American Society of Hirudotherapy

Isolation and structural characterization of a potent inhibitor of coagulation factor Xa from the leech Haementeria ghilianii

Research article published in Thrombosis and haemostasis (1989)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Preclinical (animal)Drug DevelopmentCondra C et al. · Thrombosis and haemostasis, 1989

Abstract

The present work reports the discovery and characterization of an anticoagulant protein in the salivary gland of the giant bloodsucking leech, H. ghilianii, which is a specific and potent inhibitor of coagulation factor Xa. The inhibitor, purified to homogeneity, displayed subnanomolar inhibition of bovine factor Xa and had a molecular weight of approximately 15,000 as deduced by denaturing SDS-PAGE. The amino acid sequence of the first 43 residues of the H. ghilianii derived inhibitor displayed a striking homology to antistasin, the recently described subnanomolar inhibitor of factor Xa isolated from the Mexican leech, H. officinalis. Antisera prepared to antistasin cross-reacted with the H. ghilianii protein in Western Blot analysis. These data indicate that the giant Amazonian leech, H. ghilianii, and the smaller Mexican leech, H. officinalis, have similar proteins which disrupt the normal hemostatic clotting mechanisms in their mammalian host's blood.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal Article
Indexed MeSH termsAmino Acid SequenceAmino AcidsAnimalsAnticoagulantsBlotting, WesternElectrophoresis, Polyacrylamide GelFactor Xa InhibitorsLeechesMolecular Sequence DataPyroglutamyl-Peptidase ISalivary Proteins and PeptidesStructure-Activity Relationship

Summary

Isolation and structural characterization of a potent inhibitor of coagulation factor Xa from the leech Haementeria ghilianii.

Why This Matters for Hirudotherapy

This study reports the isolation and characterization of a protein from the salivary glands of the giant Amazonian leech Haementeria ghilianii that is a specific, potent (subnanomolar) inhibitor of bovine factor Xa, with an approximate molecular weight of 15,000 by SDS-PAGE. The first 43 residues show striking homology to antistasin from the Mexican leech H. officinalis, and antistasin antisera cross-reacted with the H. ghilianii protein on Western blot. For ASH's domain, this is directly relevant as molecular characterization of a leech salivary anticoagulant that disrupts host hemostasis. CAVEAT: This is a biochemical/structural characterization using bovine factor Xa with no clinical or in-vivo data; it does not involve hirudin or Hirudo medicinalis specifically.

Citation

Isolation and structural characterization of a potent inhibitor of coagulation factor Xa from the leech Haementeria ghilianii

Condra C et al. · Thrombosis and haemostasis, 1989

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