Inclusion Criteria:

- Patients with hematological malignancies who are undergoing evaluation for autologous
or allogeneic stem cell transplants will be eligible, if: (1)They have no circulating
neoplastic cells in the peripheral blood as assessed by routine morphology or flow
cytometry. (2)Patients with acute myeloid or lymphocytic leukemia are in complete
remission

- First-degree relatives of patients evaluated for stem cell transplantation will be
eligible if: (1) Willing to undergo testing for HIV and hepatitis B and C (free of
charge) (2) Not pregnant at time of collection of blood (3)In good general health (4)
No prior history of malignancy. (5) Age 18 years or older if donating apheresis
product. (Because of the relatively invasive nature of the leukopheresis procedure
and difficulties in obtaining consent, children <18 who are first degree relatives of
the patient will not undergo apheresis for studies on this protocol)

- Written informed consent

Exclusion Criteria:

-