Age-dependent changes in myogenic precursor cell compartment sizes. Evidence for the existence of a stem cell.
Age-dependent changes in myogenic precursor cell compartment sizes. Evidence for the existence of a stem cell.
复制标题
肌源性前体细胞区室大小的年龄依赖性变化。
DOI：
10.1016/0014-4827(84)90668-2
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发表时间：
1984
影响因子：
3.7
通讯作者：
Holtzer,H
中科院分区：
文献类型：
--
作者：
Quinn,LS;Nameroff,M;Holtzer,H
从胚胎发育第8~14天的鸡胚胎胸肌分离出单个肌源性细胞。当单独克隆时，这些细胞在培养中产生了三种类型的集落：(1)阳性：所有克隆中的细胞都是终末分化的肌肉细胞；(2)阴性：克隆中没有细胞是终末分化的肌肉；(3)混合：克隆中的部分细胞是终末分化的肌肉细胞。各年龄段阳性克隆均含有2n个细胞(n=0、1、2、3、4)。在所有大小的克隆中都发现了阴性克隆，并且没有聚集在细胞数量的2的幂周围。到目前为止，在细胞数超过24个的克隆中，混合克隆是最常见的类型。对胚胎肌肉组织中细胞数量的估计表明，虽然所有肌源性隔室中的细胞数量随着胚胎年龄的增长而稳步增加，但产生大型混合克隆的前体细胞的数量和比例显著增加。从相当于大型混合克隆的细胞群体制备的亚克隆，既产生了小的阳性克隆，也产生了大的混合克隆。这表明大的混合克隆的前体也是较小的阳性克隆的前体。这些观察结果提出了一种肌源性谱系的模型，在这种模型中，存在一种干细胞，可以通过一系列不对称的分裂产生终末分化的肌肉细胞队列。该模型可以解释在体外和体内产生终末分化肌肉细胞的不同步现象。
Individual myogenic cells were isolated from the pectoralis muscles of chick embryos from days 8–14 of embryogenesis. When separately cloned, these cells produced three types of colonies in culture: (1) Positive: all cells in the clone were terminally differentiated muscle cells; (2) negative: no cells in the clone were terminally differentiated muscle; (3) mixed: some cells in the clone were terminally differentiated muscle. Positive clones from all ages tended to contain 2ncells (n= 0, 1, 2, 3, 4). Negative clones were found in all sizes and did not cluster around powers of 2 in cell number. Mixed clones were, by far, the most common type among those clones larger than 24in cell number. Estimates of cell numbers in embryonic muscle tissue revealed that, while the numbers of cells in all myogenic compartments increased steadily with embryonic age, the number and percentage of precursor cells that produced large mixed clones increased dramatically. Subclones, prepared from populations of cells equivalent to large mixed clones, yielded both small positive and large mixed colonies. This indicated that the precursors to the large mixed clones were also precursors to the smaller positive clones. These observations suggest a model for the myogenic lineage in which there exists a stem cell that can generate, by a series of asymmetric divisions, cohorts of terminally differentiated muscle cells. The model can explain the asynchrony of production of terminally differentiated muscle cells both in vitro and in vivo.