Plerixafor vs G-CSF: Graft Stem Cells Composition in HSCT with αβ T depletion in Pediatric Cohort

Introduction: Hematopoietic stem cells (SC) are a heterogeneous population including the early-uncommitted fraction as well as different committed subsets.Donor mobilization strategy seems to be a significant factor affecting SC composition and engraftment kinetics.The aim of this study was to investigate the impact of different mobilization protocols: G-CSF (GCSF) or G-CSF with Plerixafor in case of inadequate stimulation with G-CSF alone (Plerixafor) on SC composition in a large cohort of pediatric patients transplanted from allo-compatible donors with T cells depletion. Methodology: Specimens from 161 grafts -31 Plerixafor (19.3%) and 130 GCSF (80.7%) were under investigation.The samples were immunophenotyped by flow cytometry: pluripotent hematopoietic stem cells (HSC) -CD45RA-CD34+CD90+, multipotent progenitor (MPP) -CD45RA-CD34+CD90-CD133+, lymphoid-primed multipotent progenitor -(LMPP) -CD45RA+CD133+CD34+CD38lowCD10-, late granulocytes and macrophages progenitor -(late GMP) -CD45RA+CD133+CD34+CD38+CD10-, multi-lymphoid progenitor -(MLP) -CD45RA+CD133+CD34+CD38+CD10+, B-lymphoid progenitor -(BLP) -CD45RA+CD133-CD34+CD38++CD10+CD19+ and erythro-myeloid progenitor -(EMP) -CD45RA-CD34+CD133-CD10-CD38+ (J Dmytrus et.Al. 2016).Differences were assessed using Mann-Whitney test.The engraftment was assessed using the data of leukocytes (WBC) and thrombocytes (PLT) engraftment (days WBC 1*106/ml, PLT 20*10^6/ml).