Summary:
Background. Amount of CD34+ cells is a critical parameter for quality assessment and successful engraftment of
peripheral blood hematopoietic stem cells (PBSC) during the transplantation of haemopoisis. CD34+ cells are
routinely analysed by immunophenotyping in PBSC and in peripheral blood during mobilization. Other leukocyte
subpopulations are not usually assessed.
Methods and Results. The authors present results of immunophenotyping of subpopulations of CD34+ cells and
leucocytes in samples from donors of PBSC for allogeneic transplantations, who were stimulated with the growth
factor G-CSF at dose 16 µg/kg/day. The amount of CD34+ cells was not significantly different between days 4 and
5; however, there was a significant drop at day 6. CD34+90+ and CD34+61+ subpopulations reached their maximum
at the day 4; partially differentiated CD34+ cells with co-expression of CD33, CD19, and CD7 reached maximum
at the day 6. CD4+ Th-lymphocytes were concentrated in the grafts during leukapheresis, CD4/CD8 ratio in the
grafts was increased to average 3.06.
Conclusions. The knowledge of kinetics of CD34+ subpopulations, together with stem cell selection and ex vivo
manipulation, 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 of
haemopoisis.
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