American Society of Hirudotherapy

Cross-Species LDTI Variants

Comparative LDTI gene family analysis across 4 medicinal leech species (H. nipponia, H. manillensis, W. pigra, H. tianjinensis) — Xiao 2025 documents H. nipponia as optimal therapeutic candidate.

Preclinical / mechanisticLast updated: 2026-05-27 · Reviewed by ASH Editorial Board
Molecular weight of Cross-Species LDTI Variants compared with other characterized leech-derived compoundsHementerin80 kDaHementin80 kDaHementin-Like Protein (HLP-1)80 kDaLeech Collagenase70 kDaHaemadipsa yanyuanensis Progr…70 kDaLeech Apyrase67 kDaCalin65 kDaHyaluronidase60 kDaAntithrombin III binding prot…58 kDaCollagenolytic Fibrinolysin55 kDaLeech Thrombospondin-Like Pro…50 kDaCross-Species LDTI Variants5.5 kDa
Molecular weight (kilodaltons) of Cross-Species LDTI Variants (highlighted) alongside other characterized leech salivary compounds. Smaller proteins/peptides generally diffuse and act faster.

Mechanistic Evidence Box

Preclinical / mechanistic
Page type
Compound profile
Evidence type
Comparative LDTI gene family analysis across 4 medicinal leech species (H. nipponia, H. manillensis, W. pigra, H. tianjinensis) — Xiao 2025 documents H. nipponia as optimal therapeutic candidate.
Evidence level
In vitro
Drug vs leech
Recombinant (genetically expressed)

Clinical translation limit

Cross-species LDTI in vitro anticoagulation activity (via P. pastoris recombinant expression and chromogenic substrate assays) does NOT establish clinical efficacy. No FDA-approved derivative exists; none of the four species is the FDA-cleared K040187 medicinal leech.

Molecular Profile

Category
Proteinase Inhibitor
Evidence tier
Preclinical
Molecular weight
5,500 Da
Source species
Hirudo nipponia, Hirudinaria manillensis, Whitmania pigra, Hirudo tianjinensis
Discovered
2025 · Xiao M et al.
Cross-Species LDTI Variants molecular structure

Biological Targets

  • tryptase / mast-cell-derived serine proteases (variable potency by species)

Key Citations

  1. Xiao M et al. (2025), Biology (Basel) · PMID 41007389

External Resources

    Related Proteinase Inhibitor Compounds

    This website provides educational information and does not constitute medical advice, diagnosis, or treatment recommendations. Medicinal leech therapy carries clinically meaningful risks and should be performed only by qualified clinicians under institutionally approved protocols. FDA 510(k) clearance for medicinal leeches is limited to specific indications; investigational and off-label discussions are labeled accordingly. For patient-specific guidance, consult a qualified healthcare provider.