By Jeannie Wraight and Mariel Selbovitz MPH
In 2007, a German doctor named Gero Hutter performed a risky surgical procedure on a man with both HIV and leukemia that would result in the first person being, at least, “functionally cured” of HIV. In the years since, the details of the procedure have been well-documented, publicized and scrutinized, leaving little doubt that Timothy Ray Brown - formally known as “the Berlin Patient” - has indeed been cured of HIV. Now, six years later, doctors at the University of Minnesota will attempt a similar procedure in a child with leukemia who was born HIV positive.
Although successful, it is contended that the strategy used to cure Timothy Ray Brown cannot be used as a widespread cure for people living with HIV. Because of the unique set of circumstances, it remains unclear as to whether it can be replicated at all, even given similar circumstances.
The procedure is simply explained but fraught with danger. The immune system is destroyed by using chemotherapy and radiation, hopefully killing HIV and the cancer along with it. Blood cord cells (or in Brown’s case, bone marrow cells) from a compatible donor are then used to rebuild the immune system. In Timothy’s case, these cells were from a man with a genetic mutation that confers resistance to HIV. For the child, doctors are using cells from a newborn’s umbilical cord. This particular newborn also has CCR5-?32, the genetic HIV-resistant mutation which lacks the chemokine receptor ‘doorway’ that many HIV strains use to enter and infect a CD4-T cell. It’s the hope of doctors at the University of Minnesota that the child’s immune system will repopulate with cells that are resistant to HIV, thereby obtaining the same type of cure as Timothy Ray Brown.
After the surgery, the boy will be monitored in the hospital for 100 days while doctors wait and watch for signs of a return of leukemia and/or HIV. Unlike Timothy, the boy will keep taking antiretroviral therapy and then be taken off over the coming weeks. This procedure is not without risk! One in five people who undergo a regular blood cord transplant do not survive.
If the blood cord transplant using an umbilical cord from a newborn donor with the CCR5-?32 is successful, it may offer new hope to people who suffer from HIV and leukemia or lymphoma. For the time being, all we can do is pray and hope the child does well.
On another front, Danish scientists have publicly speculated that HDAC inhibitors can release HIV from its reservoirs and bring it to the surface of the cells. It would then be destroyed by the body's natural immune system, boosted by a vaccine. "Finding a mass-distributable and affordable cure to HIV is possible," said one of the scientists involved in the study. While offering enthusiasm, veterans of the AIDS crisis know that caution should always precede speculation. We have been here before with Remune, the HIV vaccine developed by Dr. Jonas Salk, gene therapies, IL-2 and the initiation of HAART.
The Jewish Passover Seder (supper meal) always concludes with a statement of profound spiritual longing and hope, “Next year, in Jerusalem!” Can we hope that a cure for HIV is getting that close?