An HIV-infected man who received stem cell treatment for leukemia from a donor with natural resistance to HIV infection appears to have been cured of HIV, according to a report on the NAM aidsmap website. The treatment, which was carried out in 2007, opens the possibility of a cure for HIV infection through the use of genetically engineered stem cells.
The donor who provided the bone marrow for the transplant had a natural resistance to HIV infection due to the absence of the CCR5 co-receptor from his cells. HIV most commonly uses CCR5 as a “docking station” to enter its target CD4 cells and carriers of a genetic mutation of a portion of the CCR5 gene called CCR5-delta 32 homozygosity have a reduced risk of becoming infected with HIV.
For a period of 38 months after the stem cell transplant the patient continued to receive immunosuppressive treatment to prevent rejection of the stem cells. During this time the donor CD4 cells repopulated the mucosal immune system of the patient’s gut, accompanied by the complete disappearance of host CD4 cells. After two years the patient had the CD4 count of a healthy adult of the same age but no detectable HIV infection.
The case was first reported at the 2008 Conference on Retroviruses and Opportunistic Infections in Boston. Berlin doctors also published a detailed case history in the New England Journal of Medicine in February 2009 and have now published a follow-up report in the journal Blood saying, “It is reasonable to conclude that cure of HIV infection has been achieved in this patient.”