Exhausted intratumoral Vd2- ?d T cells in human kidney cancer retain effector function [scRNA-seq]

Gamma delta (?d) T cells reside within human tissues including tumors, but their role in mediating anti-tumor response with immune checkpoint inhibition is unknown. Using single-cell approaches, we found that kidney cancers are infiltrated by diverse Vd2- ?d T cells, with equivalent representation of Vd1+ and Vd1- cells, that are distinct from ?d T cells found in normal human tissues. These tumor-resident Vd2- T cells can express the transcriptional program of exhausted alpha beta (ab) CD8+ T cells as well as canonical markers of terminal T cell exhaustion including PD-1, TIGIT and TIM-3. While Vd2- ?d T cells have blunted IL-2 production, they retain expression of cytolytic effector molecules and costimulatory receptors like 4-1BB. Exhausted Vd2- ?d T cells are comprised of three distinct populations that lack TCF-7, are clonally expanded, express of cytotoxic molecules, and possess multiple Vd2- TCRs. Human tumor-derived Vd2- ?d T cells maintain cytotoxic function and pro-inflammatory cytokine secretion in vitro. The transcriptional program of Vd2- T cells in pre-treatment tumor biopsies predicted subsequent clinical responses to PD-1 blockade in vivo in cancer patients. Thus, Vd2- ?d T cells within the tumor microenvironment can contribute to anti-tumor efficacy. Overall design: Tumor samples were obtained from resection surgery from 6 adult patients with histologically confirmed renal cell carcinoma (RCC). Samples were minced and digested, then FACS-sorted for live gd, CD4, and CD8 T cells. Samples were then pooled by cell type (to be demultiplexed later via Demuxlet using separately constructed bulk RNA libraries). Libraries were constructed using 10x Genomics Chromium 5' (v1) and 10x Genomics Chromium V(D)J kit (PN-1000005) and sequenced on an Illumina NovaSeq 6000.