【摘要】 目的探讨sPD-1和4-1BBL联合治疗肿瘤的效应和相关的免疫学机制。方法以H22肝癌细胞接种于BALB／c小鼠右后腿肌肉内,建立小鼠肿瘤模型;采用4-1BBL和可溶性PD-1(sPD- 1)真核表达质粒通过肌肉转染进行基因治疗;检测小鼠肿瘤生长情况,并检测转染基因及肿瘤微环境中免疫调控相关基因的表达,检测肿瘤组织中的淋巴细胞数量的变化。结果单独转染4-1BBL基因或sPD-1基因均显示出抗肿瘤作用,而联合治疗对肿瘤生长抑制作用更为明显,该组抑瘤率高达92．3％(以pcDNA3．1组为对照),显著高于4-1BBL组(78％)、sPD-1组(70．2％)。联合治疗不仅使TGF-β、IL-10的表达下调,而且在治疗后期更有效地促进IFN-γ和IL-2基因表达上调,且使瘤组织中CD8+T淋巴细胞数量较其他各组显著增加。结论4-1BBL和sPD-1联合治疗可使肿瘤微环境中的免疫相关基因表达更有利于抗肿瘤免疫应答,增强肿瘤免疫治疗效果。更多还原

【Abstract】 Objective To investigate the synergistic effects of 4-1BBL in combination with sPD-1 in tumor treatment and the immunological mechanisms. Methods BALB/c mice were inoculated intramuscularly (i. m. ) with H22 tumor cells in the right hind thigh to establish the experimental hepatoma model. The eukaryotic expression plasmids of 4-1BBL and soluble PD-1 (sPD-1) were directly injected into the muscle for gene therapy. The weight of tumor was recorded. The expression of immunoregulatory genes in tumor microenvironment was detected. Results Both transfection with 4-1BBL gene alone or sPD-1 gene alone inhibited tumor growth to some extent, but the more significant therapeutic effect was only recored in the combinatorial treatment group, in which the tumor was conspicuously inhibited at the rate of 92.3%, as compared with 78% in 4-1BBL group and 70.2% in sPD-1 group. The combinatorial treatment resulted not only in the down-regulation of TGF-βand IL-10 genes, but also a much more significant up-regulation of IFN-γand IL-2 genes at the later phase of therapy. The amount of CD8+ T cells in tumor tissue of combinatorial treatment group was significantly increased, as compared with other groups. Conclusion The effect of immunotherapy on tumor can be augmented by the combination of 4-1BBL and sPD-1, which can improve the expression of the related immunoregulatory genes to establish a much better microenvironment in favor of antitumor immune response.更多还原