In the thirty years since HIV forced itself into the world’s consciousness, the goal has become to find a cure for the disease. It almost seemed inevitable that a vaccine or cure would be found someday, especially when it was discovered that the cause of the opportunistic infections was indeed a virus. In fact, improvements in antiretroviral therapy (ART) over the years have made it so HIV-positive people can live relatively normal lives with an undetectable viral load. his progress is important, because it brings the scientific community one step closer to finding a cure for HIV.
New hope for a cure emerged after the Berlin Patient was discovered. The patient, an HIV-positive man who also suffered from leukemia, was given a bone marrow transplant. The marrow donor was a person with a very rare genetic mutation that renders the person practically immune, or at very least highly resistant to acquiring HIV. This mutation, known as CCR5-delta-32, removes the coreceptor that HIV uses to enter the cells. Several years later, the patient is HIV-free, with no signs of the virus. Such a story is quite the medical breakthrough, but scientists and doctors have been very cautious.
The successful transplant raised questions as to whether gene therapy could help. The goal is to genetically alter cells by attempting to mimic the genetic mutation in some way. Zinc finger nucleases were developed to delete the CCR5 receptor gene from the cells, which would make those cells resistant to HIV infection. In order to test this theory, a study was conducted consisting of six patients with long persisting HIV infection. The patients had blood drawn from them and the CD4 T-cells were removed. Those cells were then given the zinc finger procedure to remove the CCR5 receptor gene.
These treated cells were then reinserted back into the patients’ bodies. The result? Five of the six patients experienced a significant CD4 cell increase, averaging about 200 cells each. This approach could make it possible for HIV-positive patients to stay off of antiretroviral therapy medication for longer periods of time. Using gene therapy is giving researchers hope that it may be the key to finding a cure for HIV. Other methods such as reducing or eliminating HIV reservoirs are being looked into as well. HIV has reached a milestone of sorts, having been the catalyst for 30 years of research in trying to slow it down or eradicate it. Progress has been made, but the quest toward a cure continues.