Rudenko Sergey V
Institute for Problems of Cryobiology and Cryomedicine, National Academy of Sciences of the Ukraine, 61015 Kharkov, Pereyaslavskaya Str. 23, Ukraine.
Biochim Biophys Acta. 2010 Sep;1798(9):1767-78. doi: 10.1016/j.bbamem.2010.05.010. Epub 2010 Jun 8.
Morphological response (MR) of red blood cells represents a triphasic sequence of spontaneously occurring shape transformation between different shape states upon transfer the cells into isotonic sucrose solution in the order: S(0) (initial discoid shape in physiological saline)-->S(1) (echinocytic shape at the beginning of MR, phase 1)-->S(2) (intermediate discoid shape, phase 2)-->S(3) (final stomatocytic shape, phase 3). In this paper, the dynamics of cell shape changes was investigated by non-invasive light fluctuation method and optical microscopy. Among 12 possible transitions between four main shape states, we experimentally demonstrate here an existence of nine transitions between neighbour or remote states in this sequence. Based on these findings and data from the literature, we may conclude that red blood cells are able to change their shape through direct transitions between four main states except transition S(1)-->S(0), which has not been identified yet. Some shape transitions and their temporal sequence are in accord with predictions of bilayer couple concept, whereas others for example transitions between remote states S(3)-->S(1), S(1)-->S(3) and S(3)-->S(0) are difficult to explain based solely on the difference in relative surface areas of both leaflets of membrane suggesting more complex mechanisms involved. Our data show that MR could represents a phenomenon in which the major role can play pH and chloride-sensitive sensor and switching mechanisms coupled with transmembrane signaling thus involving both cytoskeleton and membrane in coordinated shape response on changes in cell ionic environment.
红细胞的形态学反应（MR）呈现出一个三相序列，即当将细胞转移到等渗蔗糖溶液中时，细胞在不同形状状态之间自发发生形状转变，顺序为：S(0)（生理盐水中的初始盘状形状）→S(1)（MR开始时的棘状细胞形状，第1阶段）→S(2)（中间盘状形状，第2阶段）→S(3)（最终口状细胞形状，第3阶段）。在本文中，通过非侵入性光波动法和光学显微镜研究了细胞形状变化的动力学。在四种主要形状状态之间的12种可能转变中，我们在此通过实验证明了该序列中相邻或远程状态之间存在9种转变。基于这些发现和文献数据，我们可以得出结论，红细胞能够通过四种主要状态之间的直接转变来改变其形状，但S(1)→S(0)的转变尚未被识别。一些形状转变及其时间顺序符合双层耦合概念的预测，而其他转变，例如远程状态S(3)→S(1)、S(1)→S(3)和S(3)→S(0)之间的转变，仅基于膜的两个小叶相对表面积的差异难以解释，这表明涉及更复杂的机制。我们的数据表明，MR可能代表一种现象，其中pH和氯离子敏感传感器以及与跨膜信号传导相关的切换机制可能起主要作用，从而使细胞骨架和膜都参与对细胞离子环境变化的协调形状反应。
