Comparison of immunogenicity between recombinant flagellins C and B of Salmonella abortus equi
【Abstract】To evaluate and compare the immunogenicity differences of flagellins FliC and FljB of Salmonella abortus equi, and lay the experimental foundation for the further utilization of the two recombinant proteins, FliC and FljB recombinant proteins were induced, expressed and purified. The purified FliC and FljB were used to immunize mice separately. The antibody level, titer, and subtype of mice serum were detected after immunization. Immune-related receptors and histopathological changes were observed in immunized mice after challenged. The recombinant proteins FliC and FljB were successfully induced and expressed. Proteins of about 52 kDa and 42 kDa were purified. High levels of specific IgG antibodies were induced in mice immunized with these two proteins, the antibody level of FljB-immunized group was higher than that of the FliC-immunized group, and IgG1 was the dominant subtype of antibody. The challenge protection rate of the FljB-immunized group was 87.5%, which was higher than that of the FliC-immunized group (75%). Bacterial loads and pathological changes of FljB-immunized group were better than that of the FliC-immunized group, and the levels of TCR2, TCR4, MHC-I, and TCR induced by the FljB-immunized group were higher than those of the FliC-immunized group. The immune response induced by the FljB-immunized group was better than that of the FliC-immunized group.
【Keywords】 Salmonella abortus equi; flagellin C; flagellin B; immunogenicity;
(Translated by XU XY)
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