not prolong bleeding time compared with saline (P=0.99).Conclusions Our novel fusion molecule is a potent and effective treatment for thrombosis that enables in~vivo thrombolysis without bleeding time prolongation. The activation of this construct by thrombin generated within the clot itself rather than by a plasminogen activator, which needs to be delivered systemically, provides a novel targeted approach to improve thrombolysis.
Original languageEnglish
Article numbere004535
JournalAmerican Heart Association. Journal. Cardiovascular and Cerebrovascular Disease
Volume6
Issue number2
DOIs
Publication statusPublished - 3 Feb 2017

Cite this

@article{85fbaec858da448ea25d28ba9672301e,
title = "Novel Thrombolytic Drug Based on Thrombin Cleavable Microplasminogen Coupled to a Single-Chain Antibody Specific for Activated GPIIb/IIIa",
abstract = "Background Thrombolytic therapy for acute thrombosis is limited by life-threatening side effects such as major bleeding and neurotoxicity. New treatment options with enhanced fibrinolytic potential are therefore required. Here, we report the development of a new thrombolytic molecule that exploits key features of thrombosis. We designed a recombinant microplasminogen modified to be activated by the prothrombotic serine-protease thrombin (HtPlg), fused to an activation-specific antitextendashglycoprotein IIb/IIIa single-chain antibody (SCE5), thereby hijacking the coagulation system to initiate thrombolysis.Methods and Results The resulting fusion protein named SCE5-HtPlg shows in~vitro targeting towards the highly abundant activated form of the fibrinogen receptor glycoprotein IIb/IIIa expressed on activated human platelets. Following thrombin formation, SCE5-HtPlg is activated to contain active microplasmin. We evaluate the effectiveness of our targeted thrombolytic construct in two models of thromboembolic disease. Administration of SCE5-HtPlg (4~μg/g body weight) resulted in effective thrombolysis 20~minutes after injection in a ferric chloridetextendashinduced model of mesenteric thrombosis (48textpm3{\%} versus 92textpm5{\%} for saline control, Plt;0.01) and also reduced emboli formation in a model of pulmonary embolism (Plt;0.01 versus saline). Furthermore, at these effective therapeutic doses, the SCE5-HtPlg did not prolong bleeding time compared with saline (P=0.99).Conclusions Our novel fusion molecule is a potent and effective treatment for thrombosis that enables in~vivo thrombolysis without bleeding time prolongation. The activation of this construct by thrombin generated within the clot itself rather than by a plasminogen activator, which needs to be delivered systemically, provides a novel targeted approach to improve thrombolysis.",
author = "Thomas Bonnard and Zachary Tennant and BeEri Niego and Ruchi Kanojia and Karen Alt and Shweta Jagdale and Law, {Lok Soon} and Sheena Rigby and Medcalf, {Robert Lindsay} and Karlheinz Peter and Hagemeyer, {Christoph Eugen}",
year = "2017",
month = "2",
day = "3",
doi = "10.1161/JAHA.116.004535",
language = "English",
volume = "6",
journal = "American Heart Association. Journal. Cardiovascular and Cerebrovascular Disease",
issn = "2047-9980",
publisher = "American Heart Association, Inc.",
number = "2",

}

Novel Thrombolytic Drug Based on Thrombin Cleavable Microplasminogen Coupled to a Single-Chain Antibody Specific for Activated GPIIb/IIIa. / Bonnard, Thomas; Tennant, Zachary; Niego, BeEri; Kanojia, Ruchi; Alt, Karen; Jagdale, Shweta; Law, Lok Soon; Rigby, Sheena; Medcalf, Robert Lindsay; Peter, Karlheinz; Hagemeyer, Christoph Eugen.

