The 'Berlin patient' is an HIV-positive man who developed acute myeloid leukaemia, received successful treatment and subsequently experienced a relapse in 2007 that required a transplant of stem cells.
"Our results strongly suggest that cure of HIV has been achieved in this patient," said the study in the peer-reviewed journal Blood, a publication of the American Society of Hematology.
Before the stem cell transplant the patient received chemotherapy treatment that destroyed most immune cells and total body irradiation, and also received immunosuppressive drugs to prevent rejection of the stem cells.
Antiretroviral therapy was halted on the day of the transplant, and the patient had to receive a second stem cell transplant 13 days after the first one, due to a further relapse of leukaemia.
The patient continued to receive immunosuppressive treatment to prevent rejection for 38 months, and at 5, 24 and 29 months post-transplant colon biopsies were taken to investigate possible graft-versus-host disease in the intestine. At each investigation additional samples were taken to check for signs of HIV infection in the abundant immune cells of the gut wall.
One of the challenges for any approach to curing HIV infection is long-lived immune system cells, which need to be cleared before a patient can be cured. In the case of the Berlin patient CCR5-bearing macrophages could not be detected after 38 months, suggesting that chemotherapy had destroyed these longer-lived cells, and that they had also been replaced by donor cells.
- While the highly lethal technique used on the man known as the "Berlin Patient" would not work for most of the 33 million people with HIV worldwide, scientists say the research shows important progress toward a universal cure.
"Our results strongly suggest that cure of HIV has been achieved in this patient," said the study in the peer-reviewed journal Blood, a publication of the American Society of Hematology.Before the stem cell transplant the patient received chemotherapy treatment that destroyed most immune cells and total body irradiation, and also received immunosuppressive drugs to prevent rejection of the stem cells.
Antiretroviral therapy was halted on the day of the transplant, and the patient had to receive a second stem cell transplant 13 days after the first one, due to a further relapse of leukaemia.
The patient continued to receive immunosuppressive treatment to prevent rejection for 38 months, and at 5, 24 and 29 months post-transplant colon biopsies were taken to investigate possible graft-versus-host disease in the intestine. At each investigation additional samples were taken to check for signs of HIV infection in the abundant immune cells of the gut wall.
One of the challenges for any approach to curing HIV infection is long-lived immune system cells, which need to be cleared before a patient can be cured. In the case of the Berlin patient CCR5-bearing macrophages could not be detected after 38 months, suggesting that chemotherapy had destroyed these longer-lived cells, and that they had also been replaced by donor cells.The German researchers and San Francisco-based immunologist Professor Jay Levy believe that the findings point to the importance of suppressing the production of CCR5-bearing cells, either through transplants or gene therapy.
