Graft-versus-host disease (GVHD) may occur after the T-cell infusion. GVHD occurs when donor cells attack the cells of the person receiving the stem cell transplant. If GVHD occurs, you will be given standard drugs that may help control GVHD. You may ask the study staff for information about how the drugs are given and their risks. You cannot continue to receive the study drug until the GVHD is controlled. The study doctor will discuss this with you.