Résumé
The objective of this study was to explore the effect of culture system from embryonic fibroblasts and leukemia inhibitory factor (LIF) on expansion of mouse bone marrow hematopoietic progenitor cells ex vivo, and to observe its effect on the expression of homing-related cell adhesion molecules among VLA-4 (CD49e), VLA-5 (CD49e), LFA-1 (CD11a), HCAM (CD44) and L-selectin (CD62L). The culture system from the mouse embryonic fibroblasts inactivatd by mitomycin C and contained LIF was used to culture with mouse BMMNC for 7 days. The total number of BMMNC, CFC, Sca-1(+) cells, cell apoptosis rate and the expression of above cell adhesion molecules were counted. The results showed that culture system consisted of embryonic fibroblasts and LIF significantly enhanced the total number of BMMNC, CFC, Sca-1(+) cells, suppressed cell apoptosis (P < 0.05). In control without MEF and LIF, the total number of BMMNC was reduced remarkedly, CFC and Sca-1(+) cells were completely dead, the majority of cells produced apoptosis (P < 0.01). The expression of CD49d, Cd44 and CD61L on Sca-1(+) cells were similar to that befor expression (P < 0.05), but the expression of CD49e and CD11a on Sca-1(+) cells were remarkably increased (P < 0.05). It is concluded that culture system from embryonic fibroblasts and LIF can only significantly expand mouse bone marrow hematopoietic progenitor cells ex vivo, but the expanded hematopoietic progenitor may well sustain the expression of homing-related adhesion molecules. The homing functions of these expanded hematopoietic progenitors kept no change.