In vitro model of equine muscle regeneration

Equine satellite cells are responsible for muscle healing and regeneration in the mature horse. We describe the in vitro cell culture conditions requi red for clonal populations of equine satellite cells to undergo both prolif eration and differentiation. Our hypothesis is that these in vitro conditio ns model regeneration of muscle and can be used to evaluate potential thera peutics. In this study, 2 areas of satellite cell response were tested: pro liferation of clones induced by growth factors, and fusion induced by cultu re conditions. Equine satellite cell clones showed differences in their res ponse to growth factors as well as accumulation of cellular protein concent rations. Equine satellite cells proliferate in response to both human and b ovine FGF. IGF-1, a powerful mitogen of other satellite cell culture system s, was not as effective for inducing equine satellite cell proliferation. P rotein concentrations were also measured in satellite cell cultures. Clones differed in cellular protein produced depending on growth conditions. Cond itions inducing differentiation into myotubes was also determined for a 96 well assay and can be used to study the final stage of functioning muscle p roduction. This in vitro model is the first step in identifying potential t herapeutics to speed wound healing and promote muscle regeneration in horse s.