Scientists Discover Key Protein Needed By Invading Hiv Aids-Causing Virus Uses Protein To Enter Immune System Cells
After a decade-long search, scientists Thursday reported finding a protein that is needed to admit the AIDS virus into human immune system cells, beginning a deadly cycle of destruction.
The discovery marks a clear advance in understanding the basic biology of the virus, knowledge that may open up new approaches to research and treatment. Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, described the finding by scientists at his institute as “a tremendous advance.”
The primary target of the virus is a receptor molecule known as CD-4, which lies embedded in the surface of certain cells. Scientists have long known that CD-4 is insufficient for infection; cells must have some other protein on their surface that the virus, HIV, exploits to effect its entry.
Scientists at the institute in Bethesda, Md., now say they have tracked down the elusive “co-factor” protein. They named it “fusin” because it helps the coat of the virus to fuse with the cell’s outer membrane and inject its genetic material into the cell.
A paper on the discovery by Dr. Edward A. Berger and his colleagues is being published Friday by the journal Science. The scientists said the finding could lead to genetically engineered mice or rabbits that are susceptible to infection with HIV and could be used to test new drugs and vaccines. In addition, the work may help explain how some people infected with the AIDS virus for years remain healthy and disease resistant, experts said.
“There is no doubt that this is the co-factor for one type of HIV and the thing that so many people have been looking for,” Fauci said in an interview. “This is not guesswork, it’s the real thing, a very elegant piece of research.”
Dr. James A. Hoxie of the University of Pennsylvania, who also studies how HIV infects cells, called the work “very exciting stuff that opens doors to several lines of research.” While the discovery of fusin does not answer all questions about the process the AIDS virus uses to enter and compromise many types of cells, he said, it knocks down a barrier that has stymied some research for years.
“It’s a huge advance,” Hoxie said in an interview. “This gives us new ways to think about what the virus does in the body.”