Invisible Life of HIV Made Visible

CAITLYN SAMPLEY / AGGIE

UC Davis researchers discover how to disrupt HIV latency

By lying dormant, HIV can dodge the body’s immune system and hide from treatments. UC Davis researchers might have just found the way to bring HIV out of hiding once and for all.

“HIV latency is a unique state of HIV during its life cycle when the virus goes into hiding from the immune system,” said Guochun Jiang, a UC Davis associate project scientist. “Although the virus is present in the cells, it does not actively produce viral proteins or infectious viral particles.”

The researchers have been working on making the virus visible to the immune system so it can be targeted by immunotherapy.

“We were exploring the epigenetic mechanisms that could be exploited for disrupting HIV silence and target it for immune clearance,” said Satya Dandekar, a professor of microbiology and chair of the Department of Medical Microbiology and Immunology at UC Davis. “This led us to the identification of a new histone modification — histone crotonylation — by which HIV can be forced out of its latent state and out of hiding from the immune system. Histone crotonylation is a modification of the histone tails and occurs when  crotonyl coA gets added to lysine amino acid in histones.”

Histone modifications open up the DNA, enabling transcription factors to initiate gene expression. Histone crotonylation in particular leads to the active gene expression of HIV, making it more visible to the immune system.

The next step is to find out if reversal of HIV latency by histone crotonylation will help the immune system to eliminate infected cells,” said Dennis Hartigan-O’Connor, a UC Davis associate professor in the Department of Medical Microbiology and and Immunology and the co-investigator of this project. “We need to know if reversal of latency can have a meaningful impact on the amount of HIV in the body.”

 

Written by: Kriti Varghese — science@theaggie.org