肺癌模型小鼠肿瘤和主要免疫器官组织中调节性 T 细胞和NK 细胞的数量变化及其意义

目的：探讨肺癌小鼠CD4⁺CD25⁺Foxp3⁺调节性T细胞（Treg）和自然杀伤细胞（NK）在外周免疫器官和肿瘤组织中数量的变化，阐明其对肿瘤发展的影响。方法：C57BL/6小鼠分为Lewis肺癌细胞系（LLC）注射组和正常对照组，LLC注射组小鼠采用LLC腋窝注射制备皮下肿瘤模型，正常对照组小鼠采用生理盐水等量注射。采用细胞表面和细胞内特异荧光抗体染色和流式细胞术检测肺癌小鼠脾脏、淋巴结和肿瘤组织中CD4⁺CD25⁺T细胞、Treg细胞及脾脏组织中NK细胞数量。结果：与正常对照组比较，LLC注射组小鼠脾脏和淋巴结中CD4⁺CD25⁺ T细胞占CD4⁺T细胞比例及Foxp3⁺在CD4⁺CD25⁺T细胞中的表达比例明显升高（P < 0.05），CD4⁺CD25⁺Foxp3⁺ Treg细胞数量也明显升高（P < 0.05或P < 0.01）。LLC接种组小鼠肿瘤组织中CD4⁺CD25⁺ T细胞占CD4⁺T细胞比例及Foxp3⁺在CD4⁺CD25⁺T细胞中的表达比例明显高于脾脏和淋巴结（P < 0.05）。与正常对照组比较，LLC注射组小鼠脾脏组织中NK细胞比例明显降低（P < 0.05）。结论：肺癌小鼠主要免疫脏器官组织中Treg细胞比例和数量升高，NK细胞比例降低，其可促进肿瘤发展，抑制机体对肿瘤细胞的免疫应答。

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

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 .