Bone marrow repopulation capacity after transplantation of lymphocyte-depleted allogeneic bone marrow using counterflow centrifugation.

Bone marrow from six allogeneic HLA-matched and MCL nonreactive siblings was fractionated by means of isopycnic flotation centrifugation and subsequent counterflow centrifugation. The low density fraction (d less than or equal to 1.070 g/ml) obtained by IFC contained 20% of the nucleated cells and more than 90% of the myeloid and erythroid progenitors. The putative stem cell fraction obtained by CC showed a satisfactory recovery (88%) of the CFU-GM and BFU-E and only 3.5% of the original number of T lymphocytes. Bone marrow repopulation capacity was not impaired in comparison with a comparable group of patients. Despite the average high age of this group (29.6 years), only one of the four evaluable patients developed graft-versus-host disease.