By Anna Nina Chua
Philippine Science High School
Another discovery is out to break traditional methods in medicine. Before, experimental treatment for AIDS, cancer, and other inherited genetic diseases were done through gene therapy. Gene theraphy replaces defective genes with working copies or adds genes that make cells better at fighting diseases.
Usually, gene therapy trials use viruses to deliver genes to a patient's cells. Cells reproduce by splicing themselves, so this causes problems. To counter this, the viruses are crippled.
Crippling viruses seemed to have worked in treating severe combined immunodeficiency, but, in other cases the viruses have provoked inflammation and an immune response that destroyed both the virus and the cell to which it delivered genes, and some even endanger the cell's chromosomes.
So, instead of using some fancy virus, why not blast the genes into cells with a gun? that's the approach taken by cancer immunologist Wenn Sun of Northwestern Univ. and her colleague, Dr. Yang. Actually, this is not the type of gun we usually see. They've used a special type of gun powered by pressurized helium to fire microscopic bullets, coated with genes into skin cells surrounding tumors in mice. The cells then produce more of what the gene called for: cytokines, which are messenger molecules that circulate in the blood and activate immunecells
In any case, she and Yang have found that a week of gene shots, three to five times a day not only shrinks the tumors but lenghtens the lives of mice. Unlike viruses, the gene bullets don't seem to cause inflammation, and the genes they carry aren't permanently integrated into the cells DNA- their effects last only for a few days or weeks. That's a disadvantage when it comes to treating inherited diseases, but it means that diseases like cancer can be treated with less risks of side effects . Once the FDA approves the dna gun as a medical device , Sun and Yang hope to aim it at human tumors, particularly those beyond the reach of a scalpel.
Whoever thought a gun could be used to save lives?