HIV to Cure Cystic Fibrosis?

Research conducted by geneticist Suzanne Buckley at University College in London, may provide a new treatment for the life-threatening disease cystic fibrosis. The potential cure comes from using the HIV virus to insert healthy genes into the infected patient's lungs.

Buckley is attempting to use a method known as gene therapy to place new, disease-free genes into the cells of people suffering from cystic fibrosis. The new healthy genes then function normally, replacing the genes that caused the disease.

Cystic fibrosis is an inherited disease that causes mucus to fill the lungs. The disease is life-threatening and people who suffer from the disease rarely live past their mid-30s.

According to the Mayo Clinic, cystic fibrosis affects the cells that produce mucus, sweat, saliva and digestive juices. Normally, these secretions are thin and slippery, but in cystic fibrosis, a defective gene causes the secretions to become thick and sticky. Instead of acting as a lubricant, the secretions plug up tubes, ducts and passageways, especially in the pancreas and lungs.

People infected with the defective cystic fibrosis gene often live difficult and challenging lives. The degree of severity of the disease varies, but for many, onset begins as a newborn. Patients must undergo a complicated regimen of treatment that includes drugs that help thin the thick mucus that is being secreted into the lungs, bronchodilators such as Proventil to open air passages, and the physical removal of the mucus trapped in their lungs.

Patients with cystic fibrosis are also at increase risk for pneumonia and other bacterial infections. In severe cases lung transplants are often needed to save the lives of infected patients.

The new method of treatment proposed by Buckley could potentially bypass the painful and difficult treatment of the effects of cystic fibrosis by preventing the disease from manifestation.

Gene therapy consists of inserting healthy genes into cells that contain diseased genes. The new, healthy genes can then replace the diseased genes and hopefully heal the damaged cells. To get the new, healthy genes into the cells a virus that has been modified by scientists is used. Instead of entering the cells, replicating, and killing them as a normal virus would do, the modified virus will enter the cell and release the new, healthy gene.

In the case of cystic fibrosis, the virus would enter lung tissue and other cells that use the defective cystic fibrosis gene. The virus would release normal, healthy, copies of the gene that would be incorporated into the cells. The new genes would then be used by the cells instead of the defective gene. This would cause the lungs and other tissues to act normally and not release the thick, sticky mucus that is associated with cystic fibrosis.

Research conducted by Buckley uses the HIV virus. HIV is a member of a class of viruses known as retroviruses. These viruses are particularly useful for gene therapy treatments due to their ability to insert genes permanently into the DNA code of the target cell. Thus far, Buckley's research has only been tested in mice.

Gene therapy has been used as an experimental technique since 1990, however no procedures have yet to be cleared by the FDA. In 1999 an 18 year old boy, Jessie Gelsinger, died from complications following gene therapy treatments. The potential for gene therapy to treat and possibly cure diseases is still promising, although more research and clinical trials are needed.

Buckley is presenting her work this week at the British Society for Gene Therapy conference in Warwick, Great Britain.

Sources: The Guardian

Mayo Clinic