Recently, the man referred to as the “Dusseldorf patient” became at least the third person to have been “cured of HIV” after a bone marrow transplant carrying a specific HIV-resistant mutation.
About CCR5 Delta 32 –
- Cysteine-cysteine chemokine receptor 5 (CCR5) is a protein on the surface of white blood cells that are involved in the immune system as it acts as a receptor for chemokines.
- CCR5 is found in the cell membranes of many types of mammalian cells, including nerve cells and white blood cells.
- In humans, the CCR5 gene that encodes the CCR5 protein is located on the short (p) arm at position 21 on chromosome 3.
- Role of CCR5 — The role of CCR5 is to allow entry of chemokines into the cell—chemokines are involved in signalling the body’s inflammation response to injuries.
How does the mutation work in HIV patients?
- Various mutations of the CCR5 gene are known that result in damage to the expressed receptor.
- One of the mutant forms of the gene is CCR5-delta 32, which results from the deletion of a particular sequence of 32 base pairs.
- HIV (Human Immunodeficiency Virus) mainly attacks the CD4 immune cells in the human body, thereby reducing a person’s ability to fight off secondary infections.
- The CCR5 receptors on the surface of the CD4 immune cells act as a doorway for HIV. However, the CCR5-delta 32 mutation prevents these receptors used by the HIV from forming on the surface, effectively removing the doorway.