PT  - JOURNAL ARTICLE
AU  - Kristen E. Pauken
AU  - Osmaan Shahid
AU  - Kaitlyn A. Lagattuta
AU  - Kelly M. Mahuron
AU  - Jacob M. Luber
AU  - Margaret M. Lowe
AU  - Linglin Huang
AU  - Conor Delaney
AU  - Jaclyn M. Long
AU  - Megan E. Fung
AU  - Kathleen Newcomer
AU  - Katy K. Tsai
AU  - Melissa Chow
AU  - Samantha Guinn
AU  - Juhi R. Kuchroo
AU  - Kelly P. Burke
AU  - Jason M. Schenkel
AU  - Michael D. Rosenblum
AU  - Adil I. Daud
AU  - Arlene H. Sharpe
AU  - Meromit Singer
TI  - Single-cell analyses identify circulating anti-tumor CD8 T cells and markers for their enrichment
AID  - 10.1101/2020.09.30.294959
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.09.30.294959
4099  - http://biorxiv.org/content/early/2020/10/01/2020.09.30.294959.short
4100  - http://biorxiv.org/content/early/2020/10/01/2020.09.30.294959.full
AB  - The ability to monitor anti-tumor CD8+ T cell responses in the blood has tremendous therapeutic potential. Here, we used paired single-cell RNA sequencing and T cell receptor (TCR) sequencing to detect and characterize “tumor matching” (TM) CD8+ T cells in the blood of mice with MC38 tumors and melanoma patients using the TCR as a molecular barcode. TM cells showed increased activation compared to non-matching T cells in blood, and appeared less exhausted than matching counterparts in tumor. Importantly, PD-1, which has been used to identify putative circulating anti-tumor CD8+ T cells, showed poor sensitivity for identifying TM cells. By leveraging the transcriptome we identified candidate cell surface marker panels for TM cells in mice and melanoma patients, and validated NKG2D, CD39, and CX3CR1 in mice. These data demonstrate that the TCR can be used to identify tumor-relevant populations for comprehensive characterization, reveal unique transcriptional properties of TM cells, and develop marker panels for tracking and analysis of these cells.Summary Using single-cell RNA-sequencing coupled with TCR sequencing, we detected CD8+ T cell clones shared between blood and tumor in mice and melanoma patients, characterized these matching clones in blood and tumor, and identified potential biomarkers for their isolation in blood.Competing Interest StatementThe authors declare the enclosed potential conflicts of interest. M.D.R. is a founder of TRex Bio and Sitryx Bio and receives research funding from Abbvie, LEO Pharma, and TRex bio. A.I.D. has funds from Merck, Oncosec, BMS, Roche, Genentech, Pfizer, Incyte, Novartis and Checkmate, is on advisory boards for Xencor, Pfizer, Array, has stock in TRex, SQZ bio., and patents with Oncosec on Gene Therapy of melanoma. A.H.S. has patents on the PD-1 pathway licensed by Roche/Genentech and Novartis, consults for Novartis, is on the scientific advisory boards for Surface Oncology, Sqz Biotech, Elstar Therapeutics, Elpiscience, Selecta and Monopteros, and has research funding from Merck, Novartis, Roche, and Quark Ventures. K.K.T discloses institutional research funding from Array/Pfizer, BMS, Oncosec, Regeneron, and Replimune. From August 4th 2020, MS is an employee of Guardant Health. The authors have no additional financial conflicts of interest to disclose.