白细胞介素2质粒复合物治疗后小鼠肝癌的组织学变化

目的 探讨瘤体内直接注射白细胞介素2质粒／阳离子脂质体复合物治疗小鼠肝癌的效果和机制。方法 将小鼠白介素2表达质粒（VR1110）与阳离子脂质体（Transfectam)按适当比例混合而形成复合物（VR1110／Transfectam)。通过瘤体内接注射此复合物治疗小鼠肝癌模型，观察治疗后肿瘤积变化、组织学变化及表达情况。结果 瘤体内注射VR1110／Transfectam后，可在肿瘤组织中检测到小鼠IL－2mRNA的表达。VR1110／与Tansfectam治疗组肿瘤生长较其它对照组明显减慢，第1次治疗后第12天肿瘤体积明显小于其它组（P＜0．05）。治疗组小鼠均可见肿瘤组织大量坏死，炎性细胞浸润，及CD4^ 、CD8 淋巴细胞。结论 瘤体内直接注射VR1110／Transfectam复合物对小鼠肝癌的治疗作用明显，增强了小鼠机体对肝癌细胞的免疫学反应。

Histological Changes of Hepatoma Bearing Mice After Treatment with Intratumoral Injection of IL-2 Plasmid DNA/lipid Complexes

Objective To study the effect of interleukin 2 plasmid DNA/lipid complexes for the treatment of established hepatic tumors in mice by intratumoral injection.Methods DNA lipid complexes were formed by mixing eukaryotic expression plasmids VR1110 encoding the gene for mouse interleukin 2 with cationic lipids(Transfectam) at appropriate proportion.They were used to treat the established hepatic tumors in mice by intratumoral injection,followed by observing tumor volume,gene expression and histological appearance.Results The intratumoral injection of VR1110/Transfectam complexes resulted in the expression of mRNA,significant reduction in tumor volume 12 days after the first injection( P <0.05).At the mean time, serious necrosis and inflammatory cells infiltration(including CD 4 or CD 8 lymphocytes) were found in neoplastic tissues of all the mice treated with DNA/lipid complexes.ConclusionThe intratumoral injection of VR1110/Transfectam complexes can induce a significant antitumor response in hepatoma bearing mice and enhance immunologic response of mice to hepatoma cells.