Tumour-Infiltrating Lymphocytes in Non-Small Cell Lung Cancer Are Activated T Lymphocytes

Abstract

This study was carried out in order to investigate the local immune reaction of tumour-infiltrating lymphocytes (TILs) in the primary tumours of non-small cell lung carcinomas. Thirty non-small cell lung cancer ( NSCLC) patients were included. The tumour tissue was taken at thoracotomy and monocellular suspension of the tumour was obtained by mechanical disaggregation. Dual-coloured flow cytometric analysis of TILs and their corresponding peripheral blood lymphocytes (PBLs) was performed. Tumour- infiltrating lymphocytes contained significantly higher proportions of CD 3(+) T lymphocytes and CD8(+) T lymphocytes than the corresponding PBLs ( 82.0%+/-13.9% vs 66.3%+/-10.6% for CD3, P<0.001; 39.0%+/-18.4% vs 26.4%+/- 5.2% for CD8, P<0.001). Tumour-infiltrating lymphocytes contained significantly higher proportions of activated memory lymphocytes than PBLs did (9.8%+/-8.6% vs 1.3%+/-1.5% for CD25, P<0.001; 40.5%+/- 30.2% vs 10.2 %+/-14.8% for CD71, P<0.001; 75.5%+/-11.9% vs 28.6%+/-9.8% for HLA-DR, P<0 .001). These findings were also found in both CD4(+) TILs and CD8(+) TILs. The TILs of NSCLC contained higher proportions of T lymphocytes and CD8(+ ) lymphocytes than their corresponding peripheral bloods. The proportions of activated memory lymphocytes were also significantly higher in the TILs , both in CD4(+) TILs and CD 8(+) TILs, than the corresponding PBLs.