INCLUSION CRITERIA:
Family members of patients admitted to NHLBI allogeneic BMT protocols for hematological malignancy or solid tumors .
Age 18-65 .
HLA type is determined in the course of searching for a donor, or parent of patient (obligate haplotype match) will be included.
HLA 3/6, 4/6, 5/6, 6/6 match with patient will be included.
Research apheresis must be available from patient.
Venous access suitable for apheresis using antecubital veins.
Signed consent .
EXCLUSION CRITERIA:
Less than 18 or greater than 65.
Pregnancy or lactation.
HLA type unknown.
III Volunteer not a parent of patient.
More than one haplotype mismatch with patient .
Venous access inadequate.
Research apheresis available from patient.