Cell-based Therapies for Equine Joint Disease

The Current ‘State of Play’ of Regenerative Medicine in Horses: What the Horse Can Tell the Human

“…No synergy was observed when stem cells and PRP were combined in an experimental study on tendon injuries in sheep [97], an observation consistent with the hypothesis that while MSCs are immunosuppressive PRP is proinflammatory thereby negating the positive effects of stem cell implantation. An alternative approach utilized a direct injection of MSCs into the joint space, which reportedly carries long-term advantages, with repair tissue remaining firm following a year of strenuous exercise [98]. However, MSCs do not appear to be effective at stimulating repair in all types of osteoarthritis and so further study is necessary before drawing definitive conclusions on efficacy [99].…”

Optimization of a nonviral transfection system to evaluate Cox-2 controlled interleukin-4 expression for osteoarthritis gene therapyin vitro

“…Because of their small size, however, the results obtained from such distant models may not always be valid in terms of their applicability to humans . Consequently, OA research tends to replace the rodent models with large animal models, such as dogs or horses, which both show all features of the naturally occurring human disease . Horses, in particular, offer many advantages because they are much more similar to humans with respect to the anatomical features of their joints, such as size, cartilage diameter and pathways of chronic inflammation .…”

Mesenchymal stem cell therapy in horses: useful beyond orthopedic injuries?

“…Due to the hypocellular and avascular nature of articular cartilage, the ability to obtain effective repair is limited (Frisbie & Stewart 2011). Full-thickness cartilage defects in horses heal with fibrous tissue that might become fibrocartilage, which has inferior biomechanical properties compared to articular hyaline cartilage (Taylor et al 2007).…”

“…Full-thickness cartilage defects in horses heal with fibrous tissue that might become fibrocartilage, which has inferior biomechanical properties compared to articular hyaline cartilage (Taylor et al 2007). Giving the ability of MSC to undergo chondrogenic differentiation, much of the recent research on cartilage resurfacing in the horse has focused on the use of these stem cells (Figure 1) (Frisbie & Stewart 2011). Although MSC differentiation into cartilage has been demonstrated in vitro, a successful in vivo use of such cell-based therapies might be hampered by the compressive load exerted on the injected cells and scaffolds (Koch et al 2009).…”

“…Even more challenging is the treatment of osteoarthritis since the articular cartilage damage is often more diffuse and not only the corresponding surfaces, but also the periarticular tissues such as the synovial membrane, the joint capsule, ligaments, menisci, and subchondral bone, can be impaired (Frisbie & Stewart 2011). Nevertheless, a beneficial effect of MSC on cartilage morphology and histology has been demonstrated in various osteoarthritis animal models (Murphy et al 2003;Agung et al 2006;Alfaqeh et al 2008;Grigolo et al 2009;Matsumoto et al 2009).…”