Patients who have recently been able to clear or control their acquired immune deficiency syndrome (AIDS) have renewed the interest of scientists in finding a cure for the human immunodeficiency virus (HIV) and subsequently, AIDS. The newest ideas to help generate a cure include transplants of naturally resistant stem cells or the genetic modification of immune cells to render them immune to the virus (Pollack 2011). Since people with HIV are required to take antiviral drugs to control the infection for the rest of their lives the discovery of a cure would improve countless lives and solve one of the world’s foremost health issues.
HIV is a retrovirus which attacks the cells of the human immune system, causing their inability to function. As the HIV infection advances, the immune system of the person gradually weakens, making them more vulnerable to other illnesses. The last stage of the HIV infection, AIDS, usually takes 10-15 years to reach and antiviral drugs can slow the development down even further (World Health Organisation 2012).
In the first patient, a man seemingly cleared his HIV infection through numerous bone-marrow transplants he received as leukemia treatment. The donor was one of the 1% of Northern Europeans that lack a protein, CCR5, rendering him naturally resistant to HIV. Due to the bone-marrow (stem cell) implant the patient is able to produce a resistant immune system and has been free of the virus for four years (CBS News 2011). However, this approach for a cure is unlikely due to the difficulties of finding a matching donor as well as the transplant procedure being risky and expensive. In addition, donors would be unethically ‘farmed’ for bone-marrow. Therefore this approach for a cure is highly improbable.
Scientists attempted to modify the immune cells of the second patient, eliminating the CCR5 protein, in order to make them resistant to HIV. White blood cells were removed from the body of the patient and put through gene therapy which modified the cells to produce another protein which disrupted the CCR5 protein. The treated cells were replaced into the man’s body and a month later the man stopped taking antiviral drugs as part of the experiment. Initially, the amount of HIV rose sharply, as expected, but then dropped to an undetectable level gradually while immune cell counts rose. However, the gene therapy did not work as well in 5 other patients (Pollack 2011). This approach to a cure is unproven through these patients but is still being developed, moving onto further clinical trials earlier this year (Instinct Staff 2012). This idea presents numerous problems, the main one being that each individual would have to undergo the procedure making this cure implausible at this point.
Although there is great need of a cure for HIV, with the current methods and ideas involving stem cell transplants and gene modifications, it is doubtful that a functional cure that can be used on a wide scale will be found in the near future.
- CBS News 2011, Doctors Claim to Have “functional cure” For HIV, viewed 15 March 2012, <http://www.cbsnews.com/2100-18563_162-20069146.html>
- Instinct Staff 2012, Promising "Functional" HIV Cure Moves Forward With Testing, Instinct Magazine, viewed 15 March 2012, <http://instinctmagazine.com/blogs/blog/promising-functional-hiv-cure-moves-forward-with-testing?directory=100011>
- Pollack, A 2011, New Hope Of a Cure For H.I.V., The New York Times, viewed 14 March 2012, <http://query.nytimes.com/gst/fullpage.html?res=9A02EFD61230F93AA15752C1A9679D8B63&ref=geneticengineering&pagewanted=all>
- World Health Organisation, HIV/AIDS, viewed 15 March 2012, <http://www.who.int/topics/hiv_aids/en/>