Cell therapy for tendinitis, experimental and clinical report

Area of Science:

• Veterinary Medicine
• Regenerative Medicine
• Equine Sports Medicine

Background:

• Tendonitis in horses significantly impacts athletic performance and career longevity.
• Current treatments for equine tendon injuries have variable success rates.
• Cell-based therapies offer a promising avenue for tendon tissue regeneration.

Purpose of the Study:

• To compare the efficacy of cultured bone marrow mesenchymal cells (cBMSC) and bone marrow mononucleated cells (BMMNCs) in repairing collagenase-induced equine tendonitis.
• To evaluate the regenerative potential of BMMNCs in naturally occurring flexor tendon and suspensory ligament lesions in horses.
• To assess the return-to-racing rates and re-injury rates following BMMNC transplantation.

Main Methods:

• An equine model of collagenase-induced tendonitis was established in 6 horses.
• Intralesional injections of cBMSCs, BMMNCs, or placebo were administered.
• Ultrasound, histology, and immunohistochemistry were used for evaluation.
• A subsequent study involved 20 horses with spontaneous tendon lesions treated with autologous BMMNCs, followed by a controlled exercise program.

Main Results:

• Both cBMSC and BMMNC transplantation demonstrated effectiveness in regenerating tendon tissue.
• Qualitatively similar regeneration of tendon extracellular matrix (type I/III collagen ratio, fiber orientation, COMP expression) was observed with both cell types.
• In horses with spontaneous lesions treated with BMMNCs, ultrasound characteristics improved, lameness resolved, and 60% returned to racing with a 25% re-injury rate.

Conclusions:

• Cultured bone marrow mesenchymal cells and bone marrow mononucleated cells are effective in regenerating tendon tissue in horses.
• BMMNC transplantation shows promise for treating spontaneous tendon and suspensory ligament injuries, facilitating return to athletic function.
• Cell-based therapy with BMMNCs represents a viable option for equine tendon repair, with a notable percentage of treated horses returning to racing.