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Updated: Jul 17, 2026

Directed Differentiation of Primitive and Definitive Hematopoietic Progenitors from Human Pluripotent Stem Cells
Published on: November 1, 2017
The properties of human fetal bone marrow stromal and hemopoietic cells
The capacity of fetal bone marrow to form stromal cell colonies, granulocyte-macrophage colonies, stromal cell monolayers and to produce granulocyte-macrophage colony stimulating activity from these monolayers was evaluated in comparison to adult bone marrow. Granulocyte-macrophage colony formation on routine feeder layers was approximately equal in both cases. The fetal bone marrow colonies were larger in size than those from adult precursors. There were at least ten times more stromal cell precursors in fetal bone marrow than in adult bone marrow. The fetal bone marrow stromal cell monolayer formed within 7-12 days whereas adult stromal monolayer formation required 3-4 weeks. Fetal bone marrow stromal cell monolayer produced granulocyte-macrophage colony-stimulating activity (GM-CSA) effective only for fetal GM precursors, whereas adult bone marrow produces GM-CSA effective for fetal and adult normal and CML bone marrow.
The capacity of fetal bone marrow to form stromal cell colonies, granulocyte-macrophage colonies, stromal cell monolayers and to produce granulocyte-macrophage colony stimulating activity from these monolayers was evaluated in comparison to adult bone marrow. Granulocyte-macrophage colony formation on routine feeder layers was approximately equal in both cases. The fetal bone marrow colonies were larger in size than those from adult precursors. There were at least ten times more stromal cell precursors in fetal bone marrow than in adult bone marrow. The fetal bone marrow stromal cell monolayer formed within 7-12 days whereas adult stromal monolayer formation required 3-4 weeks. Fetal bone marrow stromal cell monolayer produced granulocyte-macrophage colony-stimulating activity (GM-CSA) effective only for fetal GM precursors, whereas adult bone marrow produces GM-CSA effective for fetal and adult normal and CML bone marrow.
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