荷载CSCs抗原的DC疫苗联合小剂量TP治疗乳腺癌小鼠效果观察

摘要

目的 研究荷载肿瘤干细胞(CSCs)抗原的树突状细胞疫苗联合小剂量TP(紫杉醇+顺铂)治疗小鼠乳腺癌的疗效.方法 利用ALDEFLUOR染料从小鼠乳腺癌细胞系4T1中分选出ALDH high肿瘤干细胞,将CSCs制备成细胞裂解液加载在DC细胞上制备成CSCs-DC疫苗.利用小鼠乳腺癌细胞系4T1接种Balb/c小鼠建立小鼠乳腺癌模型,随机分成磷酸盐缓冲液组(PBS组)、紫杉醇+顺铂组(TP组)、CSCs-DC疫苗组(CSCs-DC组)、CSCs-DC疫苗联合TP组(CSCs-DC+TP组),PBS组腹腔注射0.1 mL的PBS;TP组腹腔注射紫杉醇20 mg/kg,顺铂5 mg/kg;CSCs-DC组皮下注射CSCs-DC疫苗;CSCs-DC+TP组皮下注射CSCs-DC疫苗,腹腔注射紫杉醇20 mg/kg,顺铂5 mg/kg.观测各组肿瘤大小和小鼠生存期,实验终点取小鼠脾脏,体外培养激活后利用LDH细胞毒性实验测定细胞毒性T淋巴细胞(CTL)活性,ELISA法测定B细胞分泌IgG水平.结果 CSCs-DC+TP组肿瘤体积小于PBS组、TP组及CSCs-DC组(P均<0.05).小鼠生存期CSCs-DC+TP组最长,生存时间为(62.00±2.65)d,CSCs-DC组次之,生存时间为(52.00±1.00)d,TP组和PBS组生存时间分别为(46.00±2.00)、(35.00±1.00)d.CSCs-DC+TP组小鼠脾脏中CTL活性和B细胞分泌IgG水平最高,CSCs-DC组次之,TP组较CSCs-DC组和CSCs-DC+TP组低,但较PBS组高,差异有统计学意义(P均<0.01).结论 CSCs-DC疫苗联合小剂量TP治疗乳腺癌小鼠较CSCs-DC疫苗和TP单用效果好.%Objective To study the therapeutic effect and mechanism of cancer stem cells (CSCs)antigens-loaded dendritic cell (DC)vaccine combined with low-does TP (paclitaxel and cisplatin)in treatment of breast cancer in mice. Methods We sorted out the CSCs from breast cancer cell lines (4T1)by using ALDEFLUOR. Bone marrow-derived DCs were pulsed with CSCs lysate to generate CSCs-DC vaccine. The Balb/ c mice were inoculated with the heterogeneous 4T1 tumor cells by subcutaneous injection to make the mouse breast cancer models. The models were then divided into four groups:PBS group which was administrated PBS,TP group which was injected with 20 mg/ kg paclitaxel and 5 mg/ kg cis-platin intraperitoneally,CSCs-DC vaccine group (CSCs-DC group)which was administrated CSCs-DC vaccine by subcuta-neous injection,and the CSCs-DC vaccine + TP group (CSCs-DC + TP group)which was administrated CSCs-DC vaccine by subcutaneous injection and was injected with 20 mg/ kg paclitaxel and 5 mg/ kg cisplatin intraperitoneally. Tumor vol-umes were measured and survival was monitored. At the end of the experiment,the spleens in mice were harvested,the cy-totoxic lymphocyte (CTL)activity was measured by using LDH cytotoxicity assay,and IgG levels secreted by B cells was measured by ELISA. Results The tumor size in the CSCs-DC + TP group was less than that of the PBS group,the TP group and the CSCs-DC group (P < 0. 05). The average survival time of the CSCs-DC + TP group was (62. 00 ± 2. 65)d and was the longest,the average survival time of CSCs-DC group was (52. 00 ± 1. 00)d,the average survival time of TP group and PBS group were (46. 00 ± 2. 00)d and (35. 00 ± 1. 00)d,respectively. The CTL activity and IgG levels se-creted by B cells in the CSCs-DC + TP group were the highest,the CSCs-DC group was the second,TP group was lower than the CSCs-DC group and the CSCs-DC + TP group,but was higher than the PBS group,and the difference was statisti-cally significant (P < 0. 01). Conclusion The therapeutic effect of CSCs-DC vaccine combined with low-dose TP in the treatment of the mouse breast cancer is better than CSCs-DC vaccine and TP alone.