Of
the 40 million people around the world infected with HIV, less than one per
cent have immune systems strong enough to suppress the virus for extended
periods of time. These special immune systems are known as "elite
controllers." But how do they actually fight HIV? Canadian scientists
think they've found an important clue.
Working
in collaboration with a team from the Centre de Recherche du Centre Hospitalier
de l'Université de Montréal (CRCHUM), researchers at the Laboratory of
Antiviral Immunity of Université du Québec à Trois-Rivières (UQTR) have found
that genetic mutations affecting the capsid, the structure surrounding the HIV
genome, make it possible for a protein called TRIM5α to trigger the immune
system of elite controllers.
This
discovery, recently published in PLOS Pathogens, sheds light on the role that
TRIM5α plays in the human body. In elite controllers, the protein sets off a
mechanism that protects against HIV-1, the type of HIV responsible for the
global pandemic. "In most infected individuals, TRIM5α's triggering
ability is so weak that it has no effect on the virus, but in elite
controllers, TRIM5α seems to play a role in naturally inhibiting HIV-1,"
said lead author Natacha Mérindol, a postdoctoral researcher at the UQTR lab.
There
is no vaccine or cure for HIV-1. That's why it's important to understand why
the virus is naturally inhibited in elite controllers, said Mérindol, who works
under the direction of UQTR medical biology professor Lionel Berthoux, head of
the lab, and Dr.Cécile Tremblay, a professor at Université de Montréal's
Faculty of Medicine and a clinical researcher at CRCHUM.
"Our HIV-positive
patients played an essential role in making this research possible and we would
like to thank them for their incredible generosity and availability," said
Tremblay, a microbiologist and infectious disease specialist at the CHUM.
"It's an important study that could advance research on HIV
vaccines."
Source:
University of Montreal
