title: Immunization with H7-HCP-tir-intimin significantly reduces colonization and shedding of Escherichia coli O157:H7 in goats.
abstract: Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is the causative agent of hemorrhagic colitis and hemolytic uremic syndrome in humans. However, the bacterium can colonize the intestines of ruminants without causing clinical signs. EHEC O157:H7 needs flagella (H7) and hemorrhagic coli pili (HCP) to adhere to epithelial cells. Then the bacterium uses the translocated intimin receptor (Tir) and an outer membrane adhesion (Intimin) protein to colonize hosts. This leads to the attachment and effacement of (A/E) lesions. A tetravalent recombinant vaccine (H7-HCP-Tir-Intimin) composed of immunologically important portions of H7, HCP, Tir and Intimin proteins was constructed and its efficacy was evaluated using a caprine model. The results showed that the recombinant vaccine induced strong humoral and mucosal immune responses and protected the subjects from live challenges with EHEC O157:H7 86-24 stain. After a second immunization, the average IgG titer peaked at 7.2 × 10(5). Five days after challenge, E. coli O157:H7 was no longer detectable in the feces of vaccinated goats, but naïve goats shed the bacterium throughout the course of the challenge. Cultures of intestinal tissues showed that vaccination of goats with H7-HCP-Tir-Intimin reduced the amount of intestinal colonization by EHEC O157:H7 effectively. Recombinant H7-HCP-Tir-Intimin protein is an excellent vaccine candidate. Data from the present study warrant further efficacy studies aimed at reducing EHEC O157:H7 load on farms and the contamination of carcasses by this zoonotic pathogen.
authors.affiliation: Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, P. R. China; Key Laboratory of Engineering Research of Veterinary Bio-products of Agricultural Ministry, Nanjing, P. R. China; National Center for Engineering Research of Veterinary Bio-products, Nanjing, P. R. China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, P. R. China.
authors.forename: Xuehan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, P. R. China; Key Laboratory of Engineering Research of Veterinary Bio-products of Agricultural Ministry, Nanjing, P. R. China; National Center for Engineering Research of Veterinary Bio-products, Nanjing, P. R. China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, P. R. China.
authors.forename: Zhengyu
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States of America.
authors.forename: Shuping
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, P. R. China; Key Laboratory of Engineering Research of Veterinary Bio-products of Agricultural Ministry, Nanjing, P. R. China; National Center for Engineering Research of Veterinary Bio-products, Nanjing, P. R. China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, P. R. China.
authors.forename: Kongwang
authors.initials: K
authors.lastname: He
mesh_terms: D018829:Adhesins, Bacterial; D000820:Animal Diseases / Q000276:immunology* / Q000382:microbiology*; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood / Q000276:immunology; D000918:Antibody Specificity / Q000276:immunology; D057138:Bacterial Shedding / Q000276:immunology; D004927:Escherichia coli Infections / Q000662:veterinary*; D019453:Escherichia coli O157 / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism; D022361:Escherichia coli Vaccines / Q000008:administration & dosage / Q000276:immunology*; D023061:Gene Order; D006041:Goats / Q000276:immunology* / Q000382:microbiology*; D007114:Immunization; D007070:Immunoglobulin A / Q000097:blood / Q000276:immunology; D008297:Male; D010957:Plasmids / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000276:immunology
chemical_list: D018829:Adhesins, Bacterial; D000907:Antibodies, Bacterial; D029968:Escherichia coli Proteins; D022361:Escherichia coli Vaccines; D007070:Immunoglobulin A; D011993:Recombinant Fusion Proteins; D014614:Vaccines, Synthetic