Self-Induced Back-Action Actuated Nanopore Electrophoresis (SANE) Sensor for Label-Free Detection of Cancer Immunotherapy-Relevant Antibody-Ligand Interactions

Methods Mol Biol. 2022:2394:343-376. doi: 10.1007/978-1-0716-1811-0_20.

Abstract

We fabricated a novel single molecule nanosensor by integrating a solid-state nanopore and a double nanohole nanoaperture. The nanosensor employs Self-Induced Back-Action (SIBA) for optical trapping and enables SIBA-Actuated Nanopore Electrophoresis (SANE) for concurrent acquisition of bimodal optical and electrical signatures of molecular interactions. This work describes how to fabricate and use the SANE sensor to quantify antibody-ligand interactions. We describe how to analyze the bimodal optical-electrical data to improve upon the discrimination of antibody and ligand versus bound complex compared to electrical measurements alone. Example results for specific interaction detection are described for T-cell receptor-like antibodies (TCRmAbs) engineered to target peptide-presenting Major Histocompatibility Complex (pMHC) ligands, representing a model of target ligands presented on the surface of cancer cells. We also describe how to analyze the bimodal optical-electrical data to discriminate between specific and non-specific interactions between antibodies and ligands. Example results for non-specific interactions are shown for cancer-irrelevant TCRmAbs targeting the same pMHCs, as a control. These example results demonstrate the utility of the SANE sensor as a potential screening tool for ligand targets in cancer immunotherapy, though we believe that its potential uses are much broader.

Keywords: Antibody-ligand interactions; Dual modality nanosensing; Dual nanoholes; Nanopore translocations; Peptide major histocompatibility complexes (pMHCs); Plasmonic optical trapping; Solid-state nanopores; TCR-like monoclonal antibodies.

MeSH terms

  • Electrophoresis
  • Immunotherapy
  • Ligands
  • Nanopores*
  • Nanotechnology / methods
  • Neoplasms*

Substances

  • Ligands