Changes of number of regulatory T cells and NK cells in tumor tissue and main immune organs of murine models of lung cancer and their significances / 吉林大学学报(医学版)

ABSTRACT

Objective:To explore the changes of number of CD4+ CD25 + foxp3 + regulatory T cells (Treg)and natural killer cells (NK)in the peripheral immune organs and tumor tissue of the murine models of lung cancer,and to clarify their effects on the development of lung cancer.Methods:The C57BL/6 mice were divided into Lewis lung carcinoma cells (LLC)injection group and normal control group.The mice in LLC injection group were injected with LLC subcutaneously in the armpit to establish the tumor models,while the mice in normal control group were injected with the same amount of saline.The number of CD4+ CD25 + T cells,CD4+ CD25 + foxp3 + Tregs in the spleen,lymph nodes and lung cancer tissues,and the number of NK cells in the spleen tissue were labeled by cell surface or intracellular antibody staining,and detected by flow cytometry.Results:The ratios of CD4+ CD25 + T cells to CD4+ T cells,foxp3+ cells to CD4+ CD25 + T cells,and the number of CD4+ CD25 + foxp3 + Treg in the spleen and lymph nodes of the mice in LLC injection group were increased significantly compared with normal control group (P <0.05 or P <0.01).Moreover,the ratios of CD4+ CD25 + T cells to CD4+ T cells and foxp3 + cells to CD4+ CD25 + T cells in the tumor tissue were significantly higher than those in the spleen and lymph nodes of the mice in LLC injection group.However,the ratio of NK cells in the spleen tissue of the mice in lung cancer group was significantly decreased compared with normal control group (P <0.05).Conclusion:The increase of ratio and the number of Treg cells and the decrease of ratio of NK cells in the main immune organs of lung cancer mice may promote the development of tumor and inhibit the immune response to cancer cells in vivo .