Direct gene transfer into muscle.

Gene therapy has great promise for the treatment and the prevention of a broad range of inherited and acquired diseases. Gene transfer methods currently explored include the use of viral vectors and physical-chemical methods. Plasmid DNA can be taken up by skeletal muscle cells in vivo without any special delivery mechanism and persist long-term in an extrachromosomal, non-replicative circular form. Thus, foreign genes can be expressed permanently in skeletal muscle. At present the efficiency of gene transfer is not high enough to treat genetic muscle diseases. However, even at the relatively low efficiency of expression we are able to achieve at present, plasmid DNA transfer seems to be a very promising way of programming cells in vivo to secrete proteins for immunization purposes.