Paving the Way: Defining Safety, Consistency & Clinical Readiness in Equine Biologics

BACKGROUND

The problem this study addresses

Musculoskeletal (MSK) injuries are prevalent in equine and human athletes. Biologic tissue allografts, particularly from the umbilical cord (UC), offer potential for MSK tissue repair. However, characterization and in vivo biocompatibility data to date are limited.

OBJECTIVES

What the study set out to do

To characterize the protein content of a cryopreserved microparticulate equine UC allograft and evaluate its biocompatibility and safety when injected into joints, tendons, and ligaments in horses.

METHODS

How the work was done

Proteomic analysis using mass spectrometry and ELISA was performed on UC allograft samples. Three in vivo studies were conducted:

1. A randomized controlled trial in eight clinically normal horses to assess the immune response and safety of the product.
2. A case study in three horses with MSK disease to evaluate clinical impact.
3. A controlled pathologic study for acute tissue biocompatibility where clinical, hematologic, synovial fluid, and histologic parameters were evaluated.

RESULTS

What the work showed

Proteomics identified +2,600 proteins, with 80 highly abundant and 224 with moderate abundance. Key proteins included structural collagens, anti-inflammatory mediators (e.g., IL-1ra), and regenerative factors (e.g., VEGF). In vivo, UC injections caused transient synovitis resolving by Day 5, with significant increases in IL-1ra, IL-10, and VEGF.

No systemic inflammation or adverse events were observed. Histology showed no immune response or foreign material in lymph nodes. Mean lameness score, ligament pressure score and mean carpal flexion score all showed an improvement in 28-day time frame for the three horses treated.

CONCLUSIONS

What it means for clinical use

The equine UC allograft is protein-rich, batch consistent, and biocompatible. It is safe for intra-articular and intralesional use, supporting its potential as a biologic scaffold for MSK tissue repair and future clinical applications.

Study Snapshot

Aspect	Details
Title	Cryopreserved Equine Umbilical Cord Tissue Allograft Characterization and Biocompatibility in Vivo in Musculoskeletal Tissues
Authors	Alicia L. Bertone, Craig Reinemeyer, George Tsaprailis, Daniel Ragland, Britta Leise
Published In	BMC Medicine, 2025
DOI	10.1186/s12916-025-04231-7
Objective	To characterize the protein content and assess the in vivo biocompatibility of a cryopreserved, microparticulate equine umbilical cord (UC) allograft for musculoskeletal (MSK) tissue supplementation.
Key Findings	UC allograft contains consistent proteins across all batches. 2,600+ proteins were identified across donors. Lot-to-lot consistency in protein expressed and identified was noted. Low inflammatory cytokine levels; high anti-inflammatory markers (e.g., IL-1ra, IL-10) were observed. No adverse events in normal or diseased horses. Improved pain and lameness scores in horses with OA, desmitis, and tendonitis.
Applications	Injectable biologic scaffold for joints, tendons, and ligaments. Potential preclinical model for human UC therapies.
Innovation	First controlled, randomized in vivo study of equine UC allograft showing safety, consistency, and therapeutic potential.
Web Link	link.springer.com/article/10.1186/s12916-025-04231-7