
                         Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: FRIDAY, July 20, 1990                   TAG: 9007200242
SECTION: NATIONAL/INTERNATIONAL                    PAGE: A10   EDITION: METRO 
SOURCE: Newsday
DATELINE:                                 LENGTH: Medium

SCIENTISTS DISCOVER POSSIBLE PREVENTIVE TO AIDS VIRUS' SPREAD

Scientists have found a class of chemicals that completely block the ability of the AIDS virus to infect human cells in test-tube studies.

Although the work is considered very preliminary, the Harvard team describes the finding as one of "considerable therapeutic importance."

The chemicals are artificially created molecules known as CPFs. They are compounds made from synthetic versions of the amino acids proline and phenylalanine. Amino acids are the essential building blocks of proteins.

The discovery, to be reported in today's issue of Science magazine, was made by a team of immunologists, led by Dr. Steven Burakoff, and synthetic chemists, headed by Stuart Schreiber, who studied the protein in cells that the AIDS virus latches onto to enter them. Through chemical analysis they found a small segment of the cellular protein that functioned as the lock at the entry point of a cell and its counterpart, or key, on the AIDS virus, Burakoff said. The lock and key must match exactly for the AIDS virus to get into the cell.

They also found phenylalanine was part of the virus "key" and that when it was missing, the virus could not use the protein to get into the cells.

"With that information in hand, we thought it might be wise to look at a group of molecules that had phenylalanine in them," Burakoff said, to see if it might be possible to block this viral unlocking mechanism.

They then discovered that the CPFs would bind to the "key" in the AIDS virus, completely blocking the virus' ability to get into cells.

"We have evidence that it [CPF] binds very, very tightly with the virus. We've gone through 8,000 washes and [the virus] is still unable to bind" to the cellular protein, Burakoff said, indicating that the reaction is irreversible.

The chemicals are cheap, easy to make, long lasting and considered relatively harmless. For example, Nutrasweet, the popular artificial sweetener, is made from phenylalanine.

Preliminary and as-yet-unpublished research by the team shows CPFs are not toxic in mice, Burakoff said.

But he cautioned that the work "is just the first of several hurdles that have to be overcome before we try it clinically."

by CNB