 Transplant patients will undergo a stem cell transplant. The cells are infused through a catheter placed in a vein for the procedure. Depending on the patient s requirements, the infusion may or may not include red blood cells and may or may not contain DMSO. Healthy volunteers undergo a 4-hour saline infusion. The saline water mixed with salt is infused through a catheter plastic tube placed in a vein in the arm. In addition, all participants have the following tests and procedures: 