IS CELL SORTING CAUSED BY DIFFERENCES IN WORK OF INTERCELLULAR-ADHESION - CRITIQUE OF STEINBERG HYPOTHESIS
IS CELL SORTING CAUSED BY DIFFERENCES IN WORK OF INTERCELLULAR-ADHESION - CRITIQUE OF STEINBERG HYPOTHESIS
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DOI：
10.1016/0022-5193(76)90019-9
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发表时间：
1976-01-01
影响因子：
2
通讯作者：
HARRIS, AK
中科院分区：
文献类型：
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作者：
HARRIS, AK
马尔科姆·斯坦伯格提出的差异粘附假说提出，聚集的[动物]细胞的组织型分选行为在机制上等同于液体表面张力的某些方面，特别是不同表面张力的不混溶液体的自发分离。根据斯坦伯格的假设，聚集细胞之间的粘附力在细胞分选中所起的作用基本上与液体表面张力中分子间吸引力所起的作用相同。讨论了分子间吸引力（在液体中）和细胞间粘附（在聚集体中）之间的许多关键区别。液滴在热力学上是封闭的系统，而活细胞的聚集体可以产生不确定量的代谢能量，能够改变细胞位置和粘附。细胞间粘附不仅仅是近距离的吸引力，因为除了最初将细胞拉在一起的力之外，细胞还可以通过其他力保持在一起。细胞间粘附的破坏不一定是这些粘附形成的热力学逆转。因为细胞间粘附通常集中在相对较小的焦点，例如桥粒，所以细胞间粘附的最大化不一定需要细胞间接触面积的最大化，反之亦然。提出了几个额外的替代假设，每个假设在理论上都能够解释细胞分选和细胞聚集行为的其他类似表面张力的方面，斯坦伯格将其解释为差异粘附的结果。提出了差异表面收缩假说，其中细胞分选和相关现象是在暴露于周围培养基的细胞表面部分上诱导发生细胞表面收缩的结果。由于有证据表明胚胎上皮的各种内陷型运动是由细胞表面收缩引起的，差异表面收缩是组织型细胞分选最可能的解释。建议进行许多实验来检验这些不同的假设。
The differential adhesion hypothesis, developed by Malcolm Steinberg, proposes that the histotypic sorting out behavior of aggregated [animal] cells is mechanistically equivalent to certain aspects of liquid surface tension, specifically the spontaneous separation of immiscible liquids of differing surface tension. According to Steinberg''s hypothesis, the adhesive forces between aggregated cells play essentially the same role in cell sorting as are played by intermolecular attractive forces in liquid surface tension. A number of crucial distinctions between intermolecular attraction (in liquids) and intercellular adhesion (in aggregates) are discussed. Liquid drops are closed systems thermodynamically whereas aggregates of living cells can generate an indeterminate amount of metabolic energy capable of altering cell positions and adhesions. Intercellular adhesions are more than just close range attractions since cells can be held together by forces in addition to those which originally pulled them together. The breakage of intercellular adhesions need not be simply the thermodynamic reverse of the formation of those adhesions. Because intercellular adhesion is generally concentrated at relatively small foci such as desmosomes, a maximization of intercellular adhesion does not necessarily require a maximization of intercellular contact area, or vice versa. Several additional, alternative hypotheses are proposed, each of which is theoretically capable of explaining cell sorting and the other surface tension-like aspects of cell aggregate behavior which Steinberg explains as consequences of differential adhesion. A differential surface contraction hypothesis is proposed, in which cell sorting and related phenomena are the results of cell surface contractions induced to occur over those portions of the cell surface which are exposed to the surrounding culture medium. Because of the evidence that various invagination type movements of embryonic epithelia are caused by cell surface contractions, differential surface contraction is the most likely explanation of histotypic cell sorting. A number of experiments are suggested by which these various hypotheses might be tested.