title: The intranasal vaccination of pregnant dams with Intimin and EspB confers protection in neonatal mice from Escherichia coli (EHEC) O157:H7 infection.
abstract: Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is responsible for intestinal disease and hemolytic uremic syndrome (HUS), a serious systemic complication which particularly affects children. In this study, we evaluated whether passive immunization protects from EHEC O157:H7 colonization and renal damage, by using a weaned BALB/c mouse model of infection. Recombinant proteins EspB and the carboxyl-terminal fragment of 280 amino acids of γ-intimin (γ-IntC280) were used in combination with a macrophage-activating lipopeptide-2 (MALP) adjuvant to immunize pregnant mice by the intranasal route. Neonatal mice were allowed to suckle vaccinated or sham-vaccinated dams until weaning when they were challenged by the oral route with a suspension of an E. coli O157:H7 Stx2+ strain. The excretion of the inoculated strain was followed for 72h. All vaccinated dams exhibited elevated serum IgG response against both γ-Int C280 and EspB. Passive immunization of newborn mice resulted in a significant increase in serum IgG titers against γ-Int C280 and a slight increase in EspB-specific antibodies. The neonates from vaccinated dams showed a significant reduction in EHEC O157:H7 colonization 48h post challenge. In addition, the level of plasma urea concentration, a marker of renal failure, was significantly higher in offsprings of sham-vaccinated mice. In conclusion, vaccination of pregnant dams with γ-Int C280 and EspB could reduce colonization and systemic toxicity of EHEC O157:H7 in their suckling offsprings.
authors.affiliation: Instituto de Patobiología, CICVyA, Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Buenos Aires, Argentina.
authors.forename: B C
authors.initials: BC
authors.lastname: Rabinovitz
authors.affiliation: Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Buenos Aires, Argentina.
authors.forename: M
authors.initials: M
authors.lastname: Larzábal
authors.affiliation: Instituto de Patobiología, CICVyA, Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Buenos Aires, Argentina.
authors.forename: D A
authors.initials: DA
authors.lastname: Vilte
authors.affiliation: Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Buenos Aires, Argentina. Electronic address: cataldi.angeladrian@inta.gob.ar.
authors.forename: A
authors.initials: A
authors.lastname: Cataldi
authors.affiliation: Instituto de Patobiología, CICVyA, Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Buenos Aires, Argentina.
authors.forename: E C
authors.initials: EC
authors.lastname: Mercado
mesh_terms: D018829:Adhesins, Bacterial / Q000276:immunology*; D000281:Administration, Intranasal; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D001425:Bacterial Outer Membrane Proteins / Q000276:immunology*; D004927:Escherichia coli Infections / Q000517:prevention & control*; D019453:Escherichia coli O157; D029968:Escherichia coli Proteins / Q000276:immunology*; D022361:Escherichia coli Vaccines / Q000008:administration & dosage / Q000276:immunology*; D005260:Female; D007112:Immunity, Maternally-Acquired; D007074:Immunoglobulin G / Q000097:blood; D051379:Mice; D008807:Mice, Inbred BALB C; D011247:Pregnancy; D011994:Recombinant Proteins / Q000276:immunology
chemical_list: D018829:Adhesins, Bacterial; D000907:Antibodies, Bacterial; D001425:Bacterial Outer Membrane Proteins; C087863:EaeB protein, E coli; D029968:Escherichia coli Proteins; D022361:Escherichia coli Vaccines; D007074:Immunoglobulin G; D011994:Recombinant Proteins; C073819:eaeA protein, E coli