[Granulocyte-macrophage progenitor cells in allogenic bone marrow transplantation: correlation of progenitor cell content and regeneration in the graft].

The amount of granuloid macrophage progenitors (CFU-GM) was studied in 16 donor bone marrows used for allogenic bone marrow transplantation in the National Institute of Haematology and Blood Transfusion between January, 1984 and January, 1988. In 10 bone marrow transplanted patients long-term follow up of bone marrow CFU-GM regeneration was carried out. Graft sizes were the following: 2.91 +/- 0.62 X 10(8)/kg body weight nucleated cells and 19.2 +/- 14 X 10(4)/kg body weight (CFU-GM. Preinfusion procedures (centrifugation and resuspension) did not alter CFU-GM content of the grafts. Separation of nucleated cells with hydroxyethylstarch, applied for ABO mismatched donor bone marrow, however, resulted in a 30 per cent loss in CFU-GM. Since higher than threshold graft-sizes for successful engraftment were used, no linear correlation between graft size and speed of granulocyte and platelet recovery was found. Significant difference between regeneration kinetics of bone marrow CFU-GM of patients transplanted for CML or AML and ALL was observed: in AML and ALL patients normal bone marrow CFU-GM level was found 4 to 6 months after transplantation, while in CML patients CFU-GM level approached the lower limit of the normal value only 10 to 14 months after transplantation. Granulocyte and thrombocyte recovery of CML patients showed a significant delay when compared to transplanted AML and ALL patients.