目的观察异体树突细胞(DCs)与骨肉瘤细胞融合瘤苗诱导的特异性抗骨肉瘤免疫学效应。方法采用Wistar大鼠骨髓来源的DCs与SD大鼠来源的骨肉瘤细胞UMR106,通过电穿孔的方法进行融合,制备异体融合瘤苗。经大鼠OX62单抗免疫磁珠分离纯化后,与SD大鼠骨髓来源的T淋巴细胞共同培养以刺激后者增殖。流式细胞仪检测CD8^+、CD4^+细胞比例,MTT法测定细胞毒T淋巴细胞(CTLs)的杀瘤活性。建立大鼠骨肉瘤动物模型,采用皮内注射的方式进行主动免疫治疗,观察荷瘤大鼠的存活率。结果与异体融合瘤苗共培养刺激后,T淋巴细胞增殖显著增强,CD8^+细胞比例由刺激前的34.2%升高到74.9%,CD4^+细胞比例由刺激前的59.2%降低到19.1%(P〈0.05)。该瘤苗诱导的UMR106特异性CTLs对肿瘤细胞的杀瘤活性显著增高。经该瘤苗主动免疫后,60%的荷瘤大鼠瘤体萎缩、消失,获得长期存活。结论异体树突细胞融合瘤苗可有效刺激T淋巴细胞增殖及诱导CTLs的杀瘤活性,具有良好的主动免疫治疗效应。
Objective To investigate the specific antitumor effects induced by allogeneic dendritic cells (DCs)/osteosarcoma cell fu- sion vaccine in rats. Methods Fusion vaccine of DCs derived from Wistar rat bone marrow and osteosarcoma cells (UMR106) derived from SD rat was generated by electroporation method, and purified by immunomagnetic beads coated with monoclonal antibody OX62, then cocuhured with T lymphocytes derived from SD bone marrow to stimulate the proliferation of the T lymphocytes. The proportion of CD8^+ and CD4^+ cells was determined by flow cytometry, and the anti-tumor activity of cytotoxic T lymphocytes (CTLs) was determined by MTT assay. The SD rat osteosarcoma model was established and active immunotherapy was performed through intradermal injection, and the survival rate of the model rats was observed. Results After cocuhured with allogeneic fusion vaccine, the proliferation of T cells increased significantly, and the proportion of CD8^+ cells increased from 34. 2% to 74. 9%, while of CD4^+ cells decreased from 59.2% to 19. 1% (P〈0. 05). The cytotoxicity of UMR106 specific CTLs induced by the fusion vaccine against the osteosarcoma cells was significantly enhanced. After active immunization of the fusion vaccine, the masses atrophied and vanished in 60% of tumor-bearing rats, and then the animals got long-term survival. Conclusions The allogeneic fusion vaccine can effectively stimulate the proliferation of T lymphocytes and induce the cytotoxicity of CTLs, and the active immunotherapeutic effect is satisfactory.