image: Some HIV-infected cells clonally expand. When HIV infects a cell, a DNA copy of the viral genetic information is inserted into host DNA. This means, as long as an HIV infected cell lives, it will carry a copy of viral genetic information, and if the infected parent cell divides, all its descendants will also be infected and will carry a copy of the inserted viral DNA (provirus) at the same location in the host DNA as the parent cell. In an untreated patient, most HIV infected cells die within one or two days. A small fraction of the infected cells are long-lived. Successfully treating a patient with combination antiretroviral therapy (cART) prevents any additional cells from becoming infected, and all of the short-lived infected cells die. Some of the long-lived infected cells also die; however, some long-lived cells persist in patients, which prevents patients from being cured. We show that some of the infected cells can grow and divide, and that some of these expanded clones of infected cells, which can be identified by the location of the provirus in the host DNA, can persist for more than 10 years in patients. Thus, any strategy that is developed to cure an HIV-infected patient needs to be able not only to block viral replication, but must also block the replication of infected cells. This image relates to a paper that appeared in the 26 June, 2014, issue of Science Express, published by AAAS. The paper, Frank Maldarelli at the National Cancer Institute in Frederick, Md., and colleagues was titled, "Specific HIV integration sites are linked to clonal expansion and persistence of infected cells." view more
Credit: [Image courtesy of NCI HIV Drug Resistance Program]