Berger W K, Uhrík B
I, Physiologisches Institut, Universität des Saarlandes, Homburg, Germany.
Experientia. 1996 Sep 15;52(9):843-50. doi: 10.1007/BF01938868.
The formation of intracellular ice (IIF), usually a lethal event to be avoided when cryopreserving cells, should, however, be enforced during the cryosurgical destruction of tumour cells. IIF has been investigated so far only in single cells in suspension. Because cells in tissues cannot be successfully cryopreserved, in contrast to single cells in suspension, the mechanism of IIF in tissues may depend on factors that facilitate IIF. We studied IIF in cell strands from salivary glands, which represent a simple form of a tissue. Their cells are connected by channels responsible for intercellular communication. A substantial fraction of cell dehydration during freezing occurs before cells are encapsulated by ice, and the degree of this pre-ice-front shrinkage appears to influence IIF. In strands with coupled cells IIF spread from one cell to adjacent cells in a sequential manner with short delays (200-300 ms), suggesting cell-to-cell propagation via intercellular channels. In strands pretreated with decoupling agents (dinitrophenol, heptanol), sequential IIF was absent. Instead, formation of ice was random, with longer and variable delays between consecutive darkenings indicating IIF. Results suggest that the mechanism of IIF spread, and consequently the degree of cryodamage in tissue, can be influenced by the presence of intercellular channels (gap junctions).
细胞内结冰（IIF）通常是细胞冷冻保存时应避免的致死事件，然而，在肿瘤细胞的冷冻手术破坏过程中却应促使其发生。到目前为止，对IIF的研究仅在悬浮的单细胞中进行。与悬浮的单细胞不同，由于组织中的细胞无法成功冷冻保存，因此组织中IIF的机制可能取决于促进IIF的因素。我们研究了唾液腺细胞链中的IIF，唾液腺细胞链代表了一种简单的组织形式。它们的细胞通过负责细胞间通讯的通道相连。在细胞被冰包裹之前，冷冻过程中细胞脱水的很大一部分就已发生，而这种冰前沿前收缩的程度似乎会影响IIF。在细胞相连的细胞链中，IIF以短延迟（200 - 300毫秒）依次从一个细胞扩散到相邻细胞，这表明是通过细胞间通道进行细胞间传播。在用去偶联剂（二硝基苯酚、庚醇）预处理的细胞链中，不存在依次发生的IIF。相反，结冰是随机的，连续变暗之间的延迟更长且变化不定，这表明存在IIF。结果表明，IIF扩散的机制以及组织中冷冻损伤的程度可能会受到细胞间通道（间隙连接）的影响。
