The current status of myoblast transfer.

As a means of correcting the defect in the muscles of Duchenne muscular dystrophy (DMD) patients, myoblast transplantation has the advantage of utilizing normal biological mechanisms of repair of this tissue. Thus, it has the potential not only for correcting or complementing the genetic defect, but also for restoring the structure and function of pathologically damaged muscle tissue. However, it is also subject to many of the problems of other genetic therapies for muscle tissue, especially the problem of dispersing the therapeutic agent throughout the muscle mass and that of immune rejection of the genetically corrected tissue. In this article, these problems are discussed. In addition the history of cell transplantation therapy for DMD is presented as an example of the practical difficulties that arise from over eager application to human trials of preliminary data from animal experiments. Recent demonstrations that stem or early precursor cells from a muscle and from the bone marrow are able to disperse to sites of muscle damage via the blood vascular system and to participate in muscle repair raise the hope that this mode of therapy may be applicable to muscular dystrophies.