Levels of expression and immunogenicity of attenuated Salmonella enterica serovar typhimurium strains expressing Escherichia coli mutant heat-labile enterotoxin.

ABSTRACT: The effects of heterologous gene dosage as well as Salmonella typhimurium strain variability on immune response toward both the heterologous antigen, the nontoxic mutant of the Escherichia coli heat-labile enterotoxin LTK63, and the carrier Salmonella strain have been analyzed. Effects of a single integration into the host DNA and different-copy-number episomal vectors were compared in S. typhimurium delta cya delta crp delta asd strains of two different serotypes, UK-1 and SR-11. Expression of the enterotoxin in the different Salmonella isolates in vitro was found to vary considerably and, for the episomal vectors, to correlate with the plasmid copy number. LTK63-specific serum immunoglobulin G (IgG) and mucosal immunoglobulin A (IgA) antibodies were highest in mice immunized with the hig

SUBMITTER: Covone MG 

PROVIDER: S-EPMC107881 | biostudies-literature | 1998 Jan

REPOSITORIES: biostudies-literature