title: 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.
abstract: 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 microg/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 microg/ml and to mice less than 100 microg/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.
authors.affiliation: Faculty of Animal Science and Veterinary Medicine, Guizhou University, Xueshi Road, Guiyang, Guizhou Province, China.
authors.forename: Xue Qin
authors.initials: XQ
authors.lastname: Ran
authors.forename: Hong Zhen
authors.initials: HZ
authors.lastname: Wang
authors.forename: Jin Juan
authors.initials: JJ
authors.lastname: Liu
authors.forename: Sheng
authors.initials: S
authors.lastname: Li
authors.forename: Jia Fu
authors.initials: JF
authors.lastname: Wang
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood / Q000378:metabolism; D001427:Bacterial Toxins / Q000235:genetics / Q000276:immunology*; D001428:Bacterial Vaccines / Q000276:immunology*; D002522:Chlorocebus aethiops; D003001:Cloning, Molecular; D004768:Enterotoxins / Q000235:genetics / Q000276:immunology*; D004926:Escherichia coli / Q000276:immunology; D004927:Escherichia coli Infections / Q000517:prevention & control*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000276:immunology*; D051379:Mice; D011817:Rabbits; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology* / Q000633:toxicity; D022641:Shiga Toxin 2 / Q000235:genetics / Q000276:immunology*; D016019:Survival Analysis; D013552:Swine; D013553:Swine Diseases / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control; D014614:Vaccines, Synthetic / Q000276:immunology; D014709:Vero Cells
chemical_list: D000907:Antibodies, Bacterial; D001427:Bacterial Toxins; D001428:Bacterial Vaccines; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D011993:Recombinant Fusion Proteins; D022641:Shiga Toxin 2; D014614:Vaccines, Synthetic; C450841:shiga toxin 2 B subunit; C027538:heat-labile enterotoxin, E coli