ABSTRACT
BACKGROUDS: Different clinical outcomes of umbilical cord blood (CB) transplantation and GM-CSF mobilized peripheral blood stem cell (LB) transplantation stimulated our interests in immune characteristics of various stem cell sources so that we investigated immunophenotypes of mononuclear cells of twenty-six CB and ten LB cases and twenty normal adult peripheral blood (AB). METHODS: Two-color direct immunofluorescence analysis was performed using FACScan (Becton-Dickinson, USA) and monoclonal antibodies were CD34FITC/CD33PE, CD34FITC/CD45ROPE, CD34PE/CD45RAFITC, CD34PE/CD38FITC, CD4PE/CD45RAFITC, CD4FITC/CD45ROPE, CD8PE/CD45RAFITC, CD8PE/CD11bFITC, CD8PE/CD57FITC, CD8FITC/CD38PE (Serotec), and Simulset IMK lymphocyte kit (Becton-Dickinson). RESULTS: CD34+ cell frequencies of CB and LB were four times higher than that of AB. CD34+CD38- cell frequency was higher in CB, 41.5+/-28.1% compared to 20.1+/-15.8% in LB (P=0.0391) and frequencies of CD34+CD33+, CD34+CD45RA-, and CD34+CD45RO+ showed no difference. LB showed higher frequency of CD3+ and CD8+ cells and lower frequency of CD4+ and CD19+ cells compared to that of CB and AB. CD4+CD45RA+ na ve cell frequency was higher in CB (29.3%) compared to 2.3% of LB. CD4+CD45RO+ memory T lymphocyte frequency (8.5%) and CD8+CD57+ cell frequency (1.0%) were lowest in CB. CD8+CD45RA+ and CD8+CD11+ cell frequencies showed no difference. No statistically significant differences in CD34+ cell and its subsets and lymphocytes and their subsets were observed between normal vaginal delivered umbilical cord blood (VD) and Cesarean sectioned umbilical cord blood (CS), except CD8+CD11+ cell frequency was higher in VD (11+/-7.6%) compared to that (4.0+/-2.3%) in CS (P=0.0081). CONCLUSIONS: CB showed higher frequency of immature hematopoietic stem cell precursors and na ve lymphocytes compared to that of LB and AB and LB showed higher frequency of T lymphocytes and lower frequency of B lymphocytes compared to those of CB and AB, which might be the possible causes of the different clinical outcome. Study on the standard immunophenotypic values in various hematopoietic stem cell products using sufficient number of subjects is necessary for the guideline of clinical utilization.