A dual-marker system for quantitative studies of myoblast transplantation in the mouse

Background. Myoblast transplantation (MT) is a potential approach for gene transfer into skeletal muscle, the efficiency of which depends upon the number of copies of donor genome incorporated into the host tissue, We have developed a system for quantitative studies of MT that measures amounts of donor-derived genome in host muscles and estimates the contributions of donor cell survival and proliferation in vivo. Methods. [C-14]thymidine-labeled, male myoblasts were transplanted into female muscles, providing two donor cell markers, Y chromosome and [C-14], Th, markers were measured in muscle extracts by slot blotting and scintillation counting, respectively. Results. In each extract, the amount of Y chromosome was used to quantify donor-derived genome, whereas the radiolabel provided an estimate of cell survival, Furthermore, the different modes of inheritance of the markers meant that proliferation of surviving donor cells was detected as a change in marker ratio. Conclusions. This system provides a method for assessing potential improvements of MT.