The man received bone marrow from a donor who had natural resistance to HIV infection; this was due to a genetic profile which led to the CCR5 co-receptor being absent from his cells. The most common variety of HIV uses CCR5 as its ‘docking station’, attaching to it in order to enter and infect CD4 cells, and people with this mutation are almost completely protected against infection.
The case was first reported at the 2008 Conference on Retroviruses and Opportunistic Infections in Boston, and Berlin doctors subsequently published a detailed case history in the New England Journal of Medicine in February 2009.
They have now published a follow-up report in the journal Blood, arguing that based on the results of extensive tests, “It is reasonable to conclude that cure of HIV infection has been achieved in this patient.”"
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