German haematologist Gero Hütteof the Charité Universitätsmedizin in Berlin proposed and experimented a new treatment which may have cured the patient duly from Leukemia and HIV. The procedure was performed two years ago and there is still no relapse of the virus and the dosage of antiretroviral drugs has been stopped. The patient in consideration had stopped responding to chemotherapy and so a transplant was of utmost importance. Dr Hütter took this transplant to the next level by transplanting bone marrow stem cells from a donor with mutation in CCR5 gene. A 32 base pair (bp) deletion mutation within the coding region of the CCR5 gene has been associated with resistance to HIV-1 infection. This gene is responsible for encoding the receptor used by the HIV virus to enter cells. A short mutation in this gene is present in about 1% of European population and people with such mutation are less likely to contract this disease.
Skeptics however do not completely believe in this procedure theorizing that, this was one successfully attempt of the many experiments being conducted on similar lines. Some believe that virus might relapse and may be dormant in some cells like brain or heart which are not feasible to test. Also there is another strain which does not use the CCR5 medium of entry. Also this mutation is present in only 1% of European population and is very rarely observed in African population where the disease is rampant. There have been very less studies pertaining to Asian populations.
Pharmaceutical approaches have also been suggested and there is a drug in existence developed by Pfizer called maraviroc which targets CCR5, preventing binding however the HIV virus still finds a way around this competitive binding. Gene therapy has also been implemented by trying to remove the gene itself and Phase I trials have been launched by Sangamo BioSciences.
Though the technique has many disadvantages it is still a huge step towards curing of HIV.
Reference (http://www.nature.com/news/2009/090211/full/news.2009.93.html)
Image(http://s.wsj.net/public/resources/images/NA-AT825_CURE_NS_20081106180821.gif)
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