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First woman cured of HIV after stem cell transplant******
A US patient with leukemia hasbecome the first woman and the third person to date to be curedof HIV after receiving a stem cell transplant from a donor whowas naturally resistant to the virus that causes AIDS,researchers reported on Tuesday.
The case of a middle-aged woman of mixed races, presented atthe Conference on Retroviruses and Opportunistic Infections inDenver, is also the first involving umbilical cord blood, anewer approach that may make the treatment available to morepeople.
Since receiving the cord blood to treat her acute myeloidleukemia – a cancer that starts in blood-forming cells in thebone marrow – the woman has been in remission and free of thevirus for 14 months, without the need for potent HIV treatmentsknown as antiretroviral therapy.
The two prior cases occurred in males – one white and oneLatino – who had received adult stem cells, which are morefrequently used in bone marrow transplants.
"This is now the third report of a cure in this setting, andthe first in a woman living with HIV," Sharon Lewin,president-elect of the International AIDS Society, said in astatement.
The case is part of a larger US-backed study led by Dr Yvonne Bryson of the University of California Los Angeles(UCLA), and Dr Deborah Persaud of Johns Hopkins University inBaltimore. It aims to follow 25 people with HIV who undergo atransplant with stem cells taken from umbilical cord blood forthe treatment of cancer and other serious conditions.
Patients in the trial first undergo chemotherapy to kill offthe cancerous immune cells. Doctors then transplant stem cellsfrom individuals with a specific genetic mutation in which theylack receptors used by the virus to infect cells.
Scientists believe these individuals then develop an immunesystem resistant to HIV.
Lewin said bone marrow transplants are not a viable strategyto cure most people living with HIV. But the report "confirmsthat a cure for HIV is possible and further strengthens usinggene therapy as a viable strategy for an HIV cure," she said.
The study suggests that an important element to the successis the transplantation of HIV-resistant cells. Previously,scientists believed that a common stem cell transplant sideeffect called graft-vs-host disease, in which the donorimmune system attacks the recipient's immune system, played arole in a possible cure.
"Taken together, these three cases of a cure post stem celltransplant all help in teasing out the various components of thetransplant that were absolutely key to a cure," Lewin said.