应用包裹在纳米粒中的CpG脱氧寡核苷酸增强对乙肝疫苗的免疫应答

The enhanced immune responses induced by chitosan-CpG ODN nanoparticles with hepatitis B vaccine on mice

目的:探讨应用包裹在壳聚糖纳米粒中的胞嘧啶-鸟嘌呤的脱氧寡核苷酸(CpG ODN)增强小鼠对乙肝疫苗的免疫应答。方法:采用复凝聚方法制备CpG ODN壳聚糖纳米粒。乙肝疫苗单用或联合CpG ODN免疫小鼠,用ELISA法检测抗HBs水平,流式细胞仪检测外周血CD4+、CD8+T淋巴细胞亚群,MTT法检测脾淋巴细胞增殖活性。结果:CpG ODN联合乙肝疫苗组抗HBs水平较单用乙肝疫苗组明显升高,且以CpG ODN壳聚糖纳米粒联合组产生的抗HBs水平最高;T淋巴细胞亚群分析显示,CpG ODN纳米粒联合组的CD4+T淋巴细胞百分比和CD4+/CD8+比值明显高于单用乙肝疫苗组;CpG ODN纳米粒联合组的脾淋巴细胞刺激指数明显高于其他组。结论:CpG ODN壳聚糖纳米粒联合乙肝疫苗不仅能诱导出高水平的抗HBs,且对细胞免疫也有调节作用。

OBJECTIVE To investigate the effects of CpG ODN prepared by chitosan nanoparticles on immune response in BALB/c mice with hepatitis B vaccine. METHODS Chitosan-CpG ODN nanoparticles were prepared by complex coacervation method. The same doses of hepatitis B vaccine with or without CpG ODiN were injected into immune mice The serum anti-HBs levels in mice were detected by ELISA assays in three weeks after the second injection. Changes of peripheral blood T lymphocyte subsets CD4^＋ ,CD8^＋ were detected by flow cytometry. Proliferation of the spleen cells were detected by MTT. RESULTS The serum anti-HBs levels in mice injected by CpG ODN combining with hepatitis B vaccine were higher than that of the mice only injected by hepatitis B vaccine. Compared with the immunization with HBsAg plus CpG ODN, the immunization with HB- sAg plus CpG ODN nanoparticles had a significant increase in anti-HBs levels. Percentages of CD4^＋ and CD4^＋/CD8^＋ ratio of mice immunized with hepatitis B vaccine plus CpG ODN nanoparticles increased more than that only with hepatitis B vaccine. In addition,the spleen cells obtained from mice immunized with CpG ODN nanoparticles showed higher specific proliferative response. CONCLUSION Chitosan-CpG ODN nanoparticles combining with hepatitis B vaccine not only induce the high level of anti-HBs, but also can enhance the cellular immune response in mice.