紫外灭活CVB3 病毒诱导BALB/c小鼠产生免疫保护作用的研究

目的:探讨紫外灭活型CVB3病毒诱导BALB/c小鼠产生特异性免疫应答及保护作用的评估。方法:采用紫外灭活的方法处理野生型CVB3m株,按照0.1 LD50(10~4 PFU)的剂量免疫小鼠,设置PBS免疫组作为对照,免疫后第3,5,7天收集小鼠血清,检测细胞因子含量;在第3,5,7,14天分离小鼠脾脏,流式分析T细胞亚群的分布比例;在免疫后一个月分离小鼠血清,检测中和抗体的滴度;同时间给予小鼠100LD 50野生型CVB3感染,观察小鼠的死亡率。结果:与对照组相比,在检测日期内紫外灭活型CVB3组小鼠血清中细胞因子IL-1α,TNF-α,IL-6的表达量明显增高(P0.05),IL-4的表达量没有明显差异;免疫后第14天CD3~+CD4~+T细胞的分布较对照组明显升高(P0.05);在免疫后一个月,紫外灭活型CVB3免疫组可以诱导机体产生高滴度中和抗体,同时,小鼠应对高致死量CVB3感染时有较高的存活率。结论:紫外灭活型CVB3感染能诱导机体产生特异性免疫应答,同时,产生的中和抗体可以提高小鼠应对致死剂量CVB3感染时的生存率,对机体有明显的保护作用。

Study of Protective Immune Effect Induced by UV-inactivated CVB3 on the BALB/c Mice

Objective:To investigate specific immune response and protective effect of BALB/c mice induced by UV inactivated CVB3.Methods:Wild CVB3 mstrain was inactivated by UV, and male BALB/c mice were immunized with 0.1 LD50 (104 PFU) of UV inactivated CVB3, named CVB3-UV, PBS treated mice were set as compared group. On the 3, 5, 7 days post immunization mice were sacrificed, serum were collected and cytokines were detected by CBA method, T cell subset were analyzed by flow cytometry method in the splenocytes on the 3, 5, 7, 14 days post immunization, neutralizing antibody in the sera of immunized mice 1 month later were detected, further, mice survival rate were also evaluated after challenge with lethal dose of wild type CVB3.Results:Compared with PBS treated group, CVB3-UV could induce high levels of IL-1alpha, TNF-alpha and IL-6 (P<0.05), while IL-4 production was comparable between both groups. CD3+CD4+T cell development were found affected on the 14 days post immunization by CVB3-UV (P<0.05), and higher titer neutralizing antibody were induced in the CVB3-UV treated mice. Importantly, higher survival rate of mice were found in the CVB3-UV group after re-infection by lethal CVB3.Conclusion:UV-inactivated CVB3 could induce specific immune response and support obvious protective effect in BALB/c mice.