Lung carcinoma - Analysis of T helper type 1 and 2 cells and T cytotoxic type 1 and 2 cells by intracellular cytokine detection with flow cytometry

BACKGROUND. T helper type 1 cells (Th1), Th2, T cytotoxic type 1 cells (Tc1 ), and Tc2 play important immunoregulatory roles. Some recent studies have demonstrated that an elevated level of type 2 cytokines, such as interleuki n-10, contributes to the ability of cancer cells to escape immunosurveillan ce. However, the impacts of Th1, Th2, Tc1, and Tc2 on tumor immunity are un clear. METHODS. The authors evaluated the ratio of Th1 to Th2 and that of Tc1 to T c2 among peripheral blood lymphocytes (PBL), regional lymph node lymphocyte s (RLNL), and tumor-infiltrating lymphocytes (TIL) in 46 nonsmall cell lung carcinoma patients who had just undergone surgery; the evaluation involved detecting the intracellular interferon-gamma and interleukin-4 production with 3-color flow cytometry. They also evaluated the same ratios in the per ipheral blood lymphocytes of 29 lung carcinoma patients with or without rec urrence after surgery, and in the peripheral blood of normal volunteers. RESULTS. The Th1-to-Th2 and Tc1-to-Tc2 ratios were significantly elevated i n the tumor tissues. These ratios in the TIL were significantly elevated in the groups of patients with squamous cell carcinoma and a history of smoki ng. The Th1-to-Th2 and Tc1-to-Tc2 ratios were significantly depressed in th e PBL of the patients with tumor recurrences. CONCLUSIONS. A favorable Th1- and Tc1-dominant pathway is induced in the tu mor tissues of operable patients, but their pathway can be expected to shif t from Th1 or Tcl to Th2 or Tc2 with the progression of cancer. Cancer 1999 ;85:2359-67. (C) 1999 American Cancer Society.