You are about to undergo a hematopoietic stem cell transplant (HSCT) using stem cells collected from either bone marrow or from the blood in an effort to treat your illness. These stem cells are the early blood producing cells, capable of replenishing blood formation after transplant. You have been told that one of the side effects of stem cell transplantation is that your immune system will be weak for many months after the transplant. Specifically, it is likely that the numbers of one particular type of immune cell known as the CD4 T-cell will be quite low during this time. Risks of infection during the first year after transplant, particularly during the second through 12th months, often correlate with the number of CD4 T-cells circulating in the blood.

To speed up immune recovery after transplant, a number of stem cell transplant centers have administered additional immune cells (white blood cells) from the marrow donor by transfusion. This type of infusion is usually referred to as a donor lymphocyte infusion or DLI. The major risk of DLI is that the donor’s immune cells might recognize your body as different from that of the donor and cause a problem known as graft versus host disease or GVHD. If the donor’s immune cells do attack your body, this will commonly produce skin rash, diarrhea, and liver damage and jaundice. In order to prevent this problem, the doctors at Jefferson propose to treat the DLI with an investigational drug known as L-leucyl-L-leucine methyl ester (LLME) before it is given to you. LLME is considered investigational because it has not been approved by the Food and Drug Administration (FDA) for this form of treatment or any other purpose.

This drug destroys most of the T cells capable of killing other cells, but leaves most of the CD4 T-cells intact. This research study will determine the effectiveness of giving donor cells treated with this investigational drug to improve the recovery of the immune system following stem cell transplant. Increasing numbers of cells will be given each month after transplant. If patients treated before you have shown acceptable levels of side effects, you may receive a higher starting dose of LLME treated cells, to determine whether higher doses are also well tolerated and potentially more effective or more rapidly effective.