Skeletal muscle as an artificial endocrine tissue.
Muscle has the ability to take up and express engineered genes and, because it is a post-mitotic tissue, their half-life of expression is prolonged. Although muscle is not regarded as a secretory tissue, in many cases, the gene products enter the systemic circulation. The possibility exists, therefore, of using this approach to alter levels of endocrine and paracrine factors. As a therapeutic procedure, this method has an advantage over the administration of the peptide/protein, which has a relatively short half-life and requires repeated injections. Engineered genes in plasmid or viral vectors under the control of a muscle-specific regulatory sequence may be introduced by intramuscular injection or by the introduction of transfected myoblasts. The latter is also being used in bioreactors to produce medicinal proteins/peptides in vitro as these offer some advantages over bacterial expression systems. However, for gene therapy purposes, there are still safety issues to be addressed.
Goldspink
Geoffrey
G
Basic Medical Sciences and Department of Surgery, Royal Free and University College Medical School, Royal Free Campus, University of London, London, UK. goldspink@rfc.ucl.ac.uk
D017690:Cell Transplantation; D004702:Endocrine Glands / Q000502:physiology*; D004921:Erythropoietin / Q000172:deficiency; D005786:Gene Expression Regulation / Q000502:physiology; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000009:adverse effects; D019382:Human Growth Hormone / Q000172:deficiency; D006801:Humans; D018482:Muscle, Skeletal / Q000502:physiology*
D004921:Erythropoietin; D019382:Human Growth Hormone