目的： 探讨表达小鼠NKG2D配体之一视黄酸早期转录因子1ε （retinoic acid early transcript 1ε，RAE1ε）的原B淋巴细胞BaF3对乳腺癌细胞株4T1成瘤小鼠来源的髓系抑制性细胞（myeloid-derived suppressor cell，MDSC）功能的影响。 方法： 以小鼠原B淋巴细胞株BaF3为基础，构建表达RAE1ε的BaF3-RAE1ε细胞以及表达空质粒的BaF3-mock对照细胞。通过4T1原位肿瘤模型诱导产生CD11b + Gr-1 + MDSC，将BaF3-mock细胞和BaF3-RAE1ε细胞作为刺激细胞，分别与脾MDSC共培养，流式细胞术检测MDSC表面CD40、CD80、F4/80、CD11c的表达和MDSC内活性氧（ROS）的水平；ELISA法检测共培养上清液IL-10、IL-4和IFN-γ的含量；Griess法检测共培养上清液一氮化氮（NO）的浓度。磁珠分选共培养体系中的MDSC，检测裂解后精氨酸酶的活性；另外，将分选后的MDSC与抗CD3/抗CD28抗体活化的脾细胞共培养，CFSE法检测活化的CD3 + CD8 + Ｔ细胞增殖情况。 结果 ：成功获得4T1原位肿瘤模型来源的小鼠脾MDSC。与BaF3-mock细胞相比，BaF3-RAE1ε细胞刺激对MDSC分泌IL-4、IFN-γ、IL-10和NO的水平没有明显影响（P>0.05）；对MDSC表达CD40、CD80、F4/80、CD11c和ROS也没有显著影响（P>0.05）。与BaF3-mock细胞相比，BaF3-RAE1ε细胞刺激显著提高MDSC的精氨酸酶活性（156.166±1.209 vs 110.135±7.356, P<0.01），并明显增强MDSC对CD8 + T细胞增殖的抑制作用。 结论 ：RAE-1ε在体外增强4T1成瘤小鼠来源的MDSC的抑制功能

Objective: To explore effect of BaF3 primary B lymphocyte that expresses retinoic acid early transcript 1? (RAE1?), ligand of mouse NKG2D, on function of myeloid-derived suppressor cell (MDSC) originated from mouse. Methods: Based on mouse primary B lymphocyte BaF3 line, a BaF3-RAE1? cell that expressed RAE1? and a BaF3-mock control cell with empty plasmid were structured. CD11b + Gr-1 + MDSC was produced through introduc- tion of 4T1 tumor model in situ. Spleen MDSC was respectively co-cultured with BaF3-RAE1? cell and BaF3-mock cell that acted as stimulating cells. Flow cytometry assay was used to detect expressions of CD40, CD80, F4/80 , CD11c and content of reactive oxygen species (ROS) in the MDSC. ELISA assay was used to test contents of IL-10, IL-4 ans IFN-γ in supernatant of the co-culture. Concentration of nitric oxide (NO) in the supernatant was examed by Griess assay. Magnetic beads were used to separate the MDSC in the co-culture system, activity of arginase was detected after splitting. In addition, the separated MDSC co-culture with splenocyte activated by anti-CD3/CD28 an-tibody. Proliferation of the activated CD3 + CD8 + T cell was examed by CFSC assay. Results: The MDSC of mouse spleen derived from 4T1 in situ tumor model was successfully obtained. Comparing with the BaF3-mock cell, effect- ing of the BaF3-RAE1? cell stimulation on amounts of IL-4, IFN-γ, IL-10 and NO secreted by the MDSC was not significant (P>0.05), and on amounts of CD40, CD80, F4/80 ,CD11c and ROS expressed by the MDSC also not sig- nificant (P>0.05). Stimulation of the BaF3-RAE1? cell did more increase activity of arginase in the MDSC than that of the BaF3-mock cell obviously (156.166±1.209 vs 110.135±7.356, P<0.01), and evidently enhanced inhibitory effect of the MDSC on proliferation of CD8 + T cell. Conclusion: RAE1? could enhance inhibitory function in vitro of the MDSC derived from 4T1 mouse with tumor.

国家自然科学基金资助项目（No. 81373130，No.81001308）,江苏省自然科学基金资助项目（No. BK2010315）；扬州大学大学生创新创业训练计划资助项目