HIV latent reservoir

HIV latent reservoir

Despite the success of highly active antiretroviral therapy (HAART) in controlling HIV infection and reducing HIV-associated mortality, current drug regimens are unable to completely eradicate HIV infection. Many people on HAART achieve suppression of HIV to levels below the limit of detection of standard clinical assays for many years. However, upon withdrawal of HAART, HIV viral loads rebound quickly with a concomitant decline in CD4+ T-Cells, which, in most cases, without a resumption of treatment, leads to AIDS.

To successfully reproduce itself, HIV must convert its RNA genome to DNA, which is then imported into the host cell's nucleus and inserted into the host genome through the action of HIV integrase. Because HIV's primary cellular target, CD4+ T-Cells, function as the memory cells of the immune system, integrated HIV can remain dormant for the duration of these cell's lifetime. Memory T-Cells may survive for many years and possibly for decades. The latent HIV reservoir can be measured by co-culturing CD4+ T-Cells from infected patients with CD4+ T-Cells from uninfected donors and measuring HIV protein or RNA.^[150]

The failure of vaccine candidates to protect against HIV infection and progression to AIDS has led to a renewed focus on the biological mechanisms responsible for HIV latency. A limited period of therapy combining anti-retrovirals with drugs targeting the latent reservoir may one day allow for total eradication of HIV infection