Fluorescent gene therapy

Within a few years, a couple of "jabs", a saline solution full of genes and a few electric impulses may be a cure for cancer, HIV and diabetes. A green mouse is the scientists' first step on the road to success.

By Christina B. Winge

This new method of treatment is simple but efficient. Physiological saline, to which genes have been added, is injected into the muscle, while a little machine transmits electric impulses to the tissue via two needle electrodes. The electric impulses destabilize the cell membrane, allowing the genes to pass more easily into the cell. As the genes make themselves at home in the cell nucleus they tell the muscle to start manufacturing the proteins needed. By using different genes different proteins can be produced to combat specific diseases. Scientists hope that in a few years this form of localised medical treatment will be able to cure us of several life-threatening illnesses.
The "greening" of the muscular tissue enables the scientists to see the effects of the genetic transfer process with the naked eye. The fluorescence is obtained from the genes of a luminous jellyfish, but has no therapeutic effect in itself.

Current augments the effect
Scientists have been injecting genes into muscular tissue for ten years. However, injecting genes on their own is of limited value as a form of medical treatment - the technique works only on small animals, because the quantity of genes that are taken up by the muscle is not great enough to have any effect on larger animals or human beings. Professor Terje Lømo and biology researcher Iacob Mathiesen of the University of Oslo attempted to overload muscular tissue in the hope of creating breaks in the structure of the muscle. The results were all that the scientists could desire, though not because of muscular overexertion. Closer study revealed that the cell membrane was riddled with microscopic holes. These tiny openings enabled the genes to be taken up by the muscular tissue to a greater extent than before.

New treatment equipment
The good results led to the involvement of SINTEF technologists in the project. Their task was to develop an apparatus that would be capable of controlling the electric current at micro level.
"The level of accuracy was important because the medical scientists needed to maintain full control over every individual pulse and frequency. At the same time, all the data had to be digitally logged," says Olav Storstrøm, a research scientist at SINTEF.
Now the instrument has been built and the method of treatment patented. The machine sends electric impulses directly into the muscle via two needle electrodes; these also communicate with the computer, which both logs the treatment process and enables the doctors to alter the current characteristics as they require. A single treatment lasts for five minutes and is neither dangerous nor painful. A local anaesthetic is all that is needed. Trials carried out on cattle in the UK have confirmed that the method can be utilized without discomfort. Now it is the turn of Australian sheep with digestive problems, which will give the scientists a better understanding of the therapeutic effects of the method. Within ten years this type of treatment could be a reality in Norwegian hospitals. But remember: green muscles are just for the animals!

Contact: Olav Storstrøm,
SINTEF Electronics and Cybernetics,
Dept. of Instrumentation.
Tel: +47 22 06 76 99
Email: Olav.Storstrom@ecy.sintef.no