Antibody makes humanized mice immune to HIV

WASHINGTON, Feb. 11 (UPI) -- When repeatedly exposed to a common strain of HIV, mice treated with an antibody were much less likely to contract the virus than mice that were not -- researchers at the California Institute of Technology recently found.

Scientists think the unique creation and delivery of the antibody could be effective for preventing the spread of HIV among humans.

The new antibody does not operate like a traditional vaccine. A vaccine is an antigen that induces the body's immune system to generate the antibodies necessary to fight a potential infection. But while the antibody delivery method, called Vectored ImmunoProphylaxis, or VIP for short, still features an injected virus, it is only the messenger.

The virus carries special genes that are added beforehand. The virus effectively delivers these genes to the muscle tissue where they tell the body to produce the HIV neutralizing antibody VRC01.

"This procedure is extremely effective against a naturally transmitted strain and by an intravaginal infection route," explained lead researcher and Novel Laureate David Baltimore, "which is a model of how HIV is transmitted in most of the infections that occur in the world."

Of the ten mice protected with the VIP antibody treatment and then repeatedly exposed to HIV, only two became infected. All nine of the unprotected mice contracted HIV.

Mice and other animals can't normally become infected with any strand of HIV, but humanized mice, like the ones used in this experiment, are genetically modified to imitate the immune systems of humans.

The study, funded by the National Institutes of Health, was published this month in the journal Nature Medicine.

[{link:Medical Xpress"http://medicalxpress.com/news/2014-02-method-hiv-fighting-antibodies.html" target="_blank"}] [Nature Medicine]