Abstract 2847: Simultaneous TCR and transcriptomic sequencing of single Tcells defines biological subtypes in pancreatic cancer for adoptive Tcell therapy

Abstract Pancreatic ductal adenocarcinoma (PDAC) is a highly fatal tumor-type with very few effective treatment strategies. Attempts to improve outcomes using immune checkpoint blockade therapy have also failed, likely because the overall Tcell infiltration in this tumor-type is low. Despite this, the presence of CD3+CD8+ tumor-infiltrating lymphocytes (TIL) in PDAC is associated with improved survival outcomes, suggesting that other immune-based strategies could be more successful. Here, we examine ex vivo tumor-infiltrating Tcell expansion for adoptive Tcell therapy (ACT) as a potential strategy for treating PDAC. The focus of this study is to understand the transcriptional states of Tcells in the pancreas and PDACs and how they change with ex vivo expansion and re-infusion into patients as treatment strategy. We have performed both single cell transcriptome and TCR sequencing (scRNA-TCRseq) on 54,579 Tcells from 8 human PDAC samples and the ex vivo grown TIL from a subset of 6 patients and found 13 purported substates. Through TCR tracking of the Tcell clonotypes, we find that the expansion protocol is able to expand Tcells found in many different Tcell states in the primary tumor. Furthermore, we compared our thirteen tumor-infiltrating substates with 41,935 Tcells from two other independent single cell studies across 71 samples, and confirmed our substates to be present across all datasets. Citation Format: Aislyn Schalck, Donastas Sakellariou-Thompson, Marie-Andrée Forget, Emi Sei, Tara Hughes, Shanshan Bai, Min Hu, Tapsi Kumar, Mark Hurd, Matthew Katz, Chine-Wei Tzeng, Shubham Pant, Milind Javle, Anirban Maitra, Cara Haymaker, Michael Kim, Nicholas Navin, Chantale Bernatchez. Simultaneous TCR and transcriptomic sequencing of single Tcells defines biological subtypes in pancreatic cancer for adoptive Tcell therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2847.