Analysis of the class-specific immune response to Yersinia enterocolitica virulence-associated antigens in oro-gastrically infected rabbits.
The antibody response was analysed in rabbits oro-gastrically infected (i) with virulent-(plasmid-carrying) Yersinia enterocolitica 0:3 (v-rabbits) and (ii) with the avirulent (plasmid-cured) derivative (av-rabbits). In an immunoblot assay with whole cell lysate proteins from the infecting virulent Yersinia strain, a significant IgG response was evident in convalescent-sera of v-rabbits and of av-rabbits, demonstrating that all rabbits seroconverted. However, v-rabbits mounted a stronger immune response to the cell lysate proteins than av-rabbits and the immune response persisted for a longer time. The post-challenge sera also reacted with whole cell lysate proteins of Escherichia coli and Salmonella typhimurium, indicating cross-reactivity between the different members of Enterobacteriaceae. In contrast, the antibody response against plasmid-encoded released proteins (RPs) appeared specific for infection with virulent strains in that the sera of av-rabbits failed to recognize the plasmid-encoded proteins. Six days following challenge with the virulent Yersinia strain all animals mounted a serum IgM and IgA response to RPs, followed by IgG antibodies on day 9. While the IgM and IgA serum antibody response rapidly decreased (within five-seven and eight-ten months, respectively), IgG antibodies to RPs were still present one year after challenge. Fourteen months after the first infection both the av-rabbits and the v-rabbits were reinfected with the virulent Yersinia strain and the antibody response to RPs was monitored. The v-rabbits only responded with a significant increase of IgG antibodies, indicating that they were primed to the RPs whereas the av-rabbits produced IgM, IgA and IgG specific antibodies like those seen in the primary response of v-rabbits. This study indicates that the rabbit model is helpful and adequate to analyse the character and kinetics of the antibody response during Yersinia infection.
Heesemann
J
J
Institute of Medical Microbiology and Immunology, University of Hamburg, F.R.G.
Schröder
J
J
Ulrich
M
M
D000372:Agglutination Tests; D000818:Animals; D000917:Antibody Formation; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins / Q000276:immunology*; D015151:Immunoblotting; D007074:Immunoglobulin G / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D007700:Kinetics; D010957:Plasmids; D011817:Rabbits; D012486:Salmonella typhimurium / Q000276:immunology; D015009:Yersinia Infections / Q000276:immunology*; D015008:Yersinia enterocolitica / Q000235:genetics / Q000276:immunology*
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D007074:Immunoglobulin G; D007075:Immunoglobulin M; C056187:Yop2b (Yersinia)