http://www.npr.org/b...ientific-debate
Top AIDS scientists are scratching their heads about new data from the most famous HIV patient in the world — at least to people in the AIDS community.
Timothy Ray Brown, known as the Berlin patient, is thought to be the first patient ever to be cured of HIV infection.
Brown, 45, had two bone marrow transplants in Berlin in 2007 and 2008 to treat leukemia that is apparently unrelated to his HIV infection. The blood cells for the transplants came from a donor with a genetic mutation that makes his cells immune to HIV — they lack receptors the virus needs to gain entry to cells. Details about his case were published in the New England Journal of Medicine.
The transplants appear to have snuffed out Brown's HIV infection. After an initial spike, the stubborn virus disappeared from his system — even though he is no longer taking anti-HIV drugs.
But new data presented last week in Spain raise a question about whether there are minute traces of HIV in some tissues — not whole virus capable of replicating, but pieces of viral genes.
Researchers have combed through 9 billion of Brown's cells, retrieved from his blood, lymph nodes, spinal fluid and intestinal tract. Four different labs could find no trace of HIV in his blood cells. But three groups, using tests at the very limit of detectability, think they have identified bits of HIV genetic material — two from blood plasma and one from intestinal cells.
It could be a false reading, due to laboratory contamination, scientists say. For one thing, the fragments of viral genes don't completely match those of the HIV Brown harbored before his transplants.
"Although the subject has had intermittent evidence for HIV persistence in some assays in some laboratories," the researchers wrote in a summary, "the extremely low levels of virus which were detected, while pushing the limits of sensitivity and specificity ... make it impossible to conclude that the subject remains HIV-infected."
Dr. Douglas Richman of the University of California, San Diego, who found no hint of HIV in Brown's cells, thinks the signals are due to laboratory contaminants. If you do enough runs of these ultra-sensitive tests, Richman told Science magazine's ScienceInsider blog, "you can get a signal in water for pink elephants."
Scientists at the University of California, San Francisco, who are following Brown most closely, declined to comment publicly, citing his confidentiality as a patient and research subject.
But AIDS researchers — and Brown himself, in an interview with Shots — stress that even if the new findings constitute real evidence of HIV in his system, they don't mean he's not cured. Although, it's clear the findings do raise questions about what sort of cure he has.
Scientists hoped Brown had a so-called sterilizing cure — that is, the HIV has been completely eradicated from every cell in his body.
But long and bitter experience with HIV has shown that the virus can hide out in the genes of very long-lived resting immune cells. As these latently infected cells get activated over the years, HIV might reappear in the form of the whole virus or perhaps pieces of its genes.
But if that is happening in Brown, there is no evidence that the virus is actively replicating. To do that, it would need to infect other cells and hijack their genetic machinery to crank out more virus. Since Brown's replacement immune system (from the bone marrow donor) doesn't have the entry portal HIV needs, these new viruses (if they exist in his case) can't spark a new viral conflagration.
Therefore, he may be functionally cured, even if he's not totally free of HIV.
Basically after having two bone marrow transplants, the HIV appears to have left his blood cells. There was some tiny genetic material left from the HIV, but all in all, he doesn't have any in his blood cells, thus making him "cured" of the virus.
This is causing some debates with AIDS researchers and scientists who are either baffled by this, or believe that it is a false reading from the labs. Your take on this so called "miracle"?
