Bioartificial Muscles in Gene Therapy

Most recent gene therapy protocols describe in vivo delivery of foreign genes by means of injecting adenoviral, adeno-associated, or lentiviral particles (1 –4 ). Although these delivery systems show great promise, it is reasonable to believe that ex vivo gene therapy may move through clinical trials more swiftly due to the added safety factors associated with keeping all virus outside the patient. Ex vivo gene transfer into rapidly dividing cells by means of retroviral transduction or stable transfection has produced cells secreting a vast variety of growth factors, including insulin (5 ), granulocyte colony-stimulating factor (6 ), growth hormone (7 ,8 ), dopamine (9 ), and erythropoietin (10 ). These cells can then be transplanted back into the body to provide a therapeutic protein treatment.