The Correlation between CD34+ Cell and Nucleated RBC Counts in Human Cord Blood

ABSTRACT

PURPOSE: Human umbilical cord blood as a potential source of hematopoietic stem cell for stem cell transplantation in children has recently been advocated. Clinical application of cord blood transplantation, however, requires adequate blood volume and number of stem cells. Currently, the number of stem cells in the cord blood is usually measured by flowcytometry, which requires strict quality control and high costs. Here, we postulate that the number of nucleated red blood cells(NRBC) which are relatively immature erythroid cells may correlate well with that of CD34-expressing(CD34+) cells which are considered lymphohematopoietic precursors. If so, CD34+ cell-rich cord blood can be selected and such cells enumerated by a simple and cost-effective blood smears. METHODS: Correlation between CD34+ cell and nucleated RBC in human cord blood were checked. Sixty cord blood specimens(30 specimens for group A with NRBC>500/mul and 30 specimens for group B with NRBC500/ul; 55+/-61(SD))(p<0.005). 3.Regression relationship among CD34+ cell, WBC, and NRBC counts was as following. ln(CD34+ cell) = -12.21 + 1.46xln(WBC)+ 0.25xln(NRBC) gamma2=30.07 p=0.0001 4.There was a significant correlation between CD34+ cell counts and NRBC counts(gamma=0.4334, p<0.005) CONCLUSIONS: Our results suggest that there is a significant correlation between CD34+ cell counts and NRBC counts, and that CD34+ cell-rich cord blood specimens can be selected by a simple NRBC counting.