CD8+ T cells have been found to play a role in HIV infection. HIV over time has developed many strategies to evade the host cell immune system. For example, HIV has adopted very high mutation rates to allow them to escape recognition by CD8+ T cells. They are also able to down-regulate expression of surface MHC Class I proteins of cells that they infect, in order to further evade destruction by CD8+ T cells. If CD8+ T cells cannot find, recognize and bind to infected cells, the virus will not be destroyed and will continue to grow.