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

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