title: Design and characterization of highly immunogenic heat-stable enterotoxin of enterotoxigenic Escherichia coli K99(+).
abstract: In this study, STa peptide of enterotoxigenic Escherichia coli K99(+) was purified and successfully covalently cross-linked to modified bovine serum albumin after thorough evaluation of three different hapten-carrier conjugation protocols. Dimethyformamide (DMF) based STa-conjugation protocol demonstrated higher biological activity (10×10(6) STa Total Mouse Units [MU]) and 100% conjugation efficiency. A range of conjugation ratio of 4-12 STa molecules per one molecule of BSA was achieved and confirmed by matrix-assisted laser desorption ionization-time of flight/mass spectroscopy (MALDI-TOF/MS). This conjugate was used for immunization of ten rabbits for STa antibody production. A high antibody binding titer (10(6)) against STa was obtained with a neutralization capacity of 3×10(4) STa MUs/ml serum. These levels of high STa binding and neutralizing antibodies titers propose the potential use of this conjugate for the development of immunotherapeutic reagents and/or STa-based vaccine against ETEC K99(+).
authors.affiliation: Department of Large Animal Clinical Sciences, College of Veterinary Medicine Michigan State University, MI, East Lansing, 48823, USA. aref71@hotmail.com
authors.forename: Nasr-Eldin M
authors.initials: NE
authors.lastname: Aref
authors.forename: A Mahdi
authors.initials: AM
authors.lastname: Saeed
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D057134:Antibodies, Neutralizing / Q000096:biosynthesis; D000942:Antigens, Bacterial / Q000302:isolation & purification; D001427:Bacterial Toxins / Q000737:chemistry / Q000276:immunology* / Q000302:isolation & purification*; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology / Q000517:prevention & control / Q000628:therapy; D003432:Cross-Linking Reagents; D054307:Enterotoxigenic Escherichia coli / Q000276:immunology* / Q000472:pathogenicity; D004768:Enterotoxins / Q000737:chemistry / Q000276:immunology* / Q000302:isolation & purification*; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D004927:Escherichia coli Infections / Q000276:immunology / Q000517:prevention & control / Q000628:therapy / Q000662:veterinary; D029968:Escherichia coli Proteins; D022361:Escherichia coli Vaccines / Q000302:isolation & purification; D007158:Immunologic Techniques / Q000662:veterinary; D066298:In Vitro Techniques; D051379:Mice; D009500:Neutralization Tests / Q000662:veterinary; D011817:Rabbits; D012710:Serum Albumin, Bovine
chemical_list: D000907:Antibodies, Bacterial; D057134:Antibodies, Neutralizing; D000942:Antigens, Bacterial; D001427:Bacterial Toxins; D003432:Cross-Linking Reagents; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D022361:Escherichia coli Vaccines; C034151:heat stable toxin (E coli); D012710:Serum Albumin, Bovine