Even with no detectable levels of HIV in the blood, HIV remains in some tissues in the body, primarily the gut tissue. HIV infects the CD4+ T-cells including in the blood and gut. The new treatment to be studied will involve removing white blood cell from the blood that contains CD4+ T-cells. The extracted CD4+ T-cells are then genetically modified by the ZFNs to be resistant to infection by HIV by removing the CCR5 gene from the surface of the CD4+ T cell where HIV enters the cell. Additional genetically modified cells are manufactured and then re-infused back into you. Researchers hope that these genetically modified cells will be resistant to infection by HIV and will be able to reproduce additional resistant CD4+ T-cells in your body.