American Society of Hirudotherapy

Genetic Variation and Gene Expression of the Antimicrobial Peptide Macins in Asian Buffalo Leech (Hirudinaria manillensis)

Yu Y, Tang L, Xiao M, Yin J, Ye T, Sun R, Ai R, Zhao F, Huang Z, Lin G (2025) · Biology · n=30

RCT evidence detailTrial reference
GRADE Very LowInsufficient evidence
Sample size of this trial compared with other venous-congestion-flap trialsMarquard JM 20251215Bishop JL 2023843Doğan S 2024570Troeltzsch M 2016330Kucur C 2015260Wang ZD 2022210Lehnhardt M 202196Kruer RM 201459Mozafari N 201056Yu Y 202530
This trial (highlighted) by sample size alongside other indexed venous-congestion-flap trials. Larger trials generally carry more statistical weight.

Study Profile

Design
genome and transcriptome sequencing of 30 Asian buffalo leech (Hirudinaria manillensis) individuals; integrative analysis with three other leech species (Hirudo medicinalis, Hirudo nipponia, Whitmania pigra); Chinese consortium led by Jinggangshan University
Sample size (n)
30
Intervention
Comparative characterization of three macin antimicrobial peptide genes (Hman1, Hman2, Hman3) across 30 H. manillensis individuals, with cross-species comparison
Comparator
Macin expression and sequence variation in H. medicinalis, H. nipponia, and W. pigra
Primary endpoint
Sequence conservation and transcripts-per-million (TPM) expression of macin genes
Primary result
Hman1 conserved (translatable in all individuals); Hman2 and Hman3 highly variable with frequent pseudogenization (4 Hman2, 28 Hman3 pseudogenes); total macin expression in H. manillensis <1/20 of comparator species; Hman1 retains function while Hman2/Hman3 appear to be losing antibacterial roles
Follow-up duration
Not applicable — comparative genomics

Key Findings

  • 30 H. manillensis individuals sequenced - largest population genomics study to date for this species
  • Three macin genes identified: Hman1 (conserved), Hman2 (variable), Hman3 (variable + pseudogenized)
  • Macin expression in H. manillensis <1/20 of comparator leech species
  • Pseudogenization evidence suggests Hman2/Hman3 losing antibacterial function
  • Provides foundation for leech-derived antimicrobial peptide drug discovery against MDR pathogens

Limitations

  • Population sampling limited to Chinese H. manillensis populations
  • No functional anti-Aeromonas, anti-Vibrio, or anti-MRSA antimicrobial assays
  • Sequence-based pseudogenization claims unvalidated by expression-level functional studies
  • No mammalian or therapeutic application demonstrated
  • Hirudinaria manillensis is not the K040187-cleared device leech in the US

Clinical Implications

Yu 2025 expands the leech-derived antimicrobial-peptide literature in the context of growing global concern about antibiotic resistance. While not directly applicable to US K040187 clinical practice, the data inform broader translational research on leech-pharmacology-derived antimicrobials — a research direction with potential downstream relevance to hirudotherapy-associated infection prevention (per Brauer 2024 MAUDE resistance data).

Related Trials

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.