化疗后淋巴细胞减少期肿瘤疫苗免疫治疗卵巢上皮性癌的动物实验研究

目的 探索化疗后淋巴细胞减少期行免疫重建及应用GM-CSF基因修饰的卵巢上皮性癌(卵巢癌)肿瘤疫苗过继免疫治疗方案增强抗肿瘤免疫反应的机制及效果.方法 以环磷酰胺化疗引起大鼠淋巴细胞减少,并建立免疫重建大鼠模型,用活肿瘤疫苗GM-CSF/NUTU-19免疫大鼠模型,收集肿瘤疫苗免疫部位引流淋巴结,制备效应T淋巴细胞(T_E),酶联免疫吸附试验测定T_E分泌IL(白细胞介素)2、IL-4的能力,细胞内细胞因子染色法测定肿瘤特异性T_E的频数,流式细胞仪测定T_E对靶细胞的特异性细胞毒杀伤率.并将T_E过继回输给腹腔荷卵巢癌的大鼠,观察其生存期.结果 化疗-免疫重建-肿瘤疫苗免疫大鼠T_E分泌的IL-2水平增高,为(65.7±4.0)pg/ml,IL-d.分泌水平降低,为(277±49)pg/ml;细胞内细胞因子染色法结果提示,能分泌干扰素γ的CD_4~+;T淋巴细胞频数增高,为(13.0±2.1)%;T_E对靶细胞的杀伤率提高,为(86.5±1.1)%;经化疗-免疫重建-肿瘤疫苗免疫大鼠T_E过继免疫治疗的荷瘤大鼠生存期延长,平均生存时间为(110±16)d.结论 化疗-免疫重建-肿瘤疫苗免疫治疗能使肿瘤特异性T_E频数增加、功能增强,提高肿瘤特异性杀伤能力,有助于改善肿瘤特异性T_E细胞对肿瘤抗原弱刺激的反应性,增强抗肿瘤免疫反应.

Animal experiments of immunotherapy with ovarian tumor vaccine during lymphopenia induced by chemotherapy

Objective To explore the mechanisms and effects of adoptive immunotherapy with ovarian cancer vaccine modified by GM-CSF gene which was used after immunologic reconstitution during lymphopenia induced by chemotherapy.Methods Lymphopenia was induced by chemotherapy with cyclophosphamide.The immune reconstituted model was built in rats.The tumor vaccine draining lymph nodes were harvested after the ovarian cancer cells NUTU-19 modified by GM-CSF gene were injected.The effector T cells (T_E) were got after being stimulated and amplified.Enzyme-linked immunosorbent assay was used to detect the level of interleukin (IL)-2 and IL-4 secreted by T_E.Intracellular cytokine staining was used to determine frequency of tumor-specific T_E.Fluorescence-activated cell sorting (FACS) was used to detect the special cytotoxicity ofT_E killing target cells.The survival period of rats bearing pre-established abdominal ovariam carcinoma after being adoptively transferred byT_E.was observed.Results Compared with those in control group,the significant higher levels IL-2(65.7±4.0) pg/ml]and lower levels IL-4 (277±49) pg/ml]were observed in chemotherapy-immune recunstitution-vaccine immunization group.The amount of CD_4~+ T cells secreting interferon-γ (13.0±2.1)% were also significantly increased.The rate of the special cytotoxicity of killing T cells (86.5±1.1) % was markedly improved.The survival period of rats (110±16) days was increased in chemotherapy-immune reconstitution-vaccine immunization group.Conclusions The combined immunotherapy of chemotherapy-immune reconstitution-tumor vaccine immunotherapy may increase the frequency and function of specific tumor T_E.The specific cytotoxicity is increased and the weak reaction of T_E to tumor is improved,which showed that this therapy can enhance immune reaction.