[Delayed development of chimerism following T-cell depleted bone marrow transplantation]

Comparison of cytogenetic chimaerism was performed in two children after bone marrow transplantation (bmt) with resp. without T-cell depletion for ANLL. It showed a marked delay of full bone marrow function in the patient with a T-depleted graft. Host type bone marrow cells persisted over many months, whereas they disappeared quickly when undepleted marrow was transplanted. Donor-T-cells apparently interact with remaining host cells and thus they might more efficiently eliminate leukaemia. Therefore total removal of T-cells from the graft seems risky in bmt for leukaemia.