Equine embryonic stem-like cells and mesenchymal stromal cells have different survival rates and migration patterns following their injection into damaged superficial digital flexor tendon
Article first published online: 20 JUL 2010
© 2010 EVJ Ltd
Equine Veterinary Journal
Volume 42, Issue 7, pages 636–642, October 2010
How to Cite
GUEST, D. J., SMITH, M. R. W. and ALLEN, W. R. (2010), Equine embryonic stem-like cells and mesenchymal stromal cells have different survival rates and migration patterns following their injection into damaged superficial digital flexor tendon. Equine Veterinary Journal, 42: 636–642. doi: 10.1111/j.2042-3306.2010.00112.x
- Issue published online: 14 SEP 2010
- Article first published online: 20 JUL 2010
- [Paper received for publication 28.10.09; Accepted 20.12.09]
- embryonic stem cells;
- mesenchymal stromal cells;
Reasons for performing study: Injury to the superficial digital flexor tendon (SDFT) is common in racing and sport horses and poor tendon regeneration leads to high reinjury rates. Autologous mesenchymal stromal cells (MSCs) are being used clinically to improve tendon regeneration but they have some practical limitations. Embryonic stem cells (ESCs) may overcome these limitations but their fate following injection into the damaged SDFT is unknown.
Objective: To inject MSCs and ESCs into distinct areas of damage in the SDFT and monitor their survival over a 3 month period.
Methods: MSCs and ESCs expressing different reporter genes were injected into separate sites of mechanically induced damage in SDFTs. Cell survival and distribution were examined post mortem after 10, 30, 60 and 90 days and host immune responses determined.
Results: Neither MSCs nor ESCs produced signs of cell-mediated immune response or tumour formation. ESC survival was high and numbers were maintained at a constant level over 90 days. ESCs were present at all sites of damage. In contrast, MSCs showed <5% survival at 10 days and numbers declined over the course of the experiment. MSCs were detected only at the site into which they were injected.
Conclusions: ESCs survived in greater numbers than MSCs in the damaged tendon and did not induce an immune response, or form tumours at the injection sites in the 90 day time period studied. ESCs also demonstrated an ability to migrate to other areas of damage within the same tendon, whereas MSCs did not.
Potential relevance: ESCs can be used allogeneically, therefore providing a possible ‘off the shelf’ source of cells for therapeutic use which overcomes the practical limitations of autologous MSCs. Furthermore, MSCs and ESCs have different survival rates and migration patterns in the damaged tendon, suggesting that they may produce different functional effects. This may have clinical relevance to treating tendon injuries in the horse.