Immunological profiling of tumor-infiltrating CD8+ T lymphocytes in non-small cell lung cancer, head and neck squamous cell carcinoma, breast cancer, and renal cell cancer

To explore whether the variation in clinical response to immune checkpoint blockade (ICB) reflects intrinsic characteristics of tumor-infiltrating lymphocytes (TIL), TILs from multiple tumor types were analyzed by multiparameter flow cytometry. Recent work identified CD39+CD103+ double positive (DP) CD8 TIL as tumor-reactive, therefore we assessed this phenotype in primary NSCLC (n=28), BCa (n=23), HNSCC (n=23), and RCC (n=23) specimens. TILs from NSCLC and HNSCC had significantly higher frequencies of DP T cells than BCa and RCC (NSCLC: median=34.2, IQR=15.0–53.8%; HNSCC: median=28.6%, IQR=13.5–44.5%), while TILs from BCa and RCC had low frequencies of DP T cells (BCa: median=2.4%, IQR=1.1–3.9%; RCC: median=4.2%, IQR=1.5–16.6%). Additionally, DP cells in NSCLC and HNSCC were co-expressed immune checkpoint markers PD-1, TIM-3, and LAG-3 at a higher frequency than RCC or BCa (P Supported by GlaxoSmithKline and the Providence Portland Medical Foundation