Abstract 3984: Full-length TCR and BCR repertoire analysis, integrated with mRNA and surface proteins characterization, in a tumor mouse model

Abstract Full-length TCR and BCR analysis with single-cell multiomic assays provides an understanding of immune responses, offering insights into the complete receptor structure and functionality that is crucial for accurately assessing the diversity and specificity of immune repertoires. Studying mouse immune cell heterogeneity can be achieved by simultaneous mRNA and surface protein profiling. However, when coupled with full-length TCR and BCR analysis, this integrated approach provides a more comprehensive understanding of immune responses and cellular function in healthy and diseased conditions. In this study, we used the MC38 colon carcinoma model to study T and B cell heterogeneity and clonotype diversity. We stained single-cell suspensions prepared from bone marrow, thymus, spleen and tumor tissues with 20 AbSeq (CITE-Seq) antibody oligos and sample-multiplexing tags. We then loaded 50, 000 isolated T and B cells into two lanes of an 8-lane microwell cartridge for single-cell capture by a single-cell analysis system. To aid in the simultaneous analysis of clonality and gene expression, we carried out library preparation using a full-length TCR/BCR multiomic assay and a mouse immune response panel. The combination of mRNA and protein expression confirmed the elevated expression of exhaustion and activation markers in tumor-infiltrating lymphocytes (TILs). We identified high-frequency clonotypes within TILs and tracked their frequency across other tissues. Tumor-burdened mice splenic T cells showed shared TCR combinations with TILs, which were absent in healthy tissue. The results show the ability to successfully profile T and B cell receptors using a full-length TCR/BCR multiomic assay in a mouse tumor model and the use of transcriptome, protein and TCR/BCR clonal information to investigate immune cell characteristics across multiple samples. For Research Use Only. Not for use in diagnostic or therapeutic procedures. BD, the BD Logo and BD Rhapsody are trademarks of Becton, Dickinson and Company or its affiliates. © 2023 BD. All rights reserved. NPM-2536 (v1. 0) 1023 Citation Format: Ali Rezvan, Xiaoshan Shi, Moen Sen, Stephanie Widmann, Aaron Tyznik. Full-length TCR and BCR repertoire analysis, integrated with mRNA and surface proteins characterization, in a tumor mouse model abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 3984.