Skip to main content
. Author manuscript; available in PMC: 2022 May 9.
Published in final edited form as: J Phys Chem Lett. 2021 Aug 4;12(31):7566–7573. doi: 10.1021/acs.jpclett.1c02240

Figure 1.

Figure 1.

Cartoon details of SMSC and SM assays. (A) SMSC is designed to measure the lifetime of a single αβ TCR/CAR-pMHC bond on the surface of a T-cell as a function of force. A 3500 bp DNA strand is connected to an optically trapped bead through a dig–antidig interaction. A single pMHC molecule which interacts with the TCR/CAR receptor is linked to the other end of the DNA strand by half of an antibody. The inset in (A) shows a photomicrograph (top view) of a T-cell interacting with a pMHC-coated bead during SMSC (yellow box). (B) SM assay to study the interaction between purified CAR/control antibody and pMHC on the cover glass surface. CAR/control antibody was bound to the PEG coverslip through disuccinimidyl suberate (DSS) and biotinylated protein G and streptavidin (SA). An antidigoxigenin-coated bead-3500 bp DNA–pMHC slurry was used to form tethers. A typical trap stiffness of 0.1–0.2 pN/nm was used for the experiment. Bead displacement from the trap center was measured until bond rupture. Force was calculated by multiplying ΔX (bead displacement from trap center) and trap stiffness. Cartoons are not to scale.