混合热休克蛋白/肽疫苗与IL-2联合免疫治疗肉瘤的实验研究

Experimental study of mixed heat shock protein/peptide combined with interleukin-2 for treatment of sarcoma in mice

目的观察混合热休克蛋白/肽(mHSP/P)疫苗、环磷酰胺(Cy)及重组人IL-2(rhIL-2)联合免疫治疗小鼠肉瘤的效果。方法取小鼠S180细胞肉瘤组织,经层析分离获得混合mHSP/P疫苗,进行常规蛋白质印迹鉴定。S180细胞接种至小鼠皮下后第2天开始实验,将小鼠按mHSP/P、Cy、rhIL-2药物组合、疗程和剂量的不同依次分为B～I组,以及给予生理盐水的A组(对照组)。自肿瘤移植后至第45天,观察计算肿瘤体积;以肿瘤移植后3个月仍无瘤生长或肿瘤逐渐缩小至消失为标准,观察各组小鼠的无瘤生存情况,并进行平均生存期比较;以对照组的肿瘤体积为参照,计算第35天各组小鼠肿瘤的生长抑制率。结果蛋白质印迹分析结果显示所获目的蛋白为含有HSP110、HSP70、HSP60、Gp96的混合mHSP疫苗。3种药物联合应用的治疗效果明显优于单用mHSP/P疫苗,且多疗程较单一疗程疗效好,其中rhIL-2的最佳治疗剂量为5×104～1×105IU/只,并可使30%的小鼠肿瘤消退而长期生存(治愈),平均生存期延长22～26d,肿瘤生长抑制率为65%～76%。结论mHSP疫苗与适量rhIL-2以及小剂量Cy联合应用为临床肉瘤治疗新的免疫治疗方案提供了实验基础。

Objective To investigate the anti-tumor effects of mixed heat shock protein/peptides combined with interleukin-2 and cyclophosphamide in mouse sarcoma. Methods Mixed heat shock protein/peptides compound were extracted from mouse sarcoma cell line S180 by molecular chromatography Saphacryl 200,identified by SDA-PAGE and Western blot,BALB/C mice were immunized by mixed heat shock protein/peptides with different quantity,S180 sarcoma cell line was grafted before vaccine and immune therapy in BALB/C,the long time survival,tumor relapse and tumor growth inhibition rates were examined. Results Mixture heat shock protein/peptides and HSP60,HSP70,Gp96 were isolated by chromatography and affinity chromatography,Mice immunized by mixture heat shock protein/peptides and interleukin-2 and cyclophosphamide has protected results than only use HSP/P vaccine.Tumor relapsed and long time survival was 30%in the best modalit.Average survival time was significant longer than control group.The tumor growth inhibition rates was 65%-76%. Conclusion These animal vaccination/immunization strategies show that heat shock protein/peptides mixture combined with cyclophosphamide and IL-2 can reduce tumor burden,it may be possible to develop a new modality for clinical treatments of sarcoma.