C型CpG单链寡核苷酸对肿瘤疫苗抑瘤效果的增强作用

目的：研究C型CpG单链寡脱氧核苷酸（CpG ODN）对肿瘤疫苗抑瘤效果的增强作用.方法：利用体外淋巴细胞增生实验和病毒保护实验确定新C型CpG ODN, 采用小鼠体内抑瘤实验观察CpG ODN对肿瘤疫苗HSP65-MUC1重组蛋白抑制MUC1阳性肿瘤生长的增强作用, 并对小鼠血清中抗HSP65-MUC1抗体的类型进行了初步鉴定.结果：自行设计的CpG ODN BW005能刺激人PBMC和小鼠脾细胞增生,其刺激后的培养上清具有保护Vero E6细胞免受VSV感染的作用, 属于新型C型CpG ODN.将BW005与HSP65-MUC1联合应用于C57BL/6小鼠后, MUC1阳性肿瘤的发生明显延缓（平均44.8 d）, 其终末肿瘤发生率最低（33.33%）;荷瘤小鼠的生存期明显延长（平均49.5 d）, 其终末生存率最高（66.67%）.小鼠血清中抗HSP65和抗MUC1的IgG2a抗体水平增加.结论：C型CpG ODN可以增强肿瘤疫苗HSP65-MUC1的抑瘤效果, 考虑与小鼠体内Th1环境的形成有关.

Enhancement of HSP-MUC1 antitumor activity by type C CpG-ODN BW005

AIM: To investigate the enhancement of anti-tumor effect of HSP-MUC1 by self-designed type C CpG-ODN BW005. METHODS: The immunostimulatory effect of CpG-ODN BW005 was detected by IFN protection assay and (3)H proliferation assay in vitro. Sixty C57BL/6 mice were separated into 5 groups randomly, including Sodium Chloride control, HSP-MUC1 control, HSP-MUC1/1585, HSP-MUC1/1826 and HSP-MUC1/BW005. Mice were injected s.c. with agents on day 0, 14 and 28 and were implanted MUC1-EL4 tumor cells s.c. on day 33. Tumor growth and murine death were recorded. Blood was collected in 57 day from tail vein. Subtype of anti-HSP and anti-MUC1 IgG in serum was detected by indirect ELISA. RESULTS: CpG-ODN BW005 could stimulate the proliferation of hPBMC and mice spleoncyte and IFNalpha production. HSP-MUC1/BW005 postponed tumor development, with the average tumor-developed day of 44.8, and prolonged the survival of mice with the average survival day of 49.5. Moreover, final tumor-developed rate of this group was 33.33%, which was the lowest; final survival rate of this group was 66.67%, which was the highest. Levels of anti-HSP and anti-MUC1 IgG2a in HSP-MUC1/CpG-ODNs group were enhanced. CONCLUSION: CpG-ODN BW005, a kind of type C CpG-ODN, could enhance the anti-tumor effect of HSP-MUC1.