Highly fluorescent reticulocytes after CD34⁺ peripheral blood progenitor cell transplantation

Abstract

Highly fluorescent reticulocyte (HFR) counts were evaluated in 13 consecutive patients affected by hematological malignancies and submitted to autologous selected CD34⁺ peripheral blood progenitor cell (PBPC) transplantation. Results were compared with a historical group of patients comparable for age, disease and conditioning regimen submitted to unfractionated PBPC transplantation. HFR counts of the CD34⁺ group declined to an undetectable level from day +4 to day +10 when they became detectable and reached 5% of total reticulocyte count by day +12. In the historical group, the nadir was identical but the recovery was faster (day +9). Total reticulocyte count >1% was achieved at days +17 and +11, respectively. The absolute neutrophil count (ANC) recovery was identical in both groups, achieving a value >0.5 × 10⁹/l at day +13 after reinfusion. Hence, in the historical group, HFR count gave advance notice of complete and stable hemopoietic engraftment while in the CD34⁺ group HFR and ANC count showed almost simultaneous recovery.