糖基磷脂酰肌醇锚定型小鼠B7.1融合蛋白的制备及抗肿瘤作用研究

Preparation of mB7.1-GPI-anchored tumor vaccine and its antitumor effect

目的制备糖基磷脂酰肌醇锚定型小鼠B7.1融合蛋白(mB7.1GPI),研究该蛋白制备的肿瘤疫苗的抗肿瘤作用。方法用已构建的重组糖基磷脂酰肌醇锚定型小鼠B7.1的表达载体pcDNA3.1(+)mB7.1GPI,转染到CHO细胞中,表达和纯化mB7.1GPI。采用流式细胞术和免疫荧光激光共聚焦显微镜观察其对细胞膜的锚定作用。建立C57BL6小鼠的淋巴瘤模型,观察用mB7.1GPI融合蛋白制备的肿瘤疫苗对荷瘤小鼠的免疫治疗作用。结果mB7.1GPI融合蛋白能够锚定在肿瘤细胞膜上,能有效刺激小鼠脾细胞增殖和分泌IL2与IFNγ。融合蛋白制备的肿瘤疫苗能够显著抑制荷瘤小鼠肿瘤的生长,并延长其生存期。结论糖基磷脂酰肌醇锚定型小鼠B7.1制备的肿瘤疫苗具有较强的抗肿瘤作用,有可能作为一种有效的新型疫苗用于肿瘤的治疗和预防。

Objective To prepare the mB7.1-GPI-anchored EL-4 vaccine and to identify its antitumor effects. Methods To construct mB7.1-GPI fusion gene, and express mB7.1-GPI fusion protein and then incorporate it into EL-4 tumor cells for preparing mB7.1-GPI-anchoring tumor vaccine. Results mB7.1-GPI fusion protein was stably anchored onto the surface of EL-4 tumor cells, and the surface protein showed its biological activities by stimulating lymphocyte proliferation and inducing lymphocytes to release IL-2 and IFN-γ in vitro. The tumor cell vaccine prepared from EL-4 cells coated with mB7.1-GPI exhibited antitumor effect. Conclusion The tumor vaccine prepared with mB7.1-GPI fusion protein significantly inhibited tumor growth in lymphoma bearing mice. It represents a new strategy for attaching immunological factor onto tumor cell surfaces without genetic manipulation.