Kaplowitz P B, Moscona A A
Cell Differ. 1976 Jul;5(2):109-19. doi: 10.1016/0045-6039(76)90004-x.
Ouabain and concanavalin A, agents which bind to specific sites in the cell membrane, stimulate DNA synthesis and cell replication in monolayer cultures of neural retina cells from late chick embryos. The results suggest a relationship between control of retina cell replication and properties of the cell membrane. The experiments involved measurements of 3H-thymidine incorporation in primary monolayer cultures (24-48h) of retina cells from embryos of different ages. Stimulation by ouabain was greatest in cells from 14-day embryos, and its magnitude was similar to that elicited in these cell cultures by concanavalin A. Simultaneous treatment of 14-day retina cells with both agents resulted in a greater than additive stimulation of DNA synthesis. Our results demonstrated that, although during normal embryogenesis cell replication in the neural retina has virtually ceased by day 14 of development, some cells retained a capacity for mitogenesis when exposed to conditions such as provided in these experiments. By autoradiography the responding cells were identified as large epithelioid retina cells (LER cells). Under optimal conditions of simultaneous treatment with ouabain and Con A about 20% of the LER cells showed stimulation of DNA synthesis. The nature of LER cells and other aspects of our findings are discussed.
哇巴因和伴刀豆球蛋白A能与细胞膜上的特定位点结合，它们可刺激来自晚期鸡胚的神经视网膜细胞单层培养物中的DNA合成和细胞复制。这些结果表明视网膜细胞复制的控制与细胞膜特性之间存在关联。实验涉及对不同年龄胚胎的视网膜细胞原代单层培养物（24 - 48小时）中3H - 胸苷掺入量的测量。哇巴因对来自14天胚胎的细胞刺激作用最大，其刺激程度与伴刀豆球蛋白A在这些细胞培养物中引起的刺激程度相似。用这两种试剂同时处理14天的视网膜细胞，导致对DNA合成的刺激作用大于两者相加的效果。我们的结果表明，尽管在正常胚胎发育过程中，神经视网膜中的细胞复制在发育到第14天时实际上已经停止，但当暴露于这些实验所提供的条件时，一些细胞仍保留有有丝分裂的能力。通过放射自显影，应答细胞被鉴定为大型上皮样视网膜细胞（LER细胞）。在哇巴因和伴刀豆球蛋白A同时处理的最佳条件下，约20%的LER细胞显示出DNA合成受到刺激。本文讨论了LER细胞的性质以及我们研究结果的其他方面。
