B.C. researchers have discovered a way to identify multiple strains of HIV that lay dormant in the cells of an individual.
HIV evolves continually while it is active, storing versions of itself in the DNA of infected cells that then go dormant, waiting to reactivate at some future date, like an archive of genetically unique “time bombs,” said Zabrina Brumme, director of the HIV/AIDS lab at the B.C. Centre for Excellence in HIV/AIDS.
Brad Jones, a Ph.D. student involved in the B.C. Centre for Excellence in HIV/AIDS and Simon Fraser University study, said researchers “created a highly calibrated ‘time machine’ that gives us a specific time stamp for when each dormant HIV strain originally appeared in a person.”
That allowed scientists to construct a family tree of the virus in each patient to see how it evolved over time, right from when the virus was contracted, even decades earlier.
While the discovery is a long way from a cure, this study does give scientists a clearer idea of how challenging it will be to extricate the virus from a patient’s cells.
“If you can’t identify it, you can’t cure it,” said Brumme, who was the study’s lead author.
Eliminating the virus from an individual would require a way to remove not just a single version of the virus from archive cells, but the whole evolutionary history of the virus in that patient, she said.
“Curative strategies will need to address this new study’s key findings,” said Julio Montaner, Director of the B.C. Centre for Excellence in HIV/AIDS.
Dormant versions of the virus are untreatable with antiretroviral therapy, which is why HIV treatment must be maintained for the lifetime of the patient.
“In order to eradicate HIV from a person’s body, you first need to know the characteristics of HIV in the latent reservoir,” said Western University assistant professor Art Poon, a co-author on the study.
A cure for HIV would likely require several simultaneous kinds of therapy and it would almost certainly require treatment that was personalized for individual patients, possibly based on the genomes of all the strains of HIV stored in the patient’s cells.
Author: RANDY SHORE