American Society of Hirudotherapy

Hirudins and hirudin-like factors in Hirudinidae: implications for function and phylogenetic relationships

Research article published in Parasitology research (2016)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Basic science (non-clinical)Drug DevelopmentMüller C et al. · Parasitology research, 2017

Abstract

Haematophagous leeches express a broad variety of bioactive factors that are released from the salivary gland cells into the wound of a host during feeding. Among these, hirudin is probably the best studied factor and, moreover, the only one that has successfully made the transition from nature to clinical use. Many components of the leech saliva still remain either poorly characterized or yet completely unknown. Only recently, a new class of leech-derived factors has been discovered in Hirudo medicinalis, the hirudin-like factors (HLFs). HLFs comprise typical structural features of hirudin but lack others. We were able to verify the expression of HLFs not only in two additional species of the genus Hirudo, but also in Hirudinaria manillensis. Various phylogenetic analyses based on gene and protein sequences support a sister group relationship between hirudins and HLFs. Although potential molecular targets of HLFs remain unknown, the presence of multiple isoforms in individual leeches of different genera points to key functions in the regulation of several processes associated with the blood-sucking life style of leeches.

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

Publication typeJournal Article
Indexed MeSH termsAnimalsGene Expression RegulationHirudinsLeechesPhylogenySaliva

Summary

Expression of hirudin-like factors (HLFs), first discovered in Hirudo medicinalis, was verified in two additional Hirudo species and Hirudinaria manillensis; phylogenetic analyses support a sister-group relationship between hirudins and HLFs.

Why This Matters for Hirudotherapy

This study investigated hirudins and the recently discovered hirudin-like factors (HLFs) across species of Hirudo and Hirudinaria manillensis, confirming HLF expression beyond Hirudo medicinalis and establishing a sister-group phylogenetic relationship between hirudins and HLFs. HLFs share some but not all structural features of hirudin, and their molecular targets remain unknown; however, the presence of multiple isoforms across genera suggests key roles in the blood-feeding lifestyle. The study examines the diversity and evolution of bioactive salivary molecules in haematophagous leeches and points to potentially uncharacterized components of the leech secretome. Functional characterization of HLFs remains preliminary, and the study does not establish direct therapeutic or clinical implications.

Citation

Reference (Vancouver style)

Müller C, Haase M, Lemke S, Hildebrandt JP. Hirudins and hirudin-like factors in Hirudinidae: implications for function and phylogenetic relationships. Parasitol Res. 2017;116(1):313-325. doi:10.1007/s00436-016-5294-9. PMID: 27785600

Bibliographic details (authors, volume, pages, DOI) are taken from the PubMed record.

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