转化缺陷的R6菌株经黏膜免疫小鼠可抵抗肺炎链球菌有毒株感染

发布时间：2018-06-11 16:41

本文选题：肺炎链球菌 + 黏膜免疫　；参考：《临床检验杂志》2013年04期

【摘要】：目的研制一种无转化能力的肺炎链球菌(S.pn)减毒株R6ΔcomE,评价其作为S.pn活菌疫苗的保护效果。方法构建comE基因缺陷的R6ΔcomE株,评价R6、R6ΔcomE株的转化能力及其毒力;用R6、R6ΔcomE株分别对BALB/c小鼠进行黏膜免疫,用ELISA法检测免疫小鼠血清特异性抗体效价和脾细胞上清中IFN-γ、IL-4及IL-17A水平;用D39株经鼻腔黏膜感染免疫小鼠,观察生存时间和生存率。结果成功构建comE缺陷的R6ΔcomE株。体外转化实验中R6株转化菌量中位数为1 970 CFU/mL,体内转化实验中每只小鼠34 CFU,体内外实验中R6ΔcomE株转化菌量均为0;感染1×108CFU D39株的小鼠于3 d内全部死亡,而感染相同剂量R6、R6ΔcomE株的小鼠均存活21 d,且均于感染后72 h内清除细菌。R6、R6ΔcomE株黏膜免疫小鼠后,血清抗体滴度的中位数(P25,P75)分别达1.0×106(6.4×105,1.8×106)、1.2×106(8.1×105,1.6×106),与相应阴性对照组比较差异有统计学意义(P均0.01);与相应阴性对照组比较,R6、R6ΔcomE株免疫组IL-4、IL-17A均升高(P均0.01),而IFN-γ水平差异无统计学意义(P0.05)。黏膜免疫R6、R6ΔcomE株的BALB/c小鼠可抵抗D39株感染,生存率分别为60%和70%。结论 R6ΔcomE株毒力弱,无转化能力,可诱导对S.pn感染的免疫保护,是一株安全有潜力的S.pn减毒活菌疫苗。
[Abstract]:Objective to develop a detoxification strain R6 螖 comE with no transformation ability, and to evaluate its protective effect as a live S.pn vaccine. Methods the R6 螖 comE strain was constructed, and the transformation ability and virulence of R6 R6 螖 comE strain were evaluated, the BALB / c mice were immunized with R6N R6 螖 comE strain, the specific antibody titers of serum and the levels of IFN- 纬 IL-4 and IL-17A in spleen cell supernatant of immunized mice were detected by Elisa. The survival time and survival rate of mice immunized with D39 strain of nasal mucosal infection were observed. Results the R6 螖 comE strain with comE deficiency was successfully constructed. In vitro transformation test, the median amount of R6 strain was 1 970 CFU / mL, in vivo transformation test was 34 CFU per mouse, and in vitro and in vivo test R6 螖 comE strain was 0. All the mice infected with 1 脳 108 CFU D39 strain died within 3 days. However, the mice infected with the same dose of R6, R6 螖 comE, survived for 21 days, and the mice were immunized with bacteria, R6, R6 螖 comE, within 72 hours after infection. The median titer of serum antibody was 1.0 脳 10 ~ (6) C ~ (6.4 脳 10 ~ (5) ~ (1.8) 脳 10 ~ (6) C ~ (-1) = 1.2 脳 10 ~ (6) C ~ (8.1) 脳 10 ~ (5) C ~ (1.6) 脳 10 ~ (6), there was significant difference between the two groups (P = 0.01), and compared with the corresponding negative control group, the IL-4 IL-17A of IL-4 and IL-17A were all increased (P = 0.01), but the level of IFN- 纬 was not significantly different from that of the corresponding negative control group (P < 0.05), but there was no significant difference in the level of IFN- 纬 between the two groups. BALB / c mice immunized with R6 / R6 螖 comE strain could resist D39 strain infection and the survival rate was 60% and 70%, respectively. Conclusion R6 螖 comE strain has weak virulence and no transformation ability, which can induce the immune protection against S.pn infection. It is a safe and potential vaccine against S.pn attenuated live bacteria.
【作者单位】：重庆医科大学检验医学院检验系临床检验诊断学实验室;
【基金】：国家自然科学基金(31070819) 重庆市渝中区科技计划项目(20110315) 重庆医科大学实验教学管理中心创新实验项目(201117)
【分类号】：R392

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