NK and K cell activity in children with leukemias and aplastic anemias before and after allogeneic bone marrow transplantation

: Mononuclear leukocytes from the peripheral blood and bone-marrow of children affected with aplastic anemia and leukemia were investigated for K-cell activity (antibody-dependent cellular cytotoxicity) and NK-cell activity before and after allogenous bone-marrow transplantation. 51Cr liberation test against murine Graffi erythroblast leukemic cells covered with xenoantibodies and K-562 cells were used for identification. Strongly lowered NK- and K-cell activities could be found in aplastic anemia prior to bone-marrow transplantation. However, NK-cell activity was only lowered significantly in leukemic patients with indication of bone-marrow transplantation. K-cell and NK-cell activities normalised after bone-marrow transplantation. K-cell and NK-cell activities could be observed to be reconstituted very early after bone-marrow transplantation.