Bone marrow cell dose and kinetics of recovery following allogeneic marrow transplantation in man.

In 50 patients transplanted for acute or chronic leukemia we studied the correlation between the number of infused bone marrow cells/kg recipient body weight and the time needed for engraftment. Engraftment was arbitrarily defined as the first day of 1 X 10(9) leukocytes/l and of 20 X 10(9) reticulocytes/l after the posttransplantation nadir. There is a negative non-linear correlation between the duration of leukopenia following marrow transplantation and the amount of transfused nucleated cells (p = 0.01). Since the incidence of infectious or hemorrhagic complications depends directly on the duration of aplasia it is justifiable to give a maximal cell dose.