Common cold virus delivers the goods - Gene Therapy - genetic engineering research - Brief Article

USA Today (Society for the Advancement of Education), Oct, 2002

Viruses associated with the common cold are perfect carriers for DNA, but improvements must be made in the delivery process if the virus is to be used in safe and successful gene therapy, according to Maria Croyle, assistant professor of pharmaceutics, University of Texas at Austin. Genetic engineering already permits researchers to use DNA as a sort of drug or therapy vehicle to treat disease. "But direct injection of naked DNA just doesn't work," she notes.

For some time, scientists have identified missing or altered sequences in chromosomes as contributing factors of many human illnesses, including cystic fibrosis, muscular dystrophy, diabetes, cardiovascular disease, cancer, and infectious diseases such as hepatitis and AIDS. Once scientists identify the specific gene involved in a particular disorder or illness, gene therapy emerges as a treatment option. Croyle picked the cold virus because its DNA structure is well-known, can be produced in quantity, and is manipulated easily. "And, as we know, this virus is good at infecting cells. If we can't cure the common cold virus right now, let's at least use it to our advantage."

In the last few years, the importance of safe gene delivery research has come to light after severe adverse effects were discovered during clinical trials around the country. "Enthusiasm for using viruses for gene therapy quickly diminished," Croyle explains. "And, it became apparent that development of an efficient and safe gene delivery system is one of the major challenges in the field of gene therapy. Unfortunately, our immune system will attack the virus and get rid of it before it can deliver a second dose of the therapeutic gene material. This is important in the case of the adenovirus as the gene does not stay in the body forever. It is what needs to be corrected if we are going to cure genetic disease."