Abstract 

Systematic interrogation of tumor-infiltrating lymphocytes is key to the development of immunotherapies and the prediction of their clinical responses in cancers. Here, we perform deep single-cell RNA sequencing on 5,063 single T02cells isolated from peripheral blood, tumor, and adjacent normal tissues from six hepatocellular carcinoma patients. The transcriptional profiles of these individual cells, coupled with assembled T02cell receptor (TCR) sequences, enable us to identify 11 T02cell subsets based on their molecular and functional properties and delineate their developmental trajectory. Specific subsets such as exhausted CD8 + T02cells and Tregs are preferentially enriched and potentially clonally expanded in hepatocellular carcinoma (HCC), and we identified signature genes for each subset. One of the genes, layilin, is upregulated on activated CD8 + T02cells and Tregs and represses the CD8 + T02cell functions in02vitro. This compendium of transcriptome data provides valuable insights and a rich resource for understanding the immune landscape in cancers. Copyright 08 2017 Elsevier Inc. All rights reserved.