In this third case, it is a man followed in Düsseldorf. As detailed the prestigious journal Nature Medicine, according to the recommendations at the time, the patient started antiretroviral treatment in 2010 which allowed him to control the HIV infection and reduce the amount of virus to undetectable levels in the blood, like most people on treatment . In 2011, this patient was diagnosed with leukemia, a cancer of the cells of the immune system located in the bone marrow. He then received chemotherapy, which allowed him to control the leukemia, but, after a relapse, he had to receive a stem cell transplant from an anonymous donor in 2013. Initially, a donor whose immunogenetic characteristics are compatible with the patient was sought. Then, in these unique cases of people living with HIV, a donor carrying the CCR5 delta-32 mutation was solicited.
“We know that the virus du VIH targets the cells of the immune system. During a bone marrow transplant, the patient’s immune cells are thus completely replaced by those of the donor, which allows the vast majority of infected cells to disappear., explains Asier Sáez-Cirión, co-lead author of the study. Moreover, the transplant itself represents a medical challenge: “First of all, it is necessary to find an immunogenically compatible donor to avoid transplant rejection. Moreover, since less than 1% of the general population carries this HIV protective mutation, it is very rare that a compatible marrow donor has this mutation. In the end, it is an exceptional situation when all these factors coincide for this transplant to be a double success in curing leukemia and HIV.”adds the researcher.
