Current status of the anticoagulant hirudin: its biotechnological production and clinical practice

Abstract

Hirudin is a potent thrombin inhibitor originally derived from the medicinal leech, Hirudo medicinalis. Owing to its high affinity and specificity for thrombin, hirudin has been intensively investigated for research and therapeutic purposes. The investigation of hirudin has contributed greatly to the understanding of the mode of action of thrombin and the clotting system. Hirudin and several hirudin analogues have also been demonstrated to have several advantages as a highly specific anticoagulant over the most widely used drug, heparin. Due to the great demand for hirudin in physicochemical and clinical studies, various recombinant systems have been developed, using bacteria, yeasts, and higher eukaryotes, to obtain the biologically active hirudin in significant quantities. After 10 years of clinical applications, two recombinant hirudins and a hirudin analogue have gained marketing approval from the United States Food and Drug Administration, for several applications. Clinical trials are currently ongoing for other treatments for thrombotic disease. As a consequence, it is conceivable that hirudin may expand its therapeutic utility over heparin in the near future.

Extracellular secretion of anticoagulant peptide hirudin in Lactococcus lactis using SP310mut2 signal peptide

“…In addition, hirudin is a typically secreted polypeptide which requires three intramolecular disulfide bonds (to acquire its native conformation and biological activity. Hirudin possesses valuable therapeutical potential as anticoagulant and antithrombotic agent because it is the most potent thrombin-specific inhibitor so far known and does not inhibit other enzymes in the blood coagulation or fibrinolytic pathways (Sohn et al 2001). Interestingly, hirudin can be taken orally (Yan et al 2004;Cen et al 2006).…”

“…There are three principal hirudin variants composed of 65-66 amino acids and designated as HV1, HV2, HV3, respectively (Sohn et al 2001). In addition, hirudin is a typically secreted polypeptide which requires three intramolecular disulfide bonds (to acquire its native conformation and biological activity.…”

Genetic differentiation between two species of the medicinal leech, Hirudo medicinalis and the neglected H. verbana, based on random-amplified polymorphic DNA

“…There has been a recent renaissance in the medical use of leeches, both as a source of pharmaceutical substances and directly, for example in plastic surgery or dermatology (e.g. Sohn et al 2001;Whitaker et al 2004). Also, the medicinal leech is widely used in neurophysiological and developmental genetic studies and for educational purposes.…”

1H NMR assignment and secondary structure of recombinant RGD‐hirudin

“…10 To date, still few recombinant hirudins and hirudin analogues have been marketed as anticoagulants for patients with different thrombotic diseases. 5 In our laboratory, in order to develop recombinant hirudin as a therapeutic reagent, a new type of recombinant RGD-hirudin has been successfully cloned, expressed in the methylotrophic yeast Pichia pastoris and purified. 11 By active assay, it has been proved that the recombinant RGD-hirudin not only has a specific activity of 12 000 ATU mg 1 , but also shows the dual function of anti-thrombin and anti-platelet aggregation, whereas wild-type hirudin has the single anti-thrombin function.…”

“…5 Since hirudin is one of the most potent and specific thrombin inhibitors, clinical applications for recombinant hirudins and hirudin analogues have been intensively investigated. 6,7 However, until now, pure hirudin crystals have not been obtained, so the structures were mainly studied by multi-dimensional NMR in solution 2 -4,8,9 or by x-ray crystallography in the form of a thrombin-hirudin complex.…”