Limeback H, Otsuka K, Yao K L, Aubin J E, Sodek J
Can J Biochem Cell Biol. 1984 Jun;62(6):462-9. doi: 10.1139/o84-063.
A number of bone cell clones isolated from rat calvaria have been maintained in culture for more than 3 years. Several of these clones have undergone dramatic changes in phenotype. One of these clones, RCB 2.2, was observed originally to have a fibroblastic morphology in culture and to respond to parathyroid hormone (PTH), but not prostaglandin E2 (PGE2), with an increase in intracellular cAMP. Throughout several passages in early subcultures, these cells synthesized mostly type I collagen, with small amounts of type III and type V collagens. Whereas PTH had no detectable effect on collagen synthesis, PGE2 decreased the amount of total cell layer collagen, with the greatest effect on type III collagen, while increasing the proportion of type V collagen. Subsequent studies on these cells during 3 years in culture have indicated changes in their phenotype including a progressive change in morphology to a more cuboidal shape and a change in collagen synthesis, the cells producing large amounts of the "embryonic" collagen, alpha 1(I) trimer. The reason(s) for the change in collagen expression is unknown, but may be the result of a change in which gene(s) is being expressed.
从大鼠颅骨分离出的许多骨细胞克隆已在培养中维持了3年多。其中一些克隆的表型发生了显著变化。这些克隆之一，RCB 2.2，最初在培养中具有成纤维细胞形态，对甲状旁腺激素（PTH）有反应，但对前列腺素E2（PGE2）无反应，细胞内cAMP增加。在早期传代培养的几个传代过程中，这些细胞主要合成I型胶原蛋白，少量合成III型和V型胶原蛋白。虽然PTH对胶原蛋白合成没有可检测到的影响，但PGE2减少了总细胞层胶原蛋白的量，对III型胶原蛋白的影响最大，同时增加了V型胶原蛋白的比例。在培养3年期间对这些细胞的后续研究表明它们的表型发生了变化，包括形态逐渐变为更立方形，以及胶原蛋白合成的变化，这些细胞产生大量的“胚胎”胶原蛋白α1（I）三聚体。胶原蛋白表达变化的原因尚不清楚，但可能是正在表达哪些基因发生变化的结果。
