When the HIV virus infects a human immune cell, that cell may protect itself from complete exhaustion by becoming dormant. Montreal researchers have now devised the cellular equivalent of “smelling salts” to revive sleeping immune cells so they may fight another day.
“The cell’s reaction to invasion may seem illogical, but if the body does not take time out it will burn out,” says one of the researchers, Dr. Jean-Pierre Routy, a physician in the Division of Hematology and Immunodeficiency at the McGill University Health Centre and an associate professor of medicine at McGill University. “We can actually ‘kill’ ourselves by fighting too much.” This happens not just with AIDS, but also with other diseases like tuberculosis and cancer.
The overexpression of a protein called PD-1 triggers cell dormancy. By shutting down the expression of PD-1, the researchers were able to revive human cells in the laboratory. Once revived, the cells resumed fighting HIV infection, and evidence suggested they resisted the virus more effectively than before.
“It is important to keep this work in perspective, however,” says Routy. “This is the first time we have managed to get human cells to fight HIV, but we now need to take this laboratory achievement and repeat it in the human body.”
This research was funded by Genome Canada, Génome Québec, the National Institutes of Health, the Canadian Institutes of Health Research, the Canada Foundation for Innovation and the Réseau SIDA et Maladies infectieuses of the Fonds de la recherche en santé du Québec.