Physiopathological effects of Escherichia coli O157:H7 inoculation in weaned calves fed with colostrum containing antibodies to EspB and Intimin

Escherichia coli O157:H7 is responsible for severe intestinal disease and hemolytic uremