Collagen-Induced Platelet Aggregation Inhibitor from Mosquito Salivary Glands

Exposed collagen in injured blood vessels provides a substrate for platelets to adhere and aggregate initiating the first step in thrombosis, the formation of blood clots inside a blood vessel. Despite the essential role of platelets in vascular injury, excessive platelet aggregation may also result in thrombotic diseases such as stroke and heart attack.

Available for licensing is a collagen binding protein, named aegyptin, which selectively inhibits collagen-platelet aggregation, but not platelet aggregation induced by other agonists. Collagen initiates recruitment of circulating platelets and triggers platelet activation. Collagen also plays a critical role in angiogenesis. Aegyptin blocks the interaction of collagen with its major ligands, von Willebrand factor, glycoprotein VI (GPVI), and integrin alpha2beta1. These three ligands are of particular importance because von Willebrand factor plays a critical role in tethering platelets to collagen, GPVI is the major signaling platelet receptor, and integrin alpha2beta1 mediates platelet adhesion and contributes to activation. Since these ligands play a critical role in the early stages of thrombus formation, aegyptin represents a potentially highly effective therapeutic that can prevent and treat patients with thrombotic disease. Alternatively, aegyptin is potentially useful in conditions where collagen plays a critical role in angiogenesis or in conditions where excessive deposition of collagen plays a pathological role (e.g., pancreatic carcinoma).

Potential Commercial Applications: Competitive Advantages:
  • Adjuvant to “Clot busting” therapeutics.
  • Method to prevent and/or treat cardiovascular/thrombotic disease.
  • Method to treat patients undergoing invasive cardiovascular procedures (e.g., angioplasty).
  • Model to study collagen-dependent platelet aggregation or collagen-mediated angiogenesis.
  • Highly effective therapeutics can negatively modulate thrombosis in its early stages by preventing collagen interaction with three major ligands involved in thrombus/clot formation.
  • Aegyptin’s potential use as a prototype for drug delivery as an oral therapeutic, which can reduce the need for invasive surgeries that dilate blood vessels such as stents or catheters.

Development Stage:


Eric Calvo (NIAID)  ➽ more inventions...

Intellectual Property:
PCT Pat: 8,383,589 issued 2013-02-26
US Pat: 8,980,859 issued 2015-03-17
US Pat: 9,441,022 issued 2016-09-13
US Application No. 12/668,177 filed on 2010-01-07
US Application No. 13/746,631 filed on 2013-01-22
US Application No. 14/488,983 filed on 2014-09-17

Calvo E, et al. PMID 17650501
Calvo E. Collagen-platelet aggregation inhibitor from mosquito salivary glands. Biacore T100 seminar series, November 2006, St. Louis, Missouri. PMID 16907827
Yoshida S, Watanabe H. PMID 16702045
Sun D, et al.

Collaboration Opportunity:

The National Institute of Allergy and Infectious Diseases, Laboratory of Malaria and Vector Research, is seeking statements of capability or interest from parties interested in collaborative research to further develop, evaluate, or commercialize the platelet aggregation inhibitor Aegyptin. Please contact Dr. Jose Ribeiro, Head, Vector Biology Section, at 301-496-9389 or for more information.

Licensing Contact:
Peter Tung, Ph.D., M.B.A.
Phone: 240-669-5483

OTT Reference No: E-172-2007-0
Updated: Jul 31, 2012