HIV is a multifarious, shape-shifting foe. The RNA of two HIV viruses in two different people may differ by as much as 30 percent. That’s why developing a vaccine has been so difficult: A traditional vaccine might teach the body to go after a single form, but HIV’s variants are so different that the immune system won’t recognize it.
SFI External Professor Bette Korber (Los Alamos National Laboratory) and her team may have created a vaccine that could teach the immune system to wipe out many different forms of the virus. They’ve done so by turning HIV’s chief weapon, its rapid evolution, against it.
Their approach has been to design artificial proteins that are a kind of mosaic, put together from pieces of natural proteins produced by all the different strains. Then, if the body learns to kill off cells that produce any bits of that artificial protein, it may be able to protect against the full variety of HIV viruses.
The tricky part is to put the bits together in a way that still looks to the immune system like a real HIV protein, says Korber. “To do that, we evolved the virus in the same way it evolves itself in people.”
Their petri dish was a computer. They started with a database of all known natural HIV proteins and then “mated” them by swapping parts. Next, they performed an artificial natural selection: The computer chopped each protein up as the body would, and if the resulting bits commonly occur in natural HIV proteins, the protein was considered highly fit. They then “bred” the high-scoring proteins more often than the low-scoring ones. After many generations, the highest-scoring set of proteins was chosen for the vaccine.
Trials of the vaccine in monkeys have been promising. This year, the vaccine will go into Phase 1 clinical trials in humans.
Read the full story in the 2012 SFI Bulletin
Read the article in the SFI Update (March-April 2012)
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