Deman J J, Bruyneel E A
J Cell Sci. 1977;27:167-81. doi: 10.1242/jcs.27.1.167.
The intercellular adhesiveness of density-inhibited (D.I.) and fast-growing (F.G.) HeLa cells and of trypsin-treated preparations of these, has been measured at temperatures between 37 and 6 degrees C. In EDTA-containing buffer medium, F.G. cells differ from D.I. cells in that only the former display an increase in adhesiveness below 30 degrees C. This increase is prevented by previous treatment with trypsin. The presence of Ca2+ in the buffer medium causes a narrowing of the thermal transition region of intact F.G. cells. On intact D.I. cells Ca2+ causes an increase in adhesiveness at temperatures below 20 degrees C. Previous trypsinization of F.G. cells diminishes the effect of subsequent Ca2+ addition. The adhesiveness of trypsinized D.I. cells is indifferent to changes in temperature in Ca2+-containing buffer medium. The results are considered evidence for the occurrence of a phase transition in the glycoprotein domains of the plasma membrane of fast-growing cells. The transition is influenced by growth rate, trypsinization and Ca2+. The fluidity of the membrane glycoproteins is considered to be higher on density-inhibited cells than on fast-growing cells. No phase transition could be detected after incorporation of the fluorescent compound 1,6-diphenyl 1,3,5-hexatriene into the lipid domain of the plasma membrane. The fluidity of the membrane lipids is lower on density-inhibited cells than on fast-growing cells.
已在37至6摄氏度之间的温度下，对密度抑制（D.I.）和快速生长（F.G.）的海拉细胞以及这些细胞经胰蛋白酶处理后的制剂的细胞间黏附性进行了测量。在含有乙二胺四乙酸（EDTA）的缓冲培养基中，F.G.细胞与D.I.细胞的不同之处在于，只有前者在低于30摄氏度时黏附性会增加。这种增加可通过先前用胰蛋白酶处理来防止。缓冲培养基中钙离子（Ca2+）的存在会使完整的F.G.细胞的热转变区域变窄。在完整的D.I.细胞上，Ca2+在低于20摄氏度时会导致黏附性增加。F.G.细胞先前经胰蛋白酶处理会减弱随后添加Ca2+的效果。经胰蛋白酶处理的D.I.细胞的黏附性在含Ca2+的缓冲培养基中对温度变化不敏感。这些结果被视为快速生长细胞质膜糖蛋白结构域发生相变的证据。该相变受生长速率、胰蛋白酶处理和Ca2+的影响。密度抑制细胞上膜糖蛋白的流动性被认为高于快速生长细胞。在将荧光化合物1,6 - 二苯基 - 1,3,5 - 己三烯掺入质膜的脂质结构域后，未检测到相变。密度抑制细胞上膜脂质的流动性低于快速生长细胞。
