It is estimated that over a million people in the U.S. are currently affected by HIV. Since its discovery, advances in treatment using combinations of anti-viral medication has vastly improved both the standard of living and lifespan of HIV patients. Though there are ongoing efforts to create a vaccine, this is proving to be a daunting challenge.
In February of 2009, a paper published in the New England Journal of Medicine took many by surprise when it discussed a case where a HIV patient treated for leukemia using a bone marrow transplant no longer had traces of the virus after the procedure. According to an article published by Reuters in December 2010, the patient is still HIV free four years after the bone marrow transplant. There is no doubt that this represents a remarkable leap forward in the fight against HIV, but before getting too excited, it is important to discuss the implications for HIV patients.
The human immunodeficiency virus (HIV) infiltrates T-cells (a type of immune cell) by gaining access through a marker on the cell surface called CCR5. In the noted case, the patient also had leukemia, which is a cancer of immune cells of the blood. During the treatment of leukemia the patients immune cells (including T-cells) were targeted and killed. Following this, a bone marrow transplant was given, however, with immune cells lacking the CCR5 receptor. After checking for HIV twenty months later there was no trace of the virus in the patient. As a result, the researchers concluded that the lack of CCR5 receptor prevented HIV from infecting the transplanted cells. Indeed, some may have heard about individuals who are resistant to HIV and the lack for the CCR5 receptor is the implicated mechanism of immunity.
Unfortunately, though this treatment is not easily replicable. Undergoing bone marrow transplantation is extremely dangerous and is not undertaken unless strongly indicated. Even if this were not the case, it is challenging to find appropriate matches for transplantation. Moreover, patients with HIV can now live a long life with medical treatment, and with current techniques it would be inadvisable to perform this method on any given HIV patient considering the likely high mortality rate. Still, the success in this case represents a large step forward in the fight against HIV.
- HIV & AIDS Statistics from around the world, from avert.org
- Long-Term Control of HIV by CCR5 Delta32/Delta32 Stem Cell Transplantation (New England Journal of Medicine, February 2009)
- German doctors declare 'cure' in HIV patient (Reuters, December 2010)
- Glowing Kittens Help in Fight Against AIDS (NPR, September 2011)