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Defensins

low risk

Also: Alpha-defensins · Beta-defensins · Innate immunity peptides

Moderate Evidence Research Only

Reference entry for defensins — a family of cysteine-rich antimicrobial peptides central to innate immunity. Found in neutrophils (alpha-defensins) and epithelial cells (beta-defensins). Broad-spectrum antimicrobial activity against bacteria, fungi, and viruses. Drug development interest for antibiotic-resistant infections.

Molecular Weight
3–5 kDa
Formula
Various (6-10 cysteine-stabilized peptides)
Common Dosing
Not standardized for systemic use; topical formulations in trials
Category
research
Last Reviewed
2025-01-15

Reported Benefits

Broad-spectrum antimicrobial

Moderate Evidence 89 studies

Well-characterized innate immunity function. Active against MRSA, Candida, HSV in vitro and in vivo.

Mechanism of Action

Cationic peptides disrupting microbial membranes via electrostatic interaction; also modulate adaptive immunity via chemotactic and dendritic cell activation functions.

Antibiotic Resistance Context

With conventional antibiotic resistance escalating, defensins and other antimicrobial peptides (AMPs) are intensively studied as alternative or adjunctive antimicrobials. Their membrane-disruption mechanism makes resistance development substantially harder than with antibiotics targeting specific metabolic pathways.

Regulatory Status

Research Only

Safety Profile

Side Effects

  • •Inflammatory activation at high concentrations

Contraindications

  • •Autoimmune conditions (theoretical)

Primary Uses

Innate immunityAntimicrobialAntiviralWound healing

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Disclaimer: This information is for educational and research purposes only. Not medical advice. Consult a qualified healthcare provider before using any compound.