The immunogenicity of fusion protein linking the carboxyl terminus of the B subunit of Shiga toxin 2 to the B subunit of E. coli heat-labile enterotoxin

• Published in: Veterinary microbiology 2008-02, Vol.127 (1), p.209-215
• Main Authors: Ran, Xue Qin, Wang, Hong Zhen, Liu, Jin Juan, Li, Sheng, Wang, Jia Fu
• Format: Article
• Language: English
• Subjects: Animals; Antibodies, Bacterial - blood; Antibodies, Bacterial - metabolism; bacterial antigens; bacterial proteins; Bacterial Toxins - genetics; Bacterial Toxins - immunology; Bacterial Vaccines - immunology; Bacteriology; Biological and medical sciences; Chlorocebus aethiops; Cloning, Molecular; conjugation; diarrhea; disease control; edema; enterotoxins; Enterotoxins - genetics; Enterotoxins - immunology; Escherichia coli - immunology; Escherichia coli Infections - prevention & control; Escherichia coli Proteins - genetics; Escherichia coli Proteins - immunology; Escherichia infections; Fundamental and applied biological sciences. Psychology; Fusion protein; immune response; Immunogenicity; in vitro studies; in vivo studies; ltB gene; Mice; Microbiology; Pathogenicity, virulence, toxins, bacteriocins, pyrogens, host-bacteria relations, miscellaneous strains; Piglet; piglets; protective effect; Rabbits; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - immunology; Recombinant Fusion Proteins - toxicity; Shiga Toxin 2 - genetics; Shiga Toxin 2 - immunology; Shiga-like toxins; Stx2e gene; subunit vaccines; Survival Analysis; Swine; swine diseases; Swine Diseases - immunology; Swine Diseases - microbiology; Swine Diseases - prevention & control; vaccination; vaccine adjuvants; vaccine development; Vaccines, Synthetic - immunology; Vero Cells
• ISSN: 0378-1135; 1873-2542
• DOI: 10.1016/j.vetmic.2007.08.021

To augment the immunogenicity of the subunit B of Shiga toxin (Stx2e B) produced by Escherichia coli and protect piglets from edema disease in china, a fusion gene was constructed consisting of Stx2e B genetically linked at the N-terminus of the B subunit of heat-labile enterotoxin (LTB) in a translational fusion. After being induced with IPTG, the expressed fusion protein of Stx2e B-LTB was about 8.8% of total proteins, approximately 13 μg/ml of the bacteria culture. The Stx2e B-LTB fusion protein was found to be nontoxic to Vero cells at the dose higher than 1 μg/ml and to mice less than 100 μg/ml. Antibody titer against the fusion protein Stx2e B-LTB was 1:76,800, much higher than that of the recombinant Stx2e B protein (1:12,800) alone. All of the mice immunized with the Stx2e B-LTB fusion protein survived when challenged with a lethal dose (LD) of Stx2e toxin. The results showed that the poor immunogenicity of Stx2e B was overcome by conjugating the stx2e B to ltB. The immunogenicity of the constructed fusion protein Stx2e B-LTB in the present study was highly qualified to protect animals against Shiga toxin produced from Shiga toxin-producing Escherichia coli (STEC). The fusion protein of Stx2e B-LTB could be a candidate for a vaccine against edema disease and post-weaning diarrhea simultaneously in piglets.