RESUMEN
The aim of this study was to investigate the effects of human fetal bone marrow stromal cells (FBMSC) in combination with exogenous cytokines on supporting in vitro expansion of CD133(+) cells in cord blood mononuclear cells (MNC). MNCs separated from cord blood (CB) were cultured for up to 14 days in a serum-free system with FBMSC or exogenous cytokines or both of them. On day 0, 6, 10 and 14, total nucleated cells (TNC) were counted; CD133(+) cells were quantified by FACS, and hematopoietic progenitor cells were assessed by semisolid culture assay. The results showed that the number of TNC was remarkably increased in FBMSC and cytokine group, the expansion of CD133(+) cells and CFU were increased in FBMSC and cytokine group except that on day 14. It is concluded that FBMSC play an important role in delaying the differentiation of hematopoietic cells. FBMSC in combination with exogenous cytokines can promote the effective expansion of CB MNC and CD133(+) cells, this expanding system may meet the needs for clinical application of expanded CD133(+) cells.