Characterization of antiserum after co-immunized with adhesins expressing Clf A,Fn BPA-A and Fn BPA-BCD of Staphylococus aureus
[Objective] To compare the antigenicity，adhesion inhibition activity and immune protection of the serum immunized with recombinant adhesins Clumping factor A( Clf A)，Fibronection binding protein A-A( Fn BPA-A) and Fibronection binding protein A-BCD( Fn BPA-BCD) of Staphylococcus aureus. [Methods] Clf A，Fn BPA-A and Fn BPABCD genes were expressed and the resulting recombinant proteins were induced and purified. After immunizing mice with these purified proteins in combination or alone，the serum antibodies of mice were analyzed and compared for their antigenicity，adhesion inhibition activity and immune protection. [Results] The recombinant Fn BPA-BCD protein had better fibronection( Fn) binding ability than that of fibrinogen( Fg) binding and Clf A. Fn BPA-A had better binding capacity to Fg than that of Fn BPA-BCD. The antibody titer induced by Clf A and Fn BPA-A were better than that of Fn BPA-BCD，and three proteins co-immunization group had better antibody titer and adhesion inhibition to Staphylococcus aureus than those of single recombinant protein immunization group( P0. 05). The immune protection rate for both Clf A and three proteins co-immunization group were 100% and for Fn BPA-A and Fn BPA-BCD immunization group the immune protection rate were 80% and 50%，respectively. [Conclusion] Our data suggest that coimmunization with these 3recombinant proteins helps to achieve better immune effect.