Cell-to-cell spread of HIV permits ongoing replication despite antiretroviral therapy

Antiretroviral therapy suppresses, but does not eradicate, HIV infection. Low-level viraemia continues for life because of the persistence of treatment-resistant reservoirs of the virus. Various different types of reservoir are thought to exist. David Baltimore and colleagues use a combination of mathematical modelling and a cell culture model of HIV infection and drug treatment to propose that ongoing HIV replication can occur in the presence of drugs if the cells become infected through cell-to-cell transmission. They propose that cell-to-cell spread of virus could be a source of localized and intermittent ongoing replication, which may show little evolution, and which could contribute to replenishment of the virus reservoir and virus persistence.