The patterns on chondrogenesis of cells from facial primordia of chick embryos in micromass culture.
The patterns on chondrogenesis of cells from facial primordia of chick embryos in micromass culture.
复制标题
微团培养中鸡胚面部原基细胞的软骨形成模式。
作者：
S. Wedden;M. Lewin;C. Tickle
在微块（高密度）培养中研究了24期鸡胚胎前鼻块、下颌骨和上颌骨间充质细胞的软骨形成。在软骨分化的数量和模式上有明显的差异。在额鼻肿块细胞的培养中，形成一层中央软骨；在培养的下颌骨细胞中，软骨分化较少，形成结节；而在上颌骨细胞的培养中，几乎没有发生软骨形成。在20期胚胎的培养物中也发现了相同的软骨形态。28期，额鼻肿块培养形成软骨结节，下颌骨培养中结节的数量明显减少。在微群体培养中，来自面部和肢体芽的细胞的软骨形成模式有惊人的相似之处。20期和-24期鸡胚的额鼻团细胞培养物类似于从肢芽发育区建立的细胞。进展区是肢体未分化的区域，位置信号在其中起作用。从28期鸡胚胎的额鼻块和所有阶段的下颌骨建立的培养物类似于整个肢体芽的培养物。这些包含已提交和未提交的混合单元。面部原基外胚层在微团培养中局部抑制软骨形成，这可能提供位置线索。面部原基细胞成软骨潜能的差异可能是对额鼻肿块的特异性类视黄醇作用的基础。
Chondrogenesis of mesenchymal cells from the frontonasal mass, mandibles and maxillae of stage-24 chick embryos has been investigated in micromass (high-density) cultures. Distinct differences in the amount and pattern of cartilage differentiation are found. In cultures of frontonasal mass cells, a central sheet of cartilage develops; in cultures of mandible cells, less cartilage differentiates and nodules form; while in cultures of maxillae cells, virtually no chondrogenesis takes place. The same patterns of cartilage are found in cultures established from stage-20 embryos. At stage 28, frontonasal mass cultures form cartilage nodules and the number of nodules in mandible cultures is markedly decreased. There are striking parallels between the chondrogenic patterns of cells from the face and limb buds in micromass culture. The frontonasal mass cell cultures of stage-20 and -24 chick embryos resemble those established from the progress zone of limb buds. The progress zone is an undifferentiated region of the limb in which positional cues operate. Cultures established from the frontonasal mass of stage-28 chick embryos and from the mandibles of all stages resemble cultures of whole limb buds. These contain a mixture of committed and uncommitted cells. Ectoderm from facial primordia locally inhibits chondrogenesis in micromass cultures and this could provide a positional cue. The differences in chondrogenic potential of cells from facial primordia may underlie the specific retinoid effects on the frontonasal mass.