预处理化疗增强CIK细胞对Lewis肺癌的抑制作用

摘要

目的 观察预处理化疗在小鼠Lewis肺癌模型中对细胞因子诱导的杀伤细胞(cytokine - induced killer cells,CIK cells)的抗肿瘤活性的增强作用,并探讨介导此增效作用的机制.方法 建立C57BL/6小鼠Lewis肺癌模型,以紫杉醇( Paclitaxel,PTX)联合顺铂(Cisplatin,DDP)作为预处理方案(TP方案),将荷瘤小鼠随机分为四组:对照组(给予生理盐水,normal saline,NS)、CIK组(给予CIK细胞)、TP组(给予TP方案)、TP - CIK组(TP方案预处理后联合CIK细胞).隔日测量肿瘤长短径监测肿瘤体积,观察各组治疗方案对Lewis肿瘤的抑制作用.分离小鼠肿瘤组织,分别行CD3、FoxP3( Forkhead box P3)分子免疫组化染色以评估肿瘤组织中T淋巴细胞、Treg细胞的浸润情况.利用绿色荧光蛋白(green fluorescence protein,GFP)转基因小鼠制备GFP+ CIK细胞,荧光显微镜追踪其体内迁移分布,观察预处理化疗对CIK细胞体内归巢功能的影响.结果 TP预处理化疗联合CIK细胞可明显抑制Lewis肺癌的生长(P＜0.05),而单独CIK细胞免疫治疗或TP化疗均不能抑制Lewis肿瘤的生长(P＞0.05).TP预处理化疗可增加CD3+T淋巴细胞至肿瘤组织的浸润,下调肿瘤组织中Treg细胞的比例,促进CIK细胞至肿瘤及脾脏组织的归巢.结论 TP预处理化疗可增强CIK细胞对Lewis肺癌的抑制作用,为TP预处理化疗联合CIK细胞免疫治疗的临床应用提供了实验基础与理论依据.%Objective To investigate the antitumor effect of cytokine - induced killer (CIK) cells induced by preconditioning chemotherapy and to elucidate the underlying mechanisms. Methods C57BL/6 mice were inoculated with Lewis cells to establish the murine lung carcinoma models and then randomly divided into four groups. Control group: given normal saline (NS) ; CIK group: treated with CIK cells; TP group: treated with TP regimen including paclitaxel (PTX) plus cisplatin (DDP); TP-CIK group: preconditioned with TP regimen followed by CIK cells. Tumor size was monitored as indicator of therapeutic response. Immunohistochemistry was performed to observe the intratumoral infiltration of CD3 + T lymphocytes and FoxP3 regulatory T (Treg) cells. The in vivo trafficking and homing ability of GFP+ CIK cells were observed by fluorescent microscopy. Results The combination of TP preconditioning chemotherapy and CIK cells significantly inhibited the growth of Lewis lung carcinoma ( P ＜ 0. 05 ) , whereas CIK therapy alone or DDP chemotherapy alone failed to inhibit tumor growth ( P ＞ 0. 05 ). The TP regimen increased the level of T lymphocytes in local tumor tissues, but exerted no influence on tumor microvessel density, decrease the percentages of Treg cells in tumor tissues and augment the homing ability of infused CIK cells into tumor and spleen tissues. Conclusion TP preconditioning chemotherapy can enhance the antitumor activity of CIK cell therapy in Lewis lung carcinoma model.