American Society of Hirudotherapy

A new cellular type in invertebrates: first evidence of telocytes in leech Hirudo medicinalis

Research article published in Scientific reports (2017)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Preclinical (animal)Genomics & ProteomicsPulze L et al. · Scientific reports, 2017

Abstract

Telocytes, a peculiar cell type, were recently found in vertebrates. Hence this cell system has been reported as ubiquitous in the bodies of mammals and interpreted as an important player in innate immunity and tissue regeneration, it is reasonable to look for it also in invertebrates, that rely their integrity solely by innate immunity. Here we describe, at morphological and functional level, invertebrate telocytes from the body of leech Hirudo medicinalis (Annelida), suggesting how these cells, forming a resident stromal 3D network, can influence or participate in different events. These findings support the concepts that leech telocytes: i) are organized in a cellular dynamic and versatile 3D network likewise the vertebrate counterpart; ii) are an evolutionarily conserved immune-neuroendocrine system; iii) form an immuno-surveillance system of resident cells responding faster than migrating immunocytes recruited in stimulated area; iv) communicate with neighbouring cells directly and indirectly, via cell-cell contacts and soluble molecules secreted by multivesicular bodies; v) present within neo-vessels, share with immunocytes the mesodermal lineage; vi) are involved in regenerative processes. In conclusion, we propose that HmTCs, integrating so different functions, might explain the innate immune memory and can be associated with several aged related diseases.

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 termsAnimalsBiomarkersHirudo medicinalisImmunity, CellularMicroscopy, Electron, TransmissionNeurosecretory SystemsWound Healing

Summary

Telocytes, a peculiar cell type, were recently found in vertebrates. Hence this cell system has been reported as ubiquitous in the bodies of mammals and interpreted as an important player in innate immunity and tissue regeneration, it is reasonable to look for it also in invertebrates, that rely their integrity solely by innate immunity.

Why This Matters for Hirudotherapy

This study describes telocytes—a cell type recently found in vertebrates—in the medicinal leech Hirudo medicinalis, characterizing them at both morphological and functional levels and proposing that these cells form a resident stromal 3D network involved in innate immunity, intercellular communication via multivesicular bodies, and tissue regeneration. This work is relevant to ASH's domain because it identifies a novel immune-neuroendocrine cell system within the medicinal leech itself, offering conceptual insight into the leech's innate immune surveillance and regenerative biology. However, the study does not involve hirudotherapy, the salivary secretome, or any clinical application, and its relevance to therapeutic leeching is indirect. The functional roles attributed to leech telocytes are proposed interpretations derived from characterization work rather than independently demonstrated therapeutic or mechanistic outcomes.

Citation

A new cellular type in invertebrates: first evidence of telocytes in leech Hirudo medicinalis.

Pulze L et al. · Scientific reports, 2017

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.