Utilizing scRNA/TCRseq, CITEseq, and a novel assay for cell-bound anti-PD-1 to study the dynamics of T cells targeted by anti-PD-1, Nose and Yasumizu et al. first found that abundance of progenitor-exhausted CD8+ T cells (Tpex) in metastasis-free lymph nodes (LNs), but not tumors or metastatic LNs, correlated with better prognosis in patients with anti-PD-1-naive gastric cancer. Anti-PD-1 promoted the proliferation of anti-PD-1high-bound Tpex in LNs, and clonotypes overlapped with intratumoral anti-PD-1-bound exhausted T cells (Tex), suggesting that anti-PD-1high-bound Tpex migrate to the tumor, where they differentiate into Tex.

Contributed by Ute Burkhardt

ABSTRACT: While progenitor-exhausted T cells (Tpex) expressing TCF1 and PD-1 are crucial for the therapeutic effect of immune checkpoint inhibitors (ICIs) with therapeutic anti-PD-1 antibodies (aPD-1), the dynamics of ICI-bound Tpex are not fully understood. In this study, we investigate ICI-bound T cells in detail using combined sequencing analysis at the single-cell level. By analyzing samples from gastrointestinal cancer patients with or without ICI treatment, we find that Tpex are enriched in proximal lymph nodes (LNs) and proliferate at a high rate after ICI treatment. Importantly, aPD-1 high-bound Tpex in LNs share T-cell receptor clonotypes with intratumoral exhausted CD8(+) T cells (Tex), suggesting their migration to tumor sites after ICI treatment. This study thus provides new insights into how ICIs enhance anti-tumor immunity by acting on Tpex in LNs, deepening our understanding of the cellular mechanisms underlying ICI therapy.

Author Info: (1) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan. Department of Clinical Research in Tumor Immunology, Graduate Sch

Author Info: (1) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan. Department of Clinical Research in Tumor Immunology, Graduate School of Medicine, The University of Osaka, Suita, Japan. (2) Experimental Immunology, WPI Immunology Frontier Research Center, The University of Osaka, Suita, Japan. Integrated Frontier Research for Medical Science Division, Institute for Open and Transdisciplinary Research Initiatives (OTRI), The University of Osaka, Suita, Japan. (3) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan. tsaito@gesurg.med.osaka-u.ac.jp. Department of Clinical Research in Tumor Immunology, Graduate School of Medicine, The University of Osaka, Suita, Japan. tsaito@gesurg.med.osaka-u.ac.jp. (4) Experimental Immunology, WPI Immunology Frontier Research Center, The University of Osaka, Suita, Japan. (5) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan. Department of Clinical Research in Tumor Immunology, Graduate School of Medicine, The University of Osaka, Suita, Japan. (6) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan. Department of Clinical Research in Tumor Immunology, Graduate School of Medicine, The University of Osaka, Suita, Japan. (7) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan. (8) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan. (9) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan. (10) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan. (11) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan. (12) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan. (13) Department of Clinical Research in Tumor Immunology, Graduate School of Medicine, The University of Osaka, Suita, Japan. Pharmaceutical Research Division, Shionogi & Co., Ltd., Toyonaka, Japan. (14) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan. (15) Department of Pathology, Institute of Medical Science (Medical Research Center), Tokyo Medical University, Tokyo, Japan. (16) Experimental Immunology, WPI Immunology Frontier Research Center, The University of Osaka, Suita, Japan. Department of Basic Research in Tumor Immunology, Graduate School of Medicine, The University of Osaka, Osaka, Japan. (17) Experimental Immunology, WPI Immunology Frontier Research Center, The University of Osaka, Suita, Japan. (18) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan. Department of Clinical Research in Tumor Immunology, Graduate School of Medicine, The University of Osaka, Suita, Japan. (19) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan. (20) Department of Gastroenterological Surgery, Graduate School of Medicine, The University of Osaka, Suita, Japan.