UW News

January 6, 2000

HIV virus can alter the way genes function within days of exposure

According to a University of Washington study published in the January 2000 issue of Virology, genes involved in T-cell signaling, protein trafficking and transcriptional regulation were among the genes that displayed functional changes within three days of exposure to the HIV virus.

The study examined the level or “expression” of approximately 1,500 genes in cells that were deliberately infected with the HIV virus. “By using gene expression microarrays, we discovered cellular changes in the expression levels of at least 20 different genes by day three of our study,” said Dr. Gary K. Geiss, a senior fellow at the UW?s Department of Microbiology who directed the laboratory research.

Dr. Michael G. Katze, professor of microbiology and principal investigator for the study, said detecting changes at the cellular level could have a substantial impact on future treatments for the disease. The results published in Virology were part of a preliminary study, and the UW microbiologists intend to conduct a larger study on the impact of HIV on cellular functions.

“When a virus like HIV infects a cell, it takes over and uses the machinery of that cell to help make proteins the virus needs to replicate and live. Genes make up part of that machinery,” said Katze. “If we can learn which genes are used by the virus but not by the host cell, we may open up new ways for researchers to fight the disease.”

In the study, gene expression profiles were closely observed using cDNA microarray technology. The genes were examined prior to and after HIV exposure to determine how quickly cellular genes would be significantly influenced by viral infection. The study showed that HIV infection alters the function of a broad array of cellular genes, including some genes associated with immune system functions.

Microarray slides, also called “DNA chips,” consist of spots of DNA, and each slide can contain hundreds or even thousands of genes. Researchers can measure and observe gene expression levels to determine when genetic changes occur and how these changes influence the progression of disease.

The study is supported by grants from the National Institutes of Health. The microarray technology was provided by Amersham Pharmacia Biotech, which helped to develop a state-of-the-art microarray facility for the UW Department of Microbiology and the Washington Regional Primate Research Center.

For more information contact Dr. Roger Bumgarner at (206) 685-7307.