1.Enforced Expression of BMI-1 in Postnatal Human CD34+ Cells Promotes Erythroid Differentiation.
Gabsang LEE ; Byung Soo KIM ; Jae Hung SHIEH ; Malcolm A S MOORE
Korean Journal of Hematology 2007;42(3):241-249
BACKGROUND: The Polycomb-group gene Bmi-1 is known to be a molecular regulator of self-renewal of normal and leukemic stem cells and be involved in various aspects of cellular proliferation, differentiation, and survival. METHODS: This study evaluated the effects of overexpression of Bmi-1 on human cord blood CD34+ cells. Bmi-1 was introduced into CD34+ cells through lentivirus transduction. Bmi-1 expressing CD34+ cells were applied to colony forming assay, stromal co-culture, and cytokine-stimulatied culture. RESULTS: Ectopic expression of Bmi-1 resulted in the increased number of erythroid colonies in primary and secondary colony forming assay in an erythropoietin dependent manner. In stromal co-culture, Bmi-1-expressing postnatal hematopoietic stem cells seemed to lose the ability of self-renewal, as determined by week 5 cobblestone area-forming cell assay and by week 5 secondary colony assay. In cytokine-stimulated suspension culture of Bmi-1-transduced CD34+ cells, we observed increased erythropoiesis marked by Glycophorin A expression. CONCLUSION: Our data suggest that ectopic expression of Bmi-1 in human hematopoietic stem/progenitor cells may result in the differentiation to the erythroid lineage rather than promoting self-renewal.
Cell Proliferation
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Coculture Techniques
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Erythropoiesis
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Erythropoietin
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Fetal Blood
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Glycophorin
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Hematopoietic Stem Cells
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Humans*
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Lentivirus
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Stem Cells