 In order to collect the skin fibroblasts at the very beginning of the study, and then during the study, we will perform small skin biopsies. In particular before the second shot, and then again about 1 week later, we will look for both the modified and leukemia cells that have been re-injected under the skin. We will do this by taking a skin biopsy from the place where the cells were injected. The area where the skin biopsy will be obtained will be sterilized and then numbed with a local acting agent. The skin will be removed with a tissue punch which will cut a circle of approximately 14th of an inch into the skin. The site where the skin was removed will be closed with suture, tape or stitches. The area will be covered with dry gauze and adhesive tape. These tests are to see whether the shots are killing leukemia cells and to make sure leukemia cells are not growing at the injection site. 