A 53-year-old from Düsseldorf in Germany has become the third person in the world to be completely cured of HIV following a stem cell transplant using donor cells with a particular genetic mutation.
Allogeneic hematopoietic stem cell transplantation – the scientific term for a bone marrow transplant – has been shown to substantially reduce the viral reservoir, the dormant HIV inside cells that can be reactivated if ART is stopped.
In 2013, he received a stem cell transplant, primarily as a treatment for his AML. The transplanted stem cells were chosen for a particular mutation found on the CCR5 gene.
The CCR5 co-receptor on the body’s immune cells plays an important role in HIV infection, acting as a “Docking site” through which HIV can enter the cell.
A homozygous mutation of the CCR5 gene, the CR5Δ32/Δ32 mutation, removes the docking site in both copies of the gene, preventing the virus’ entry into the cell and leading to widespread HIV resistance.
The patient is in complete remission from both AML and HIV. “After our intensive research, we can now confirm that it is fundamentally possible to stop the replication of the HI virus in the long term by combining two essential methods. This is on the one hand the extensive emptying of the virus reservoir in long-lived immune cells and on the other hand the transfer of the HIV resistance of the donor immune system to the recipient,” said Dr Björn-Erik Ole Jensen, the study’s lead author.
The study demonstrates the important progress made in the fight against HIV. The development of gene editing technology such as CRISPR could mean that the kind of stem cells transplanted into the Düsseldorf patient are able to be created in a laboratory rather than harvested from donors.