Gene editing, or the process of making specific changes to DNA, is already helping cancer patients and people with certain inherited diseases. The technology may eventually lead to a cure for AIDS.
John Causey tested positive for HIV nearly three decades ago. The Greater Cincinnati man has stayed alive by medication; however, the chronic infection and inflammation remain. There is no cure.
Causey was happy to sign up for the TRAILBLAZER clinical trial, or "T-Cell Reinfusion After Interfering With Lymphocyte Binding Location of AIDS Virus Through Zinc-finger-nuclease Elimination of CCR5 Receptors." It's a collaboration between the University of Cincinnati, Case Western Reserve and the University of California San Francisco.
The scientists are trying to figure out if there's a way to eliminate or reduce the amount of HIV in a patient's body. First they have to stop it from reproducing itself, as Dr. Carl Fichtenbaum, professor in the Division of Infectious Diseases at UC, explains.
"There's cells that have on the surface of them a receptor, much like a lock on the door, and those door locks are very specific for HIV," he says. "HIV has the key for that. What we're really trying to do is change those receptors so HIV can't get in."
How They Do It
They do that by getting blood from patients and then creating a mutation so the receptor, the CCR5 gene, can't get into specific white blood cells. This is accomplished with a virus. Researchers insert a homing device and instruct it to cut out the CCR5 gene. This makes a hole and then the two ends are rejoined using a different enzyme. The re-engineered blood goes back into the patient.
After the blood infusion, scientists hope 15% of cells in the blood stream will be these new cells and they will stabilize over a couple of years without HIV.
Where Did This Idea Come From?
According to Fichtenbaum, "The theory behind this really comes from a couple of patients who had bone marrow transplants because they had leukemia and HIV and those people were successful in having their HIV controlled because the cells that they got back into their body didn't have this CCR5 gene."
AIDS patient Causey says the study is one step closer to a cure. "If my research can help someone else then I'm all for it."
Thirty patients will be enrolled over the next two years and then followed for two additional years. The nearly $11 million in funding for the study comes from the National Institutes of Health.