In: American Heart Association. Journal. Cardiovascular and Cerebrovascular Disease, Vol. 6, No. 2, e004535, 03.02.2017.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Novel Thrombolytic Drug Based on Thrombin Cleavable Microplasminogen Coupled to a Single-Chain Antibody Specific for Activated GPIIb/IIIa

AU - Bonnard, Thomas

AU - Tennant, Zachary

AU - Niego, BeEri

AU - Kanojia, Ruchi

AU - Alt, Karen

AU - Jagdale, Shweta

AU - Law, Lok Soon

AU - Rigby, Sheena

AU - Medcalf, Robert Lindsay

AU - Peter, Karlheinz

AU - Hagemeyer, Christoph Eugen

PY - 2017/2/3

Y1 - 2017/2/3

N2 - Background Thrombolytic therapy for acute thrombosis is limited by life-threatening side effects such as major bleeding and neurotoxicity. New treatment options with enhanced fibrinolytic potential are therefore required. Here, we report the development of a new thrombolytic molecule that exploits key features of thrombosis. We designed a recombinant microplasminogen modified to be activated by the prothrombotic serine-protease thrombin (HtPlg), fused to an activation-specific antitextendashglycoprotein IIb/IIIa single-chain antibody (SCE5), thereby hijacking the coagulation system to initiate thrombolysis.Methods and Results The resulting fusion protein named SCE5-HtPlg shows in~vitro targeting towards the highly abundant activated form of the fibrinogen receptor glycoprotein IIb/IIIa expressed on activated human platelets. Following thrombin formation, SCE5-HtPlg is activated to contain active microplasmin. We evaluate the effectiveness of our targeted thrombolytic construct in two models of thromboembolic disease. Administration of SCE5-HtPlg (4~μg/g body weight) resulted in effective thrombolysis 20~minutes after injection in a ferric chloridetextendashinduced model of mesenteric thrombosis (48textpm3% versus 92textpm5% for saline control, Plt;0.01) and also reduced emboli formation in a model of pulmonary embolism (Plt;0.01 versus saline). Furthermore, at these effective therapeutic doses, the SCE5-HtPlg did not prolong bleeding time compared with saline (P=0.99).Conclusions Our novel fusion molecule is a potent and effective treatment for thrombosis that enables in~vivo thrombolysis without bleeding time prolongation. The activation of this construct by thrombin generated within the clot itself rather than by a plasminogen activator, which needs to be delivered systemically, provides a novel targeted approach to improve thrombolysis.

AB - Background Thrombolytic therapy for acute thrombosis is limited by life-threatening side effects such as major bleeding and neurotoxicity. New treatment options with enhanced fibrinolytic potential are therefore required. Here, we report the development of a new thrombolytic molecule that exploits key features of thrombosis. We designed a recombinant microplasminogen modified to be activated by the prothrombotic serine-protease thrombin (HtPlg), fused to an activation-specific antitextendashglycoprotein IIb/IIIa single-chain antibody (SCE5), thereby hijacking the coagulation system to initiate thrombolysis.Methods and Results The resulting fusion protein named SCE5-HtPlg shows in~vitro targeting towards the highly abundant activated form of the fibrinogen receptor glycoprotein IIb/IIIa expressed on activated human platelets. Following thrombin formation, SCE5-HtPlg is activated to contain active microplasmin. We evaluate the effectiveness of our targeted thrombolytic construct in two models of thromboembolic disease. Administration of SCE5-HtPlg (4~μg/g body weight) resulted in effective thrombolysis 20~minutes after injection in a ferric chloridetextendashinduced model of mesenteric thrombosis (48textpm3% versus 92textpm5% for saline control, Plt;0.01) and also reduced emboli formation in a model of pulmonary embolism (Plt;0.01 versus saline). Furthermore, at these effective therapeutic doses, the SCE5-HtPlg did not prolong bleeding time compared with saline (P=0.99).Conclusions Our novel fusion molecule is a potent and effective treatment for thrombosis that enables in~vivo thrombolysis without bleeding time prolongation. The activation of this construct by thrombin generated within the clot itself rather than by a plasminogen activator, which needs to be delivered systemically, provides a novel targeted approach to improve thrombolysis.

U2 - 10.1161/JAHA.116.004535

DO - 10.1161/JAHA.116.004535

M3 - Article

VL - 6

JO - American Heart Association. Journal. Cardiovascular and Cerebrovascular Disease

JF - American Heart Association. Journal. Cardiovascular and Cerebrovascular Disease

SN - 2047-9980

IS - 2

M1 - e004535

ER -