We've talked here before about the importance of the protein CCR5 in HIV/AIDS treatment research. CCR5 is a protein on the surface of immune cells. Some people have a genetic mutation, called Delta-32, which alters how that protein works, how often it appears, or changes its structure. People with the mutation have immunity to some strains of HIV, the virus that causes AIDS.
CCR5 is the key to the Berlin Patient—Timothy Ray Brown—who, until recently, was the only person to ever be cured of AIDS. Brown received bone marrow transplants from people who had the Delta-32 mutation. His body has been HIV-free for five years. And, last week, researchers announced that two other people successfully received the same treatment.
But here's the thing, until today, I didn't totally understand how the connection between CCR5, Delta-32, and HIV worked. There's a story (and some great digital illustrations) on NPR's Shots blog that makes the situation much more clear. HIV, apparently, have little spikes all over its surface. These spikes are how the virus injects itself into cells.
When it bumps into a T cell, a finger-like projection on the cell's surface, called CCR5, pushes down on the spike. This interaction pops open the HIV and releases the infectious genes into the cell. A gene therapy could protect T cells by inactivating the CCR5 gene.
Great "A-ha!" moment for me. Read the rest of the story and look at the illustrations. It'll make some thing make a lot more sense.