Direct evidence is presented for the clonal nature of the mixed colonies from pluripotent hemopoietic precursors in vitro in adult murine marrow cells. Bone marrow cells from BDF1 mice were fractionated using the technique of velocity sedimentation according to Miller and Phillips to enrich the concentration of the mixed colony-forming units. After 3 h sedimentation, marrow cells in the 15th fraction were harvested and cultured using a methylcellulose culture assay. After 2 days of culture, dividing single cells were individually aspirated and transferred to fresh culture medium for mixed colonies using a Leitz micromanipulator. 92 macrophage-granulocyte colonies, 11 erythropoietic bursts, and 4 mixed colonies were detected in 358 single-cell culture experiments. The present results indicate that mixed colonies are clonal, and the mixed colony-forming units are pluripotent.

中文翻译：

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多能造血前体的体外克隆性质（CFU-mix）。

对于成年小鼠骨髓细胞中来自多能造血前体的混合菌落的克隆性质，提供了直接的证据。根据Miller和Phillips使用速度沉降技术将BDF1小鼠的骨髓细胞分级分离，以富集混合菌落形成单位的浓度。沉降3小时后，收获第15部分中的骨髓细胞，并使用甲基纤维素培养测定法培养。培养2天后，分别吸出分裂的单细胞，并使用Leitz显微操纵器转移至新鲜的培养基中用于混合菌落。在358个单细胞培养实验中检测到92个巨噬细胞-粒细胞集落，11个红细胞爆发和4个混合集落。目前的结果表明混合菌落是克隆的，