Cyclosporin A as a means of preventing rejection of skeletal muscle allografts in mice.

Isografts and allografts of skeletal muscle inserted into the limbs of mice initially degenerate. After some 5 to 8 days newly formed myotubes appear in the graft which develop into mature muscle fibers. In nontolerant hosts allografts are rejected between the 10th and 12th days. In mice treated with cyclosporin A, this effect persists for some 12 days after the end of treatment. Isoenzyme marker studies indicate that the regenerated graft is composed of both host and donor tissue. Donor isoenzyme does not persist when grafts are rejected.