Abstract
We studied the concentration of hemopoietic progenitor cells (BFU-E, CFU-GM, CFU-mix) in the blood, comparing group of 42 neonates of various gestational ages, 26 infants and 10 adults ; and studied proliferative potential of cord blood and childhood bone marrow in vitro. Hemopoietic progenitor cells were assayed by methylcellulose culture containing IL-3, G-CSF and erythropoietin, and concentration of the progenitors were expressed as number of colonies per 1 ml of blood. Blood samples were obtained from neonates or umbilical cords of various gestational ages (from 26 to 41 weeks). The correlation between gestational ages and the concentration of progenitor cells were calculated by means of regression linear analysis. This study showed that as the neonate becomes more premature, the number of progenitor cells increases in a stepwise fashion ; regression linear coefficients of BFU-E, CFU-GM and CFU-mix were 0.739, 0.695, and 0.718, respectively. There was close relationship between gestational ages of neonates and concentration of circulating hemopoietic stem cells. Proliferative potential of progenitor cells of newborns increased to about 5 times compared with those of childhood bone marrow cells. Relation between abnormal number or abnormal proliferative potentials of cord blood stem cells and various congenital hematopoietic disorders will be studied in the future.
