Rutgers scientists have taken a major step towards AIDS research by creating an HIV vaccine that shows promise in stopping an unusually diverse set of HIV isolates or varieties.
AIDS researchers Gail Ferstandig Arnold and Eddy Arnold and their colleagues took a piece of HIV that is involved with helping the virus enter cells, put it on the surface of a common cold virus, and then immunized animals with it.
They found that the animals made antibodies that could stop an unusually diverse set of HIV isolates or varieties.
The researchers' approach was to identify a part of the AIDS virus that is crucial to its viability, something the virus needs in order to complete its life cycle, and then target its weakness.
"The part that we targeted plays a role in the ability of HIV to enter cells, and is common to most HIV varieties. That is a mechanism that would not be easy for the virus to reinvent on the fly, so it turns out to be a really helpful target," said Gail Ferstandig Arnold.
While most vaccines are actually made from the pathogen itself, employing weakened or inactivated organisms to stimulate antibody production, HIV is just too dangerous to use as the basis for a vaccine vehicle.
Thus, the husband-wife duo used the relatively innocuous cold-causing rhinovirus and attached the target portion of the HIV.
This must be done in a way that maintains the HIV part's shape so that when the immune system sees it, it will actually mount an immune response as it would to the real HIV.
"The idea is to trick the immune system into thinking it is acting upon HIV before the virus shows actually shows up on the scene," said Eddy Arnold.
The researchers aimed to take a small piece of the HIV out of its native context, put it in a completely different system (rhinovirus), and have it look the same and act the same.
Using recombinant engineering, the research team developed a method to systematically test millions of varied presentations of the HIV segment with the rhinovirus.
They tried millions of different variations on how to graft (or splice) one onto the other, creating what are called combinatorial libraries.
"It's like the lottery. The more tickets you buy the better chance you have of winning," said Eddy Arnold.
"The really exciting part is that we were able to find viruses that could elicit antibodies against a huge variety of isolates of HIV. That is an immense step and a very important step," said Gail Ferstandig Arnold.
The study has been published in the Journal of Virology.