Phenotypic changes in neutrophil granulocytes of healthy donors after G-CSF administration

Abstract

BACKGROUND AND OBJECTIVE: The aim of the present work was to analyze the immunophenotypic changes in neutrophil granulocytes (NG) and their evolution over time in 16 healthy donors who received G-CSF for stem cell mobilization for allogeneic peripheral blood stem cells (PBSC) transplantation. DESIGN AND METHODS: The mobilization schedule consisted of G-CSF (Filgrastimq, Amgen) 10 microg/kg, s.c. for five consecutive days. Apheresis began 16-24h after the last dose of G-CSF. Immunophenotypic analysis (CD10, CD14, CD15, CD16, CD71, CD34 and HLA-DR) of NG and measurement of G-CSF serum levels were performed before G-CSF administration (day 0), on the fifth day of G-CSF treatment and days +7 and +30 after the last dose of G-CSF. RESULTS: After G-CSF administration, peripheral blood NG presented increased expression of HLA-DR, CD34, CD14, and CD71, in addition to decreased expression of CD10 and CD15 and CD16 fluorescence mean intensity. The phenotypic changes on NG were parallel to serum G-CSF levels. All the phenotypic changes returned to the baseline values by one month after the end of G-CSF treatment. No changes were found in the expression of HLA-DR on T and B-lymphocytes. INTERPRETATION AND CONCLUSIONS: These immunophenotypic changes suggest that after G-CSF administration NG from healthy donors who received G-CSF for stem cell mobilization carry transient features of immature phenotype and have increased functional activity.