Jay Johnson knows that, so far, he has truly beaten the odds.
"When I got diagnosed back in '91, it was a death sentence," Johnson said.
Johnson, now 54, knows he's lucky. For decades, a combination of anti-retroviral drugs has kept the HIV virus at bay.
"Nobody wants to live with this. They really do not," said Johnson.
Researchers have found a way to control HIV without the use of drugs by doctoring a patient's cells to resist infection. The target is one protein on the surface of white blood cells called a CCR-5 receptor.
"People without CCR-5, they are resistant to HIV, so what we do, is we try to take patients who have HIV infection and remove the CCR-5," said Dr. Pablo Tebas, infectious disease specialist at the University of Pennsylvania.
Penn researchers have taken white blood cells from patients and modified them with a specially designed molecule called a zinc finger nuclease. It causes mutation that reduces CCR-5 on the surfaces of the cells; without it, the HIV cannot enter.
"This is like a cruise missile specifically directed to this one gene in all of the 23,000 genes in the human genome," said Bruce Levine, pathologist at the University of Pennsylvania.
The modified cells are reproduced in the lab without the CCR-5, frozen, and then infused back into the patient.
"The cells are grown for 10 days, the testing takes a few more days, so we can go what we call vein to vein in about two to three weeks," said Levine.
When Johnson's doctor approached him about testing the zinc finger procedure, he agreed almost immediately.
"It will be amazing if one day I can say I'm HIV negative again," Johnson said.
In most of the patients, doctors noted a dramatic spike in the modified cells one week after the infusion. They also detected modified cells in lymph tissue, suggesting the cells were functioning normally.
Researchers said this is not a cure for HIV, but one step in a combination that may someday make the virus obsolete.
"That's the next challenge. That's the Holy Grail that people that are doing research with HIV are going after," Tebas said.
"Almost 30 years later and I am still here, and now they're talking about a possible cure. It's amazing," said Johnson.
Researchers said some of the patients who went off their normal antiretroviral drugs completely during the gene therapy retained lower amounts of the HIV in their systems, including one patient whose HIV levels became undetectable.
Researchers said this small phase-one study proved this treatment is safe for patients. Scientists from Albert Einstein College of Medicine and Sangamo Biosciences, which developed the zinc finger technology, also authored the study.
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