Phenotype and Kinetics Analysis of the CD34+ Cell Subpopulations andLymphocytes of Donors of the Peripheral Haematopoietic Stem Cells for the Allogeneic Transplantation

Overview

Background.
Amount of CD34+ cells is a critical parameter for quality assessment and successful engraftment ofperipheral blood hematopoietic stem cells (PBSC) during the transplantation of haemopoisis. CD34+ cells areroutinely analysed by immunophenotyping in PBSC and in peripheral blood during mobilization. Other leukocytesubpopulations are not usually assessed.Methods and Results. The authors present results of immunophenotyping of subpopulations of CD34+ cells andleucocytes in samples from donors of PBSC for allogeneic transplantations, who were stimulated with the growthfactor G-CSF at dose 16 µg/kg/day. The amount of CD34+ cells was not significantly different between days 4 and5; however, there was a significant drop at day 6. CD34+90+ and CD34+61+ subpopulations reached their maximumat the day 4; partially differentiated CD34+ cells with co-expression of CD33, CD19, and CD7 reached maximumat the day 6. CD4+ Th-lymphocytes were concentrated in the grafts during leukapheresis, CD4/CD8 ratio in thegrafts was increased to average 3.06.Conclusions. The knowledge of kinetics of CD34+ subpopulations, together with stem cell selection and ex vivomanipulation, may have an impact on the speed of engraftment or GvHD prevention in transplanted patients.

Key words:
haematopoietic stem cells, immunophenotyping, CD34+ subpopulation, transplantat ion ofhaemopoisis.