Effect Of Different Adjuvants On S.Aureus CP8-FnBPB-CIFA Multivalent Virulence Factor Vaccine

Bovine mastitis is a reflection of inflammation on breast tissue that stimulated by the external factors. The mammary gland suffers pathological injures as the result of being infected by bovine mastitis, which also increases the somatic cell counts and compromises the quality and quantity of milk. Because the pathogenic microorganisms are the principal factors as the reason for the leading to bovine mastitis, the aim of this paper is about Staphylococcus aureus bovine mastitis based on the previous researches in our lab on self-constructed CP8-FnBPB-ClfA subunit antibiotic of Staphylococcus aureus of bovine mastitis and filtrating the more efficient adjuvant and immune method from rabbit bovine mastitis model.1. On the basis of the previous researches,1.7970g CP8have been get from S. aureus which had been identified of serum type8. Expressed the plasmid containing fusion protein FnBPB-ClfA in Escherichia coli and coupled with CP8. The conjugates named CP8-FnBPB-ClfA.2. Using the indirect ELISA and Western blot to evaluated humoral immune effects and monitored serum antibodies of each group of New Zealand white rabbits at different times after immunization. The rabbits were immunized by CP8-FnBPB-ClfA coordinate with Freund’s adjuvant, aluminum hydroxide (ALUM) adjuvant, liposome adjuvant and Escherichia coli heat-labile enterotoxin B (LTB) adjuvant respectively. The paper evaluated the effect of cellular immunity by detecting Th1/Th2cytokine level and T lymphocyte proliferation test. Antibody test results showed that the first group started generating antibodies was the test group with liposome as adjuvant, at7th. But after14d, the antibody levels began to decline. The highest antibody levels in the experimental group was the group was keep the longest time with LTB as adjuvant. Thl/Th2cytokines level test results showed varying degrees of improvement for each test group, as an adjuvant to Freund’s or liposome, the immunization of ALUM or LTB is better, but the test group with ALUM and LTB has little difference. The immune adjuvant not only can improve the level of immune cells, but also enhanced humoral immunity. The results of T lymphocyte proliferation test showed that T lymphocytes was general proliferation and no significant difference in each group after stimulated by ConA, which stimulation index is about1.0. In the groups stimulated by antigen, the strongest T lymphocyte proliferation group is with LTB as adjuvant, stimulation index was2.23. Screening the best immunization and to challenge test. The challenge test results showed that homemade vaccine protection rate is80%.3. Immunized animals by conjugates CP8-FnBPB-ClfA with ALUM as adjuvant. Compared the immunized group with the control group, the somatic cell count dropped to the normal range or maintained in the normal range, the number of somatic cells in the control group increased beyond the normal range or unchanged in the non-normal range. The result of separating and identifying the bacterium in the milk showed that the numbers of S.aureus decreased with the immune days in the immunized group and the S.aureus increased in the control. The result of ELISA showed that the antibody levels of serum and milk in immunized group were significant differences with the control (p<0.05).