LAUSR

Background: Novel experimental therapies, including immunotherapy and gene immunotherapy, are real hope for patients with NSCLC. Generally, current clinical trials are ineffective, it is assumed that tumor induces harmful immunoediting of alveolar lymphocytes (AL). Aim: Examination of AL phenotypic properties in NSCLC, with special attention to the markers of T cell cytotoxicity. Methods: BAL was harvested from tumor-free lung region in 17 patients with NSCLC and 9 controls (all smokers). AL were phenotyped for major subsets and for markers of effector/memory/cytotoxicity function both in Th and Tc cells, including FasL, TRAIL and granzyme B expression. AL apoptosis rate was assessed by three parallel techniques, incl. cell cycle analysis and TUNEL assay. Results: We found higher CD4/CD8 ratio in NSCLC, as compared to controls (1.2±0.3 vs 0.9±0.7, median±SEM). AL of NSCLC patients showed elevated expression of FasL (especially on CD4+ cells: 13±7.5 vs 2.3±1.7%, p Conclusioons. AL in NSCLC are activated and reveal increased cytotoxic potential (FasL+ cells, TRAIL+ cells, NK cells) and local resistance to apoptosis. Markers of cytotoxicity were expressed on both Th and Tc cells. Immune therapy should be considered as a powerful option in early NSCLC stage, before tumor-derived immunosuppression develops.