将呼吸道合胞病毒(respiratory syncytical virus,RSV)G蛋白与CpG佐剂共同免疫小鼠,分析RSV G蛋白免疫原性及安全性。前期纯化的G_(CX3C)和G_(CTL)两种蛋白分别与CpG佐剂混合,在0、2、4周以肌肉注射方式免疫昆明小鼠,免疫结束后检测小鼠肺部匀浆液中的IFN-γ、IL-4及Ig E等指标。同时末次免疫结束后,小鼠用滴度105pfu的RSV进行攻毒,解剖分离小鼠肺部,制备病理切片进行观察。G_(CTL)蛋白免疫组肺部匀浆液中的IL-4以及IgE低于G_(CX3C)蛋白免疫组。CpG组及GCTL+CpG组肺组织匀浆液中的INF-γ含量以及INF-γ/IL-4比值显著高于其他组(P〈0.05),且ELISPOT实验表明CpG佐剂能够促使分泌INF-γ的脾淋巴细胞数量增多。攻毒后,通过肺部组织切片观察,发现PBS和CpG免疫组肺部病变极为严重,G_(CTL)+CpG组的病变程度比G_(CX3C)+CpG组严重,而G_(CX3C)组的病变情况比G_(CTL)组严重。这些结果表明,重组G_(CTL)蛋白能够降低动物免疫应答的Th2型极化,具有良好的安全性。
To evaluate the immune safety of recombinant G protein of respiratory syncyfial virus (RSV), pu- rified Gcrec and GCTL proteins were immunized mice with CpG adjuvant by intramuscular injection on 0, 2 and 4 weeks. After immunization, IFN-T,IL-4 and IgE in mouse lung were detected. 105 pfu RSV was used to challenge the immunized mice. The lungs of challenged mice were performed histologic section for pathologi- cal test. IL-4 and IgE in the lung of the Gcngroup were lower than that of the Gcx3c group. INF-T content and INF-T/IL-4 ratio of the CpG group and the GCTL+CpG group were significantly higher (P〈0.05) than that of other groups. And ELISPOT experiments showed that the CpG adjuvant could increase the number of spleen lymphocytes secreting INF-T. After virus challenged mice, the lung lesions of PBS group and CpG group were observed and extremely severe. The histological lesion in GCTL+CpG group was more severe than that in Gcx3c+CpG group. However, the tissue lesion in GcrL group was much better than that in Gcx3c group. The experimental results showed that the recombinant GcrL protein can reduce the Th2 type immune response with good safety and protection against the wild-type RSV challenge.