Determining force dependence of two-dimensional receptor-ligand binding affinity by centrifugation
Determining force dependence of two-dimensional receptor-ligand binding affinity by centrifugation
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DOI：
10.1016/s0006-3495(98)77807-5
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发表时间：
1998-01-01
影响因子：
3.4
通讯作者：
Zhu, C
中科院分区：
文献类型：
--
作者：
Riper, JW;Swerlick, RA;Zhu, C
受体-配体相互作用的分析对于理解细胞粘附是重要的。测量三维（3D）解离常数（K-d）的传统方法需要溶液中的至少一种分子种类，因此不能直接应用于细胞粘附的情况。我们描述了一种新的方法来测量二维结合特性的受体和配体，附着在表面和其债券受到的力量。该方法利用常见的离心测定来定量粘附。实验的模型已经制定，准确地解决，并仔细测试。该模型是随机的基础上，结合力的结合亲和力。应用该方法检测肿瘤细胞对重组E-选择素的粘附。预测和数据之间的令人满意的协议。E-选择素/碳水化合物配体结合的估计零力2D Kd类似于5 × 10（3）μ m（-2），键相互作用范围为亚埃。我们的研究结果还表明，介导粘附的键的数量很小（
Analyses of receptor-ligand interactions are important to the understanding of cellular adhesion. Traditional methods of measuring the three-dimensional (3D) dissociation constant (K-d) require at least one of the molecular species in solution and hence cannot be directly applied to the case of cell adhesion. We describe a novel method of measuring 2D binding characteristics of receptors and ligands that are attached to surfaces and whose bonds are subjected to forces. The method utilizes a common centrifugation assay to quantify adhesion. A model for the experiment has been formulated, solved exactly, and tested carefully. The model is stochastically based and couples the bond force to the binding affinity. The method was applied to examine tumor cell adherence to recombinant E-selectin. Satisfactory agreement was found between predictions and data. The estimated zero-force 2D K-d for E-selectin/carbohydrate ligand binding was similar to 5 x 10(3) mu m(-2), and the bond interaction range was subangstrom. Our results also suggest that the number of bonds mediating adhesion was small (