Seventh Person Declared Free of HIV Following Stem Cell Transplant

The first known individual to be declared HIV-free following a bone marrow transplant for blood cancer was Timothy Ray Brown, also known as the Berlin patient. Brown, along with a few others, received donor stem cells that carried a rare mutation in the gene encoding the CCR5 receptor, which most HIV strains use to enter immune cells. This led many scientists to consider targeting CCR5 as the most promising strategy for an HIV cure.

However, a new case presented at the 25th International AIDS Conference in Munich, Germany, challenges this notion. The patient, referred to as the "next Berlin patient," received stem cells from a donor who had only one copy of the mutated CCR5 gene. This means the donor's cells still expressed CCR5, but at reduced levels.

According to Sharon Lewin, an infectious-disease physician and head of The Peter Doherty Institute for Infection and Immunity in Melbourne, Australia, this case demonstrates that a potential cure for HIV is “not all about CCR5.” The findings suggest that successful HIV remission can occur even with partial CCR5 expression, thus expanding the range of potential donors for stem-cell transplants.

Although this procedure remains risky and is typically reserved for individuals with both HIV and leukemia, this discovery broadens the possibilities for treatment. Approximately 1% of people of European descent have mutations in both copies of the CCR5 gene, while around 10% have one mutated copy, potentially increasing the donor pool for similar cases.

SOURCE: https://www.scientificamerican.com/article/seventh-person-cured-of-hiv-after-stem-cell-transplant/ 

CREDITS: SCIENTIFIC AMERICAN