The number of particular hematopoietic progenitors cells and the haematopoietic recovery following allo PBSCT.

AlloPBSC-T is rapidly replacing bone marrow transplantation. The minimum nu mber of progenitor cells required for rapid engraftment following PBSCT is unknown, 12 patients underwent alloPBSC-T during treatment for haematologic al malignancy. PBSC's were mobilised with Filgrastim (10 mu g/kg/day sc). T he mobilisation was monitored daily by the number of mononuclear cells (MNC ) and CD34+ cells in peripheral blood. Collections were normally performed on days 4 and 5, by means of apheresis (Fenwall CS 3000+), No futher manipu lation of PBSC was performed. A median of 10.15x 10(8)/kg MNC (range 5.87-1 2.24), 9.075x10(6)/kg CD34+ (range 0.78-18.98), 53.85x10(4)/kg CFU-G (range 17.2-138.4), 28.05x10(4)/kg CFU-M (range 4.1-102.2), 115.65x10(4)/kg BFU-E (range 9.1-255.2), 3.65x10(4)/kg CFU-GEMM (range 0.3-10.4) were infused in to recipients following BuCy120 conditioning, Haematopoietic reconstitution was observed in 11 patients, The median number of days to achieve a neutro phil count of 0.5x10(9)/l was 16 (range 12-20), the platelet count of 20x10 (9)/l was 12 (range 8-20) and RBC transfusion independence was Il(range 8-2 0), 9 recipients developed acute GVHD (3 grade I-0,2 grade II0, 1 grade III 0,3 grade IV0). We found that the number of MNC in PBSC had no influence on the number of progenitors. All the patients who received G-CFU>20x10(4)/kg , BFU-E>60x10(4)/kg and CFU-GEMM>1x10(4)/kg experienced a rapid haematopoie tic recovery. No relation was found between the number of reinfused progeni tors and the appearance of GVHD.