The use of embryonic stem cells in treating horses with tendon injuries may increase their chances of a successful return to work, according to researchers.
Tendon injuries are common in horses, accounting for 30 to 50% of all musculoskeletal injuries.
Instead of regenerating healthy tendon tissue, they repair by forming scar tissue which is biomechanically inferior to healthy tendon. This predisposes horses to a high risk of re-injury. Re-injury rates of up to 67% have been reported.
Tendon injuries are therefore a leading cause of retirement in horses taking part in a wide range of disciplines.
In the early stages following a tendon injury there is a significant increase in inflammation and this is likely to contribute to the poor tissue regeneration.
Scientists at Britain’s Animal Health Trust, writing in the journal Scientific Reports, write that the use of embryonic stem cells for tendon repair appears to improve the chances of a recovery that allows them to return to active work.
Its stem-cell researchers have shown that the inflammation produced after an injury has very negative consequences for adult tendon cells.
Using a laboratory model, they found that adult tendon cells cannot produce “artificial” tendons efficiently when exposed to inflammation.
In contrast, they found that embryonic stem cells (ESCs) directed to turn into tendon cells behaved as normal when exposed to inflammation.
“We were able to demonstrate that these tendon cells express different levels of receptors for inflammatory proteins on their surface,” said Dr Debbie Guest, the trust’s head of stem cell research.
“This means that these stem cells may provide a useful source of cells for clinical transplantation into the injured tendon as they are unlikely to suffer any negative effects from being placed into an inflamed environment.”
The trust’s research team says this opens the possibility of further studies to understand more about how ESC-derived tendon cells protect themselves from inflammation. This could lead to new drug treatments that could be used to protect adult tendon cells after an injury.
Protecting tendon cells from inflammation could help to improve the regeneration of healthy tendon tissue to reduce the risk of re-injury and allow more horses to remain in active work.
Funding for a follow-up study by the trust, in collaboration with the Royal Veterinary College, has been secured from Britain’s Horserace Betting Levy Board. The team is hopeful that new treatment options for this old problem may soon be developed.
The recent research was funded by the Horserace Betting Levy Board, the Racing Foundation, the Alice Noakes Memorial Charitable Trust, and Beryl Evetts and Robert Luff Animal Welfare Trust.
A novel mechanism for the protection of embryonic stem cell derived tenocytes from inflammatory cytokine interleukin 1 beta
Alyce McClellan, Richard Evans, Cheryl Sze, Shohei Kan, Yasmin Paterson and Deborah Guest.
Scientific Reports volume 9, Article number: 2755 (2019) https://doi.org/10.1038/s41598-019-39370-4