T cell and NK cell mediated graft-versus-leukaemia reactivity following donor buffy coat transfusion to treat relapse after marrow transplantation for chronic myeloid leukaemia.

Two patients with chronic myeloid leukaemia in cytogenetic relapse following T lymphocyte-depleted BMT were treated with transfusions of donor buffy coat leucocytes. In both patients the marrow reverted to a completely normal karyotype and was negative for the BCR-ABL fusion gene transcript by polymerase chain reaction analysis. Before bury coat transfusion the cytotoxic T lymphocyte precursor frequency against pre-BMT patient leukaemia cells (Lk-CTLP) was lower than that agaunst pre-BMT patient PHA-transformed lymphocytes (Ly-CTLP) in both cases