Recent medical breakthroughs in the fight against HIV/AIDS

A group of doctors in Berlin believe that they have cured HIV in a man who underwent a stem cell transplant to treat his leukemia.

Who is doing the research?
A group of doctors at the Charite - University Medicine Berlin.

When was it discovered?
The case was originally presented at a conference in 2008. The full case history was published in the New England Journal of Medicine in February 2009. Follow-up results were published in December 2010 in the journal Blood.

Why is this groundbreaking?
Doctors believe that they have cured their patient of HIV. They have been following the case for 3 years and HIV has not reappeared in the man’s body. This case may point the way towards utilizing stem cell transplants to develop a cure for HIV.

How was the HIV infection cured? The patient in this case received a bone marrow transplant as part of his leukemia treatment. Doctors deliberately chose a stem cell donor who had a particular CD4 cell mutation.

HIV enters host cells by binding to a CD4 receptor and then interacting with either CCR5 or the CXC chemokine receptor (CXCR4). The stem cell donor did not have a CCR5 receptor on his CD4 cells. Basically, the HIV in the patient’s body was no longer able to attach and take over his CD4 cells (which is how HIV spreads in the body).

How long until treatment is available?
Even though the results of the study are very promising (i.e. it appears likely that the patient has been cured of HIV), the treatment used is not a viable cure for the vast majority of people living with HIV. If, over the long term, the HIV doesn’t resurface in the patient (i.e. it is not lurking in deposits in the body, waiting to mutate and resurface) there are two major barriers to this treatment being considered a true cure:

1. The genetic mutation present in the donor stem cells is only present in 1-3% of the Caucasian population (African Americans and Asians do not have this mutation). There are not nearly enough donors to treat the number of people living with HIV.
2. The process of undergoing stem cell transplants is risky. Before the transplant can take place, patients must undergo chemotherapy which leaves them without any immune system. Side effects, transplant rejection and even death can (and do) occur during the transplant process.

For more on this study:
Article published in the New England Journal of Medicine - retrieved December 20, 2010
Stem cell transplant has cured HIV infection in ‘Berlin patient’ says doctors, aidsmap - retrieved December 20, 2010
Man appears free of HIV after stem cell transplant, CNN Health - retrieved December 20, 2010