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bioRxiv · 10.1101/2020.11.03.366476

Binding site localization on non-homogeneous cell surfaces using topological image averaging

Kumra Ahnlide, V.·Kumra Ahnlide, J.·Beech, J. P.·Nordenfelt, P.
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Abstract

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. In the present work, we have developed a method for imaging-based localization of binding sites on cellular surface proteins. The cellular morphology typically varies, and antibodies often bind in a non-homogenous manner, making traditional particle-averaging strategies challenging for accurate native antibody localization. Nanometer-scale resolution is achieved through localization in one dimension, namely the distance from a bound ligand to a reference surface, by using topological image averaging. Our results show that this method is well suited for antibody binding site measurements on native cell surface morphology.

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Kumra Ahnlide, V., Kumra Ahnlide, J., Beech, J. P., Nordenfelt, P.. 2020-11-04. Binding site localization on non-homogeneous cell surfaces using topological image averaging. https://doi.org/10.1101/2020.11.03.366476

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