Adhesivity and rigidity of erythrocyte membrane in relation to wheat germ agglutinin binding.
Adhesivity and rigidity of erythrocyte membrane in relation to wheat germ agglutinin binding.
复制标题
红细胞膜与小麦胚芽凝集素结合有关的粘附性和刚度。
DOI：
10.1083/jcb.98.4.1201
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发表时间：
1984-04
期刊：
影响因子：
--
通讯作者：
Leung A
中科院分区：
文献类型：
--
作者：
Evans E;Leung A
植物凝集素麦芽凝集素(WGA)与红细胞膜的结合导致红细胞膜僵硬。我们的目标之一是直接测量WGA结合对膜刚性的影响，并将硬化与WGA结合的动力学和水平联系起来。我们的另一个目标是测量WGA结合在一起的红细胞的黏附强度和细胞分离的机制。用微管吸入法测定红细胞膜硬度。进入吸管的吸压-长度数据的斜率提供了膜拉伸模数的测量。收集细胞与WGA溶液在0.01-10微克/毫升浓度范围内的平衡数据。通过微管分离两细胞聚集体来研究红细胞-红细胞的黏附特性。首先，通过吸入从WGA溶液中选择一个“测试”细胞到一个小的微管中，然后转移到一个单独的小室，里面有不含WGA的缓冲液中的红细胞。在这里，用另一个移液管吸入第二个细胞，并操纵到靠近测试细胞表面的位置，产生粘性接触。将松弛池从测试池表面分步骤分离，附着力由吸管压力和池几何形状得出。此外，我们用激光显微荧光系统测量了荧光标记的WGA与单个红细胞的时间依赖性结合和释放。结果表明，红细胞膜的硬化和荧光标记的WGA与膜表面的结合遵循相同的浓度和时间依赖关系。膜僵硬的阈值浓度约为0.1微克/毫升，达到平衡的时间过程接近1小时，最大僵硬(几乎是正常膜弹性模数的30倍)出现在大于2微克/毫升的浓度，达到平衡的时间不到1分钟。WGA结合还将正常的弹性膜行为改变为非弹性的、类塑料的响应，这表明膜的机械拉伸导致表面平面内的交联度增加。与硬化效应相似，我们观察到与WGA溶液平衡的细胞膜的粘附性在浓度大于0.1微克/毫升时显著增加。
Binding of the plant lectin wheat germ agglutinin (WGA) to erythrocyte membranes causes membrane rigidification. One of our objectives has been to directly measure the effects of WGA binding on membrane rigidity and to relate rigidification to the kinetics and levels of WGA binding. Our other objective has been to measure the strength of adhesion and mechanics of cell separation for erythrocytes bound together by WGA. The erythrocyte membrane rigidity was measured on single cells by micropipette aspiration. The slope of the suction pressure-length data for entry into the pipette provided the measure of the membrane extensional modulus. Data were collected for cells equilibrated with WGA solutions in the range of concentrations of 0.01- 10 micrograms/ml. Erythrocyte-erythrocyte adherence properties were studied by micropipette separation of two-cell aggregates. First, a "test" cell was selected from a WGA solution by aspiration into a small micropipette, then transferred to a separate chamber that contained erythrocytes in WGA-free buffer. Here, a second cell was aspirated with another pipette and maneuvered into close proximity of the test cell surface, and adhesive contact was produced. The flaccid cell was separated from the test cell surface in steps at which the force of attachment was derived from the pipette suction pressure and cell geometry. In addition, we measured the time-dependent binding and release of fluorescently labeled WGA to single erythrocytes with a laser microfluorometry system. The results showed that the stiffening of the erythrocyte membrane and binding of fluorescently labeled WGA to the membrane surface followed the same concentration and time dependencies. The threshold concentration for membrane stiffening was at approximately 0.1 microgram/ml where the time course to reach equilibrium was close to 1 h. The maximal stiffening (almost 30-fold over the normal membrane elastic modulus) occurred in concentrations greater than 2 micrograms/ml where the time to reach equilibrium took less than 1 min. The WGA binding also altered the normal elastic membrane behavior into an inelastic, plastic-like response which indicated that mechanical extension of the membrane caused an increase in cross-linking within the surface plane. Similar to the stiffening effect, we observed that the membrane adhesivity of cells equilibrated with WGA solutions greatly increased with concentration greater than 0.1 microgram/ml.(ABSTRACT TRUNCATED AT 400 WORDS)