Epitope and Paratope Mapping of TNFα/Infliximab complex by cross-linking mass spectrometry and integrative modeling reveals high level of interaction specificity

ABSTRACT: Mass spectrometry (MS) has become one of the core technologies to study protein structures, protein-ligand and protein-protein interactions. Chemical cross-linking combined with mass spectrometry (XL-MS) is quickly spreading over different biochemistry laboratories for the continuous increase of its biological applications and standardized protocols that make it attractive for academia and industry research scientists. In recent years, XL-MS has developed as a powerful technique in structural biology, from studying structures of purified proteins in vitro to deciphering intricate protein-protein interaction (PPI) networks in cells, organelles and tissues on a system-wide scale. However, the number of XL-MS studies for the inves-tigation of epitope/paratope mapping of antigen-antibody complexes is still limited up to now. In this manuscript, we devel-oped a simple, fast and automated workflow to define the interaction interface between the chimeric antibody Infliximab (IFX) and its own target, the Tumor Necrosis Factor alpha (TNFα). This workflow integrates XL-MS data to identify areas in proximity to the binding regions and epitope/paratope probability calculation to pinpoint the antigen-antibody binding sites. The data are combined to generate refined 3D models of the antigen-antibody complex which closely resemble the X-ray IFX/TNFα structure and capture their correct interaction surface. The present workflow can be applied to investigate any antigen-antibody complex, even when no previous structural knowledge is available. This strategy is a fascinating oppor-tunity to thoroughly characterize antigen-antibody interactions and to allow the understanding of their binding mechanisms in order to properly design better antibody therapeutics in the future

INSTRUMENT(S): Q Exactive

ORGANISM(S): Escherichia Coli

SUBMITTER: Andrea Di Ianni  

LAB HEAD: Luca Barbero

PROVIDER: PXD043347 | Pride | 2024-02-27

REPOSITORIES: Pride