Gene transfer into canine myoblasts

We have developed and characterized cultures of healthy and dystrophic cani ne myoblasts for the evaluation of various gene transfer protocols. The num ber of desmin-positive myoblasts was elevated (>80%) in cultures of myoblas ts obtained from different muscle territories, the diaphragm muscle giving rise to the purest cultures. Myoblasts from dogs turned out to be a very co nvenient source of well transfectable and transducible cells. Transfection with plasmid DNA allowed efficient transgene expression (50% of beta-galact osidase positive cells and about 375 ng luciferase/mg protein after transfe ction with a calcium phosphate-precipitated plasmid). Infection with high c oncentrations of adenoviral and retroviral vectors allowed transgene (beta- galactosidase or mini-dystrophin) detection in about 75 to 90% of the canin e cells. Therefore, primary dog myoblast cultures represent a useful in vit ro model for viral and non-viral gene delivery, as well as for functional e valuation and cell grafting with applications in genetic diseases, vaccinat ion or production of circulating therapeutic proteins.