As reported in Emily’s news roundup, an American patient in Germany may have been cured of HIV while undergoing a stem cell transplant to treat his leukemia. The doctors
selected a donor with "a naturally occurring gene mutation" that blocks the
CCR5 receptor, "which is normally found on the surface of T cells, the type of
immune system cells attacked by HIV." The fact that one of the donors had the
mutation was pure luck – it is found only in "one to three percent of white
populations of European descent."

Unfortunately, the complexities, dangers, costs, and sheer
luck involved mean this treatment isn’t a viable means to eliminate AIDS
worldwide (about 1/3 of the people die during these types of stem cell
transplants).

CNN’s Sanjay Gupta’s blog outlines why we can’t call it a
cure. (Gupta will soon be Surgeon General for the Obama administration):

1. Even though their tests
do not show a presence of HIV in his system, doesn’t mean it’s not there. This
virus is known for hiding well and popping up later. It’s been seen before in
patients taking anti-retroviral drugs. It is possible that if more
sophisticated tests were used on this patient, they would detect the virus that
is still in his body. So it’s still not entirely clear that he is HIV-free.

2. The chances of finding
a bone marrow donor with two copies of this genetic mutation for everyone one
of the 33 million people worldwide living with HIV or AIDS is not realistic
because only one percent of Caucasians and zero percent of African Americans or
Asians have this particular genetic mutation.

3. Bone marrow transplants
are dangerous for patients. Before they can get the donated stem cells that
will replace their own, they have to take strong chemotherapy to destroy their
own bone marrow – leaving them without an immune system to fight off any
disease – until the transplanted bone marrow can make new blood cells. Plus
patients run the risk of rejecting the new cells, which means they have to take
immune-suppressing drugs for the rest of their life.

4. Bone marrow transplants
are very expensive and not an option for many people living with this disease
around the world.

 

Despite these caveats, one can’t help but feel this is good
news (and at least this cure isn’t a scam). Our government’s policy on stem cell research is evolving,
thankfully, so there’s still plenty to be optimistic about.