Antigen-Multimers: Specific, Sensitive, Precise, and Multifunctional High-Avidity CAR-Staining Reagents

Antigen-multimers are high-avidity CAR-staining reagents. We reported the specificity of antigen-multimers in distinguishing CAR-T from non-CAR-T cells from patient biospecimens by performing paired single-cell RNA- and TCR-sequencing on sorted CAR-T patient samples. Overall design: Peripheral blood mononuclear cells from a patient with diffuse large B-cell lymphoma and treated with axicabtagene ciloleucel was taken at day 21 post-infusion. The sample was stained with anti-CD3 antibodies and CD19-tetramers (for CAR detection) for sorting. 12,000 sorted endogenous CD3+Tet- ("Endo-T") and 7,853 sorted therapeutic CD3+Tet+ ("CAR-T") cells were separately partitioned into droplets for single-cell paired RNA-seq and TCR-seq profiling.