Figure 4.

The ability of r0375 to block the union of antigen-antibody and deposition of C1q mediated by IgG. (A) Interaction of anti-rPVPA polyclonal serum and its antigen rPVPA was evaluated after pre-incubation of serum with r0375. Anti-rPVPA polyclonal serum combines with rPVPA as a control. (B) Interaction of anti-M. bovis polyclonal serum and the whole bacterial proteins of M. bovis strain PD was evaluated as in (A). (C) Interaction of anti-M. bovis polyclonal serum and rP48 was evaluated as in (A). Error bars correspond to the SD of three technical replicates. (D) Western blotting detects that r0375 inhibit the deposition of IgG and C1q on the bacterial surface. Mycoplasma bovis incubated with PBS in HNS or in absence of HNS as controls. The other two groups are M. bovis incubated with its polyclonal serum or its polyclonal serum that pre-incubated with r0375. The amount of IgG and C1q on the surface of M. bovis was detected, and P48 was used to reflect the number of bacteria. (E) Graph showing the ratio of the protein amount in IgG or C1q fraction to the protein amount in p48 fraction. The asterisk above the charts stands for statistically significant differences. **P ≤ 0.01.