American Society of Hirudotherapy

Immunomodulatory effects of medicinal leech saliva extract on in vitro activated macrophages

Basic science / preclinical published in Immunologic research (2024)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Research reportSalivary PharmacologyClinical TrialsGenomics & ProteomicsAyhan H et al. · Immunologic research, 2024

Abstract

Leech therapy has been utilized in modern and traditional medicine. Leech saliva contains versatile peptides and molecules that can exert anti-microbial, anti-inflammatory, anti-coagulant, and analgesic activities on the patients. The active components and molecular mechanism of action of these components should be deciphered properly in order to generate biotechnological drug candidates by recombinant production of the leech saliva peptides. In our study, we conducted LC-MS/MS and proteomics analysis on the lyophilized leech saliva extract to determine the components of it. Moreover, this extract was tested on the in vitro-activated macrophages. The extract decreased the production of the pro-inflammatory cytokines by the activated mammalian macrophages compared to the positive control groups. These results suggest that the lyophilized leech saliva can be utilized as an anti-inflammatory biotechnological drug candidate against inflammatory and autoimmune disorders. In vitro studies will be conducted to further decipher the most active ingredients in the leech saliva. These active components will be tested on the animal models of the inflammatory and autoimmune disorders to show their drug potential.

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

Publication typeJournal Article
Indexed MeSH termsAnimalsSalivaMacrophagesMiceLeechesMacrophage ActivationCytokinesHumansRAW 264.7 CellsImmunologic FactorsHirudo medicinalisProteomics

Summary

Leech therapy has been utilized in modern and traditional medicine. Leech saliva contains versatile peptides and molecules that can exert anti-microbial, anti-inflammatory, anti-coagulant, and analgesic activities on the patients.

Why This Matters for Hirudotherapy

This study used LC-MS/MS and proteomics analysis to characterize the composition of lyophilized leech saliva extract, then tested the extract on in vitro-activated macrophages, finding that it decreased production of pro-inflammatory cytokines relative to positive controls. These findings are directly relevant to hirudotherapy and the leech salivary secretome, as they provide molecular evidence for anti-inflammatory activity in leech saliva and support the identification of candidate bioactive peptides for potential recombinant drug development. The work connects to ASH's domain by beginning to decipher the active components and mechanisms underlying the known therapeutic effects of leech therapy. However, the reported effects are limited to in vitro macrophage assays, the abstract does not specify which leech species was used, and the active ingredients responsible for the observed cytokine suppression have not yet been identified or validated in vivo; the authors describe future animal-model testing as planned rather than completed.

Citation

Immunomodulatory effects of medicinal leech saliva extract on in vitro activated macrophages.

Ayhan H et al. · Immunologic research, 2024

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

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.