Stem cell therapy is a promising application in the emerging field of veterinary regenerative medicine and surgery.
Stem cells can differentiate into different cell types, multiply massively, spontaneously migrate to damaged tissues, produce important factors for tissue repair and they even posses immunomodulating properties. In short the theoretical possibilities for therapy will ultimately be unlimited and very accessible when allogenic stem cells are used.
- Joint pathalogies
- Tendon lesions
- Metabolic diseases
In horses, the use of cell-based therapies to treat orthopedic injuries, such as tendon lesions (Spaas et al., 2012a) is a hot topic. In this regard, in 2001 one of the first reports on the use of cellular bone marrow to aid tendon repair was described (Herthel, 2001). In this study, 84% (n=100) of the horses with a naturally-occurring suspensory ligament desmitis returned to full work after bone marrow treatment, in contrast to the control group, where only 15.2% (n=66) of the horses reached the same performance level as before. Since the goal of stem cell (SC) therapy is to reach ‘restitutio ad integrum’ (restitution of the original, functional state), these findings are very promising and, all the more so, because they are supported by several in vivo studies. In another study, the beneficial effects of mesenchymal stem cells (MSCs) were evaluated in horses suffering from superficial digital flexor tendinosis and they found that 82% (n=168) of the horses treated with MSCs performed at their original level without re-injury in the next year (Smith, 2008), whereas 42-44% of the horses with superficial digital flexor tendinosis treated with conservative and reparative therapy with hyaluronic acid and polysulfated glycosaminoglycans re-injured (Dyson, 2004).
In horses, the use of blood-derived stem cells has been recently described. The use of these cells has been reported for the treatment of chronic suspensory ligament desmitis (Spaas et al., 2011). Moreover, the use of allogenic tenogenic induced MSCs in combination with platelet-rich plasma (PRP) to treat superficial digital flexor tendon and suspensory ligament lesions has been reported in 25 horses (Broeckx et al., 2012; Spaas, 2012). Furthermore, the treatment of distal check ligament desmitis with tenogenic induced MSCs has been compared to PRP treatment with favorable results for the stem cell therapy (Beerts et al., 2013). In addition, the administration of blood-derived MSCs has been proposed as a promising treatment for other diseases such as arthrosis (Spaas et al., 2012b).
It has to be mentioned though, that stem cells are very sensitive and the success of this therapy depends on the way the cells are manipulated and injected, as previously reported by our group (Broeckx et al., 2013).