Ex Vivo T-Cell Depletion of Mobilized Peripheral Blood Stem Cells Via CD34-Selection

Participation in this project will last approximately one year with follow-up exams. Before treatment can begin, stem cells will be collected from the donor (a close relative) that has been selected as the best match for the participant. White blood cells will be collected from the donor. The cells will then be mixed with a special protein, called a CD34 antibody, that binds to the stem cells, which will then be separated out from the white blood cells by a special machine- called a CliniMACS CD34 Reagent System in the laboratory. This is an investigational device that is not approved by the FDA. Although this device is not approved for use in this country, it has been in use for years and is approved in other countries. The stem cells will be collected and given fresh or they can be frozen before they will be given to the participant. On about days 28, 60, 100, 180 and 365 after the transplant, the participant will have the same tests/evaluations since the time of transplant. For patients who do not develop GvHD, they are not required to have these tests/evaluations. In addition, for purposes of the study, health-related information will be collected for a year from the time of stem cell infusion. This will be used to determine survival, relapse, infections and GvHD that may occur following transplant.