多糖佐剂FQ_2对日本血吸虫rBCG-Sj26GST疫苗增效作用及其机理的初步探讨

Studies on the efficacy of adjuvant FQ_2 on the enhancement of immunogenicity by rBCG-Sj26GST vaccine and its mechanism of action

为探讨多糖佐剂FQ2 对血吸虫疫苗保护性免疫力的增效作用及其机理 ,采用 1 0 8CFU日本血吸虫重组BCG -Sj2 6GST疫苗分别与 5 %、1 0 %、2 0 %浓度的佐剂FQ2 混匀皮下接种BALB/c小鼠 ,同时设对照组。接种后第 8W以日本血吸虫尾蚴攻击感染 ,感染后 6W剖杀小鼠 ,计算减虫率 ,测定血清中特异抗体水平和胸腺T淋巴细胞及其亚群。结果实验组获得了 33 49% - 4 0 50 %的减虫率 ,与对照组相比 ,胸腺细胞总数、胸腺活性细胞率、CD8+ 细胞率、CD4 + 细胞率均显著升高 ,尤其是疫苗 +1 0 %佐剂 ,疫苗 +2 0 %佐剂组差别有非常显著意义 (P <0 0 1 )。而各实验组IgG抗体水平无统计学差别。提示多糖佐剂FQ2 对日本血吸虫rBCG -Sj2 6GST疫苗有一定的增效作用 。

A adjuvant FQ 2 was tested for its potential to enhance the immunogenicity of recombinant BCG Sj26GST vaccine BALB/c mice were immunized subcutaneously with 10 8 CFU vaccine together with 5%FQ 2,10%FQ 2 and 20%FQ 2 respectively,and then challenged with Schistosoma japonica cercariae on the 8 th week after immunization and killed on the 6 th week of infection The rate of reduced worm burdens,the examination of the IgG level,and the measurement of the T lymphocyte amounts including the rate of active T cell and its subgroup CD + 4,CD + 8were performed later on Results showed that the rates of reduced worm burdens were 33 49%～40 50%,and the amount of T lymphocyte,the rates of active T cell,the number of CD + 4 and CD + 8 apparently increased There was remarkble difference between control mice and immunized ones But IgG was not detected during the 8 weeks after immunization And no significant differences among the IgG titres were observed after chanllenge This study indicates that adjuvant FQ 2 could promote the cellular immune response