Circulating T Cell Subpopulations Correlate With Immune Responses at the Tumor Site and Clinical Response to PD1 Inhibition in Non-Small Cell Lung Cancer

Front Immunol. 2018 Aug 3;9:1613. doi: 10.3389/fimmu.2018.01613. eCollection 2018.


Agents targeting the PD1-PDL1 axis have transformed cancer therapy. Factors that influence clinical response to PD1-PDL1 inhibitors include tumor mutational burden, immune infiltration of the tumor, and local PDL1 expression. To identify peripheral correlates of the anti-tumor immune response in the absence of checkpoint blockade, we performed a retrospective study of circulating T cell subpopulations and matched tumor gene expression in melanoma and non-small cell lung cancer (NSCLC) patients. Notably, both melanoma and NSCLC patients whose tumors exhibited increased inflammatory gene transcripts presented high CD4+ and CD8+ central memory T cell (CM) to effector T cell (Eff) ratios in blood. Consequently, we evaluated CM/Eff T cell ratios in a second cohort of NSCLC. The data showed that high CM/Eff T cell ratios correlated with increased tumor PDL1 expression. Furthermore, of the 22 patients within this NSCLC cohort who received nivolumab, those with high CM/Eff T cell ratios, had longer progression-free survival (PFS) (median survival: 91 vs. 215 days). These findings show that by providing a window into the state of the immune system, peripheral T cell subpopulations inform about the state of the anti-tumor immune response and identify potential blood biomarkers of clinical response to checkpoint inhibitors in melanoma and NSCLC.

Keywords: PD1 and PDL1; T cells subpopulations; checkpoint blockade; lung cancer; melanoma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Antineoplastic Agents, Immunological / therapeutic use
  • B7-H1 Antigen / immunology
  • B7-H1 Antigen / metabolism
  • Biomarkers, Tumor
  • Carcinoma, Non-Small-Cell Lung / drug therapy
  • Carcinoma, Non-Small-Cell Lung / immunology*
  • Humans
  • Lung Neoplasms / drug therapy
  • Lung Neoplasms / immunology*
  • Male
  • Melanoma / immunology*
  • Middle Aged
  • Nivolumab / therapeutic use
  • Programmed Cell Death 1 Receptor / antagonists & inhibitors*
  • Programmed Cell Death 1 Receptor / immunology
  • Programmed Cell Death 1 Receptor / metabolism
  • Progression-Free Survival
  • T-Lymphocyte Subsets / immunology*
  • T-Lymphocyte Subsets / metabolism


  • Antineoplastic Agents, Immunological
  • B7-H1 Antigen
  • Biomarkers, Tumor
  • CD274 protein, human
  • PDCD1 protein, human
  • Programmed Cell Death 1 Receptor
  • Nivolumab