目的：探讨含未甲基化胞嘧啶鸟嘌呤(CpG)序列的细菌寡核苷酸（CpG oligodeoxynucleotide,CpG ODN）免疫佐剂在增强黑色素瘤抗原基因-3(melanoma antigen gene -3，MAGE-3)抗原肽致敏DC抗膀胱肿瘤细胞的作用及其分子机制。方法：采用Ficoll 法从健康志愿者HLA-A2 型外周血中分离单个核细胞，常规方法诱导培养制备成熟DC。MTT法检测不同方式（MAGE-3、CpG ODN、MAGE-3+CpG ODN 和无关抗原对照）致敏DC 对T 淋巴细胞增殖和CTL 对靶细胞BIU-87 的杀伤作用。CpGODN+MAGE-3 抗原肽致敏DC抗裸鼠BIU-87 膀胱癌细胞移植瘤治疗7、11 d 测定移植瘤质量变化，MTT和Western blotting 法分别检测移植瘤细胞的增殖水平及其凋亡蛋白表达的变化。结果：CpG ODN+MAGE-3 抗原肽致敏DC能够促进T淋巴细胞增殖（P<0.05），并显著提高活化T淋巴细胞的CTL对靶细胞BIU-87 的杀伤活性（P<0.05）。体内实验表明，致敏DC治疗7、11 d 的各组移植瘤质量均明显降低（均P<0.05），移植瘤的增殖能力下降也较明显（P<0.05）；与其他致敏DC方式相比较，尤以CpG ODN+MAGE-3 致敏DC组在治疗11 d 时的移植瘤质量降低非常显著（P<0.01），且明显促进荷瘤小鼠脾脏单个核细胞的增殖能力（P<0.01）；该组在治疗第3 天起移植瘤组织Bcl-2 表达水平明显降低、Bax水平明显升高（均P<0.05 或P<0.01）。结论：CpG ODN能促进MAGE-3 抗原肽致敏DC对膀胱癌BIU-87 细胞的抑制作用，为膀胱癌DC疫苗的临床应用提供了实验依据。

Objective: To investigate the role of CpG ODN (CpG oligodeoxynucleotide) adjuvant in enhancing the anti-bladder cancer response induced by MAGE-3 (melanoma antigen gene -3) antigen and its molecular mechanism. Methods: Mononuclear cells were isolated from HLA-A2 type peripheral blood of healthy donors by Ficoll method to prepare mature DC by conventional means. DC surface markers were detected by flow cytometry. MTT assay was used to detect the promotion effect of DCs sensitized by different means (MAGE-3, CpGODN, MAGE-3+CpG ODN, irrelevant control antigen) on the proliferation of T lymphocytes and the killing effect of CTL on BIU-87 tumor cells. The tumor mass of nude mice bearing BIU-87 bladder cell xenograft were examined on Day 7 and 11 after CpG ODN+MAGE-3 sensitized DC treatment. The expression of Bcl-2/Bax protein was detected by Western blotting while the proliferation level of xenograft cells was detected by MTT assay. Results: DCs sensitized by CpG ODN combined with MAGE-3 antigenic peptides could promote the proliferation of T lymphocytes and significantly enhance the killing effect of CTL on target BIU-87 cells (P<0.05). Compared with other sensitized DCs, in vivo experiments showed that 7 and 11 days after treatment, both the tumor volume and weight were significantly reduced (all P<0.05), and the proliferation ability of xenograft tumor was decreased (P<0.05). Compared with other sensitization means, CpG ODN+MAGE-3 especially exhibited obvious inhibitive effect on tumor growth on Day 11, and significantly promoted the proliferation of splenic monocytes of tumor bearing mice (P<0.01); moreover, Bcl-2 expression in xenograft tissues significantly decreased（P<0.01）while Bax expression significantly increased（P<0.05 or P<0.01）on Day 3 after treatment. Conclusion:CpG ODN can promote the inhibitory effect of MAGE-3 sensitized DC on bladder cancer BIU-87 cells, which will provide experimental basis for clinical application of DC vaccine in bladder cancer treatment.

国家自然科学基金资助项目（No.31500056）；山东省高等学校科技计划资助项目(No.J11LF03)；济宁市科技助推新旧动能转换计划资助项目（No.2017SMNS001）；济宁医学院青年教师科研扶持基金资助项目（JNo.Y2017KJ010）