Ultrastructural and morphological characterization of Trypanosoma bubalisi reveals an active endocytic system
Research article published in Acta tropica (2025)
Abstract
Trypanosoma bubalisi is a newly identified mammalian trypanosome isolated from a freshwater leech (Hirudinaria manillensis) and the water buffalo (Bubalus bubalis) is considered its host. Despite the detailed morphological description of in vitro cultivated forms of this trypanosome, little is known about its ultrastructure. In this study, a detailed ultrastructure of T. bubalisi was characterized using scanning electron microscopy, transmission electron microscopy and focused ion beam-scanning electron microscopy. Two membrane-bound organelles were identified, multivesicular body-like vesicles (ve1) and large lipid-rich vesicles resembling reservosomes (ve2), alongside an extracellular 'beads-on-a-string' structure. These all appear to be associated with endocytosis or secretion. Three-dimensional reconstructions confirmed the organization and distribution of the two membrane-bound organelles. Functional assays using Tomato lectin and Lyso-Tracker demonstrated that ve2 is involved in endocytic uptake and may act as a terminal storage compartment. Compared to the pathogen causing Nagana, Trypanosoma brucei, T. bubalisi showed higher endocytic activity under both 27 °C and 4 °C conditions. These findings suggest that T. bubalisi possesses an active endocytic system and may share conserved mechanisms of material transport and storage with the pathogen causing Chagas' disease, Tryponosoma cruzi.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Peer-reviewed clinical and outcomes research relevant to medicinal leech therapy and its biology. Indexed in PubMed and verified against the NCBI record.
Why This Matters for Hirudotherapy
This study characterized the fine structure of Trypanosoma bubalisi, a newly identified mammalian trypanosome, using electron microscopy and functional dye assays; it identified two membrane-bound organelles and reported higher endocytic activity than the Nagana pathogen T. brucei. Honest framing for ASH: this is a parasitology and cell-biology paper, and the medicinal leech (Hirudinaria manillensis) appears only as the source organism the trypanosome was isolated from, not as a therapeutic agent. The work tells us nothing about hirudotherapy, the leech salivary secretome, or any anticoagulant or clinical effect, and its relevance to leech therapy is essentially a naming/host-biology overlap rather than a substantive connection. As a preclinical ultrastructural study of a protozoan parasite, it should not be read as evidence for or about medicinal-leech treatment.
Citation
Ultrastructural and morphological characterization of Trypanosoma bubalisi reveals an active endocytic system.
Wang et al. · Acta tropica, 2025
Added to ASH library: May 28, 2026 · Site last updated: June 18, 2026