摘要
为了研究白细胞介素-18(IL-18)基因对人免疫缺陷病毒(HIV-1)核酸疫苗诱导免疫应答的影响,将人IL-18基因插入到真核表达载体pVAX1中,构建了真核表达载体pVAX1-IL-18;将pCI-neoGAG联合pVAX1-IL-18或者pCI-neoGAG单独免疫Balb/c小鼠,检测免疫小鼠的特异性抗体和IFN-γ,同时观察免疫小鼠脾淋巴细胞增殖和小鼠特异性细胞毒性T淋巴细胞(CTL)反应。酶切及测序结果表明成功地构建了人IL-18基因真核表达载体;与pCI-neoGAG免疫组比较,pCI-neoGAG联合pVAX1-IL-18免疫组小鼠血清的抗HIV-1p24抗体滴度降低(P<0.01);而与pCI-neoGAG免疫组比较,pCI-neoGAG联合pVAX1-IL-18免疫组小鼠血清的IFN-γ升高(P<0.01);pCI-neoGAG联合pVAX1-IL-18免疫组小鼠的脾淋巴细胞增殖实验刺激指数(SI)以及特异性CTL活性均高于pCI-neoGAG免疫组(P<0.01)。IL-18基因联合HIV-1核酸疫苗免疫小鼠,可能增强特异性Th1细胞和CTL反应,白细胞介素-18基因对体液免疫有抑制作用。
To investigate the effect of interleukin-18 (IL-18) DNA immunization on immune response induced by Human immunodeficiency virus 1(HIV-1) nucleic acid vaccine (DNA vaccine), the recombinant expression vector pVAX1-IL-18 was constructed by inserting the IL-18 gene into the eukaryotic expression vector pVAX1. Balb/c mice were immunized with pCI-neoGAG alone or co-administered with the DNA encoding for IL-18. Their sera were collected for analyzing anti-HIV antibody and IFN-?by ELISA, and spleen cells were isolated for detecting antigen-specific lymphoproliferative responses and specific CTL response by MTT assay and LDH assay, respectively. Restriction enzymes digestion analysis and DNA sequencing results revealed that the recombinant expression vector pVAX1-IL-18 has been constructed successfully. The anti-HIV antibody titers of mice co-immunized with pCI-neoGAG and the DNA encoding for IL-18 were lower than that of mice immunized with pCI-neoGAG alone (P<0.01). In contrast, the IFN- level of mice co-immunized with pCI-neoGAG and the DNA encoding for IL-18 was higher than that of mice immunized with pCI-neoGAG alone (P<0.01). Furthermore, compared with mice injected with pCI- neoGAG alone, the specific CTL cytotoxity and antigen-specific lymphoproliferative responses of mice immunized with pCI-neoGAG and the DNA encoding for IL-18 were significantly enhanced (P<0.01). The DNA encoding for IL-18 together with HIV DNA vaccine may enhance specific Th-1 responses and cellular immune responses elicited in mice. However, the DNA encoding for IL-18 may down-regulate the humoral responses.
出处
《中国病毒学》
CSCD
2004年第2期97-100,共4页
Virologica Sinica
