Sunday, May 17, 2009

Scientists now trying to outflank HIV/AIDS virus

Great news. AP story here.

May 17th, 2009 WASHINGTON -- Like a general whose direct attacks aren't working, scientists are now trying to outflank the HIV/AIDS virus.

Unsuccessful at developing vaccines that the cause the body's natural immune system to battle the virus, researchers are testing inserting a gene into the muscle that can cause it to produce protective antibodies against HIV.

The new method worked in mice and now has proved successful in monkeys, too, they reported Sunday in the online edition of the journal Nature Medicine. The team is led by Dr. Philip R. Johnson of the Children's Hospital of Philadelphia.

That doesn't mean an AIDS vaccine for people is in the wings, Johnson said. Years of work may lie ahead before a product is ready for human use.

Nevertheless, the report was welcomed by Dr. Beatrice Hahn, an AIDS researcher the University of Alabama at Birmingham, who was not part of Johnson's team. "It basically shows there is light at the end of the tunnel," she said in a telephone interview. . . .

According to the International AIDS Vaccine Initiative, AIDS is one of the most devastating pandemics. More than 20 million people have died so far and about 33 million are living with HIV. The Center for Disease Control and Prevention last year estimated there are about 56,000 new HIV infections annually in the United States. . . .

In a decade-long effort, Johnson, K. Reed Clark of Nationwide Children's Hospital in Columbus, Ohio, and their team developed immunoadhesins, antibody-like proteins designed to attach to SIV and block it from infecting cells.

Then they needed a way to get the immunoadhesins into the cells.

The researchers selected the widely used adeno-associated virus as the carrier because it is an effective way to insert DNA into the cells of monkeys or humans. That virus was injected into muscles, where it carried the DNA of the immunoadhesins. The muscles then began producing the protective proteins. . . .

A month after administering the AAV, the nine treated monkeys were injected with SIV, as were six not treated in advance.

None of the immunized monkeys developed AIDS and only three showed any indication of SIV infection. Even a year later they had high concentrations of the protective antibodies in the blood.

All six unimmunized monkeys became infected; four died during the experiment.

The next step is moving toward human trials, Johnson said. He said he is working with the International AIDS Vaccine Initiative in hopes of getting tests in humans under way in the next few years. . . .

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