Pilot study characterizing a single pooled preparation of equine platelet lysate for nebulization in the horse.
Authors: Egli Patricia, Boone Lindsey, Huber Laura, Higgins Courtney, Gaonkar Pankaj P, Arrington Justine, Naskou Maria C, Peroni John, Gordon Julie, Lascola Kara M
Journal: Frontiers in veterinary science
Summary
# Editorial Summary: Equine Platelet Lysate for Nebulization Platelet lysate (PL) possesses established antimicrobial and anti-inflammatory properties that could benefit horses with bacterial pneumonia, yet whether nebulization—a non-invasive delivery method—preserves these therapeutic effects remains unclear. Researchers nebulized a pooled equine PL preparation using an equine-specific nebulizer (Flexivent®), then compared protein composition (growth factors, antimicrobial peptides, cytokines) and antimicrobial activity against three common equine respiratory pathogens before and after treatment. Nebulization proved technically feasible, delivering particles at a median size of 4.99 µm with 52% of particles ≤5 µm—ideal for respiratory deposition—at a flow rate of 0.8 ml/min; however, the process altered PL's protein composition, with mixed effects on bacterial growth inhibition depending on the pathogen. Whilst PL reduced carrying capacity for *Streptococcus equi* subsp *zooepidemicus* regardless of nebulization, *Rhodococcus equi* (both wild-type and multidrug-resistant strains) showed paradoxical increases in growth parameters post-nebulization, suggesting nebulization may compromise efficacy against this pathogen. This pilot work establishes feasibility for further investigation but highlights the need for careful characterization of how the nebulization process affects PL's therapeutic properties before clinical application in respiratory disease management.
Read the full abstract on PubMed
Practical Takeaways
- •Nebulization of platelet lysate appears technically feasible for delivery to equine lungs based on particle size characteristics, but clinical efficacy remains unproven
- •Results against R. equi are concerning—platelet lysate may not inhibit and could potentially support growth of this pneumonia pathogen in horses; do not use for suspected R. equi pneumonia until further research clarifies this finding
- •This is early-stage research; wait for in vivo studies before considering platelet lysate nebulization as a treatment option for equine respiratory disease in your practice
Key Findings
- •Equine platelet lysate nebulization produced particle sizes of 4.991 μm with 52% of particles ≤5 μm, suitable for lower respiratory tract deposition
- •Nebulization altered protein composition of platelet lysate but did not change antimicrobial effect against E. coli and S. zooepidemicus
- •Platelet lysate reduced carrying capacity for S. zooepidemicus but paradoxically increased growth parameters for R. equi (both WT and MDR strains) post-nebulization
- •Technical feasibility of nebulizing equine platelet lysate was demonstrated, but further investigation is needed before clinical application