In three of these six people, no traces of infectious virus could be found even after screening up to 360 million resting CD4 T-cells. Further tests of lymphoid tissue samples taken of the lymph nodes of two of these three people also failed to detect any infectious viral particles. After three weeks off all drugs, the virus had not rebounded in these three individuals. But he said the results were very encouraging. Before going off therapy, he was taking the cancer drug hydroxyurea as part of his drug regimen.
Research is ongoing to measure hydroxyurea's effectiveness against latently-infected cells.
HIV's First Steps Much of the groundbreaking work on HIV reservoirs was done in the early 90s by Ashley Haase, a leading virologist at the University of Minnesota, who has pioneered new techniques to measure latent HIV infection in tissue compartments. As predicted, the virus infects the cells that establish latent SIV reservoirs within a matter of hours and days. By studying how the immune responses of chimps control SIV, we might mimic that protection in humans. In a recent meeting in Delaware, Haase presented new data on sexual transmission of SIV during acute infection. In one study, the virus first targeted the endocervical region of the female genital tract in primates, and by day three, had infected lymphocytes and other cells in the lamina propia, a layer of cells underneath the epithelial cell layer of the cervix and vagina.