Division of Infection Medicine, Department of Clinical Sciences, Faculty of Medicine, Lund University, Lund, Sweden.
Division of Solid State Physics, Department of Physics, Lund University, Lund, Sweden.
Elife. 2022 Feb 24;11:e64709. doi: 10.7554/eLife.64709.
Antibody binding to cell surface proteins plays a crucial role in immunity, and the location of an epitope can altogether determine the immunological outcome of a host-target interaction. Techniques available today for epitope identification are costly, time-consuming, and unsuited for high-throughput analysis. Fast and efficient screening of epitope location can be useful for the development of therapeutic monoclonal antibodies and vaccines. Cellular morphology typically varies, and antibodies often bind heterogeneously across a cell surface, making traditional particle-averaging strategies challenging for accurate native antibody localization. In the present work, we have developed a method, SiteLoc, for imaging-based molecular localization on cellular surface proteins. Nanometer-scale resolution is achieved through localization in one dimension, namely, the distance from a bound ligand to a reference surface. This is done by using topological image averaging. Our results show that this method is well suited for antibody binding site measurements on native cell surface morphology and that it can be applied to other molecular distance estimations as well.
抗体与细胞表面蛋白的结合在免疫中起着至关重要的作用，表位的位置完全可以决定宿主-靶标相互作用的免疫结果。目前可用于表位鉴定的技术既昂贵又耗时，不适合高通量分析。快速有效地筛选表位位置可用于治疗性单克隆抗体和疫苗的开发。细胞形态通常不同，抗体通常在细胞表面不均匀结合，这使得传统的粒子平均策略难以实现对天然抗体定位的准确分析。在本工作中，我们开发了一种基于成像的细胞表面蛋白分子定位方法 SiteLoc。通过在一个维度上进行定位，即从结合配体到参考表面的距离，实现了纳米级分辨率。这是通过拓扑图像平均来实现的。我们的结果表明，该方法非常适合于对天然细胞表面形态上的抗体结合位点进行测量，并且也可应用于其他分子距离估计。
