CpG寡核苷酸增强鸡新城疫疫苗免疫效力的研究

为了探讨CpG寡核苷酸（CpG oligonucleotide,CpG ODN）对鸡新城疫疫苗免疫效力的影响,将CpG2007与鸡淋巴细胞共孵育,测定淋巴细胞增殖率,结果发现CpG2007对鸡淋巴细胞具有显著的刺激活性。将CpG2007与不同浓度的新城疫抗原混合,制备灭活疫苗,免疫健康雏鸡。分别于免疫后不同时间采血,测定抗体效价和细胞因子表达量,并进行攻毒保护试验。结果发现,添加CpG ODN佐剂的试验组均比对应相同抗原剂量的免疫对照组的抗体水平高,产生抗体速度快;抗原剂量降低10倍的佐剂试验组与高抗原剂量免疫对照组抗体水平和攻毒保护率均相当,表明CpG ODN能显著增强新城疫疫苗的免疫效力,能促进机体产生更强烈的免疫应答,是有效的疫苗佐剂候选物质。

ENHANCEMENT OF CPG ODN ON IMMUNE RESPONSES OF INACTIVATED NEWCASTLE DISEASE VIRUS VACCINE

The immune enhancement of the unmethylated CpG oligonucleotides（CpG ODNs） on inactivated Newcastle disease virus（NDV） vaccine was investigated in chickens.In the lymphocyte proliferation assay,CpG ODN2007 induced a significant stimulatory effect on cell proliferation even at low concentrations.Subsequently,chickens were immunized with different doses of inactivated NDV supplemented with CpG ODN2007.Blood samples were collected to measure antibody titers and cell mediated immune response.Then,chickens were challenged with virulent NDV.As a result,chickens immunized with NDV plus CpG ODN2007 showed a significantly enhanced antibody response in comparison with the control group that received equal doses of NDV alone.The antibody titers and protection against virulent virus challenge in the chickens immunized with 1/10 dose of NDV plus CpG ODN2007 were comparable with those immunized with the highest dose of NDV alone.The present study demonstrated the immune enhancement of CpG ODN on immune responses of inactivated NDV vaccine in chickens.