American Society of Hirudotherapy

The salivary transcriptome of Limnatis nilotica and orthology determination of major leech anticoagulants

Transcriptomics study published in Parasitology (2019)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Preclinical (animal)Genomics & ProteomicsSalivary PharmacologySafety & Infection ControlIwama R et al. · Parasitology, 2019

Abstract

Bloodfeeding requires several adaptations that allow the parasite to feed efficiently. Leeches and other hematophagous animals have developed different mechanisms to inhibit hemostasis, one of the main barriers imposed by their hosts. Limnobdella mexicana is a member of the leech family Praobdellidae, a family of host generalists known for their preference to attach on mucosal membranes of mammals, such as those in nasopharyngeal cavities, bladders and ocular orbits. Previous studies have hypothesized a positive relationship between diversity of anticoagulants and diversity of hosts in bloodfeeding leeches. However, orthology determination of putative anticoagulants and the lack of standardization of sequencing effort and method hinder comparisons between publicly available transcriptomes generated in different laboratories. In the present study, we examine the first transcriptome of a praobdellid leech and identify 15 putative anticoagulants using a phylogeny-based inference approach, amino-acid conservation, Pfam domains and BLAST searches. Our phylogenetic analyses suggest that the ancestral leech was able to inhibit factor Xa and that some hirudins that have been reported in previous studies on leech anticoagulants may not be orthologous with the archetypal hirudin.

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

Publication typeJournal ArticleResearch Support, Non-U.S. Gov't
Indexed MeSH termsAnimalsComputational BiologyFactor Xa InhibitorsGenetic VariationLeechesPhylogenySalivary Proteins and PeptidesTranscriptome

Summary

Salivary transcriptome of nasal-leech parasite Limnatis nilotica and orthology mapping of major leech anticoagulants across species — important for understanding leech-clade salivary biology.

Why This Matters for Hirudotherapy

This study examined the first transcriptome of a praobdellid leech, identifying 15 putative anticoagulants through phylogeny-based inference, amino-acid conservation, Pfam domains, and BLAST searches. Phylogenetic analyses suggested that the ancestral leech was able to inhibit factor Xa and that some hirudins reported in previous studies may not be orthologous with the archetypal hirudin. For ASH, this work is relevant because it investigates the diversity of putative anticoagulants in leeches and questions the orthology of previously reported hirudins, topics central to understanding leech-derived bioactive molecules. The key caveat is that this is a transcriptomic study without functional validation of the identified putative anticoagulants, and the abstract does not address any therapeutic or hirudotherapy applications.

Citation

The salivary transcriptome of Limnatis nilotica and orthology determination of major leech anticoagulants.

Iwama R et al. · Parasitology, 2019

Added to ASH library: May 27, 2026 · Site last updated: June 18, 2026

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