Determination Of γδT Cells And Total T Lymphocytes In Lung Cancer Patients

Objective:To investigate the effects of lung cancer and surgery on the quantity and functions ofγδT cells and total T lymphocytes, we checked the difference in the level ofγδT cells and total T lymphocytes between lung cancer patients and health population, lung cancer tissues and peficancerous normal tissues, before and after surgery, respectively.Methods:ExperimentⅠ:The peripheral blood monocytes were isolated from 124 preoperation patients with lung cancer and 56 health people respectively, and the flow cytometry assay was applied to determine the number ofγδT cells and total T lymphocytes among total peripheral blood monocyte population. In addition, the changes in the number of peripheral bloodγδT cells and total T lymphocytes were detected in 30 patients with lung cancer before or after surgery.ExperimentⅡ:The lung cancer tissues and peficancerous normal tissues were isolated from 40 postoperation patients and used to determine the change in the number of infiltratingγδT cells and total T lymphocytes.Experiment III:The infiltrating lymphocytes in tissues of lung cancer (expenmental group) and the peripheral blood monocyte (control) were isolated from lung cancer patients. The supernatant were collected after cells were cultured for 24h,48h and 72h. ELISA assay and MTT method were used respectively to determine the supertatant content ofγ-IFN and the killing effects of lymphocytes on lung cancer cell line NCI-H460.Results:ExperimentⅠ:For 124 patients before surgury, the average percentage ofγδT cell in the total peripheral blood monocytes is 3.76±2.81, which is significantly less than the percentage of 6.54±2.90 in health people(P<0.05). However, there is not statistical differnence in the number of total T lymphocytes between the two groups. Thirty lung cancer patients were selected randomly to detect the changes in the number of peripheral bloodγδT cells and total T lymphocytes before and after surgury. The results demonstrated that the perentage of peripheral bloodγδT cells and total T lymphocytes in patients were not associated with age and gender(P>0.05). For lung cancer patients after surgury, the percentage of peripheral bloodγδT cells is 7.01±4.27, which is distinctly higher than that before surgury(3.78±2.64, P>0.05). There is not significant change in the pencentage of T lymphocytes before or after surgury.ExperimentⅡ:For 40 lung cancer patients, the average percentage of infiltrating T lymphocytes in lung cancer tissues is 15.79±18.35, that is distinctly higher than the percentage of 7.54±12.06 in peficancerous normal tissues (P<0.05). For various groups with T satge, N stage, M stage, clinical stage, general classification and malignant pathological changes, there is statistical differnence in the percentage of T lymphocytes between the patient group and control group(P<0.05), while there is no significant difference in the percentage of total T lymphocytes between the patient group and control group (P>0.05).ExperimentaⅢ:ELISA assay was used to test the level of y-IFN in supernatant from infiltrating lymphocytes of lung cancer tissues. The results showed that y-IFN secreted by infiltrating lung cancer lymphocytes was abundant and increased over time. MTT assay was used to investigate the killing effects of infiltrating lymphocytes on lung cancer cell line NCI-H460. Our results showed the killing effect of experimental group (infiltrating lymphocytes) was 48.60±12.75%, which was much greater than that of control group (15.19±6.33%,P<0.01)at E/T of 10:1.Conclusion:The y8T cells in the peripheral blood of lung cancer patients are significantly lower than that of healthy people, suggesting the decreasing ofγδT cells plays an important role on the development of lung cancer. TheγδT in peripheral blood of patients after surgery are significantly higher than before, suggesting that removal of tumor antigen can make the infiltration y8T cells flow back into the blood by lymphatic. The infiltrationγδT cells in lung cancer tissues are significantly higher than that in adjacent tissues, suggesting that the ability of y8T cells to recognize tumor cells. Infiltrating lung lymphcells could kill tumor cells and might be the first major line of defense.