Scientists Get First Good Look At AIDS Virus' Surface

Newswise -- A team of scientists at Florida State University has gotten the first detailed look at the surface of the virus that causes AIDS, taking an important step in the international effort to understand how the deadly virus works.

"Future research efforts will use this information to devise new approaches to hopefully neutralize the AIDS virus," said biology Professor Kenneth Roux, who is heading up the research. "These findings have important implications for our understanding of how the human immunodeficiency virus (HIV) is formed, how it attacks our immune system and how it evades being neutralized by antibodies."

Using electron tomography, a process similar to a CAT scan, the scientists discovered that the molecule used by HIV to attack the body's immune system is composed of three separate but identical units arranged like a boat's propeller. Scientists throughout the world previously thought that this molecule, called "gp120," was only loosely attached to the virus' surface. But Roux and his team found that the molecules are much more tightly bound to HIV and are fewer in number than initially believed.

The findings suggest that a harmless form of the virus itself may be useful in developing an AIDS vaccine that would produce antibodies to attack HIV. A vaccine containing purified forms of the molecule may also stimulate the production of antibodies to attack HIV and neutralize it, Roux said.

The team's findings were recently published in the Proceedings of the National Academy of Sciences. Roux was assisted by postdoctoral associate Ping Zhu, biology professor Kenneth Taylor, postdoctoral associate Jun Liu and researchers at the National Cancer Institute.

To provide the first comprehensive view of the HIV surface, the scientists took about 35 pictures of the virus at various angles by rotating it under an electron microscope. Next, they combined the images to make one complete 3-D picture of the virus.

Future phases of the research will include seeing how antibodies attack gp120 molecules to identify better ways to neutralize HIV and seeing how the molecules behave when they attack the T-cells that help make up the human immune system, Roux said.

AIDS killed more than 4 million people worldwide in 2001, according to the World Health Organization, which estimates that about 40 million people are currently infected with HIV. Some 40,000 people in the United States become infected with HIV each year.

Roux has been involved with several research collaborations aimed at trying to develop an AIDS vaccine for nearly seven years. He and Zhu were part of an international team that announced last June the discovery of the unique structure of a human antibody that attacks HIV by attaching to the sugar coating the virus uses to mask itself from other antibodies in the immune system.

Source: Florida State University