A recently released study published in The New England Journal of Medicine contends that a 42-year-old HIV patient also afflicted with leukemia has no signs of HIV in his blood after a stem cell transplant two years ago in which he received stem cells from a donor who caried a gene mutation that bears a natural resistance to HIV.
An excerpt from the study describes its findings in some detail: “The team deliberately chose a compatible donor who has a naturally occurring gene mutation that confers resistance to HIV.
The mutation cripples a receptor known as CCR5, which is normally found on the surface of T cells, the type of immune system cells attacked by HIV. The mutation is known as CCR5 delta32 and is found in 1 percent to 3 percent of white populations of European descent. HIV uses the CCR5 as a co-receptor [in addition to CD4 receptors] to latch on to and ultimately destroy immune system cells.
Since the virus can’t gain a foothold on cells that lack CCR5, people who have the [gene] mutation have natural protection [people who inherit one copy of CCR5 delta32 take
longer to get sick or develop AIDS if infected with HIV]. People with two copies [one from each parent] may not become infected at all. The stem cell donor had two copies.”
Researchers stress that the stem cell method is in its initial development and is too dangerous to be considered as a routine form of treatment for most people infected with HIV at this time. However, doctors say the findings imply that the development of safer CCR5-disabling gene therapies to be injected into an HIV positive patient’s body is possible and would help in the fight against AIDS.