[In vitro expansion of cord blood mononuclear cells supported by fetal bone marrow stromal cells and cytokines].

This study was aimed to explore the role of human fetal bone marrow stromal cells (FBMSC) in combination with exogenous cytokines in supporting the in vitro expansion of cord blood mononuclear cells and the expression of CXCR4(+) and CD49d(+) in CD34(+) cells. Mononuclear cells (MNC) separated from cord blood (CB) were cultured in a serum-free support culture system with FBMSC or exogenous cytokines or both of them. On day 0, 6, 10 and 14, total cells were counted, CD34(+), CD34(+)CXCR4(+) and CD34(+)CD49d(+) cells were quantitated by FACS, and hematopoietic progenitor cells were assessed by semisolid culture assay. The results showed that after culturing for 14 days, CD34(+) cells, CD34(+)CXCR4(+) cells, CD34(+) CD49d(+) cells and colony forming unit (CFU) were significantly increased (P < 0.05). Compared with other groups, expansion multiple of CD34(+), CD34(+)CXCR4(+), CD34(+)CD49d(+) cells and CFU were higher than that in FBMSC and cytokine group (P < 0.05). It is concluded that the culture system used in this study can not only support the expansion of CB MNCs but also increase the number of hematopoietic stem and progenitor cells which has chemokine and adhesion capacity. This culture system may be a feasible way for in vitro culture of cord blood cells.