John Barton, an assistant professor of physics and astronomy and an expert in statistical physics and evolutionary dynamics, is a coauthor on a study published in the Proceedings of the National Academy of Sciences that examines how latent HIV viruses – viruses that are inactive and “hiding” within cells – relate to the viruses that restart active infection when patients cease drug treatment.
“Despite using multiple experimental methods to try to identify latently infected cells, we were unable to find rebound viruses – the ones that restart active infection – that were genetically identical to the latent ones observed before the patients in the study ceased drug treatment,” said Barton, who came to UCR in January 2018 from the Massachusetts Institute of Technology. “In some case, however, the rebound viruses appear to be recombinants – genetic mixtures of latent viruses we observed.”
Barton explained that cells that are latently infected with HIV, collectively known as the “latent reservoir,” cannot be eliminated by current drug therapies and present the major barrier to curing HIV.
“Our work shows, surprisingly, that the source of rebound viruses is not easy to identify from measurements of the latent reservoir,” he added. “It suggests, however, that recombination occurs frequently during rebound. It is not yet clear how we could use this information to help design therapies to eliminate the latent reservoir, but our findings provide some directions for future investigation.”
Next, the team plans to explore why rebound viruses appear so often to be recombinants, and why they often appear to be different from viruses observed in the latent reservoir.
“Resolving these questions might tell us more about how latently infected cells, and outgrowing viruses, behave within the host,” Barton said.
The lead author of the research paper is at The Rockefeller University, NY.
–Iqbal Pittalwala