[Effect of recombinant human FLT3 ligand (rhFL) on in vitro expansion of human cord blood CD34+ cells].

OBJECTIVE

To determine the effects of recombinant human FLT3 ligand (rhFL) on in vitro expansion of human cord blood CD34+ cells.

METHODS

Human cord blood CD34+ cells were enriched by using a magnetic cell isolation system. CD34+ cells were incubated in liquid culture in the presence of different cytokines. The total number of all cells and the number of CD34+ cells and hematopoietic progenitor cells (CFU-GM and BFU-E) were counted at various time intervals.

RESULTS

Human cord blood CD34+ cells could be enriched to the purity of more than 80%. The number of CD34+ cells increased 3.4 folds in the presence of rhFL + IL3 + IL6 + GMCSF + EPO in seven days, while in the control group without rhFL, it increased 1.5 folds. The difference of the number of more matured hematopoietic progenitor cells in the CD34+ cell population between the control group and the rhFL group was not significant.

CONCLUSION

Only the primitive hematopoietic progenitor cells are expanded by rhFL according to the results obtained in the exclusion method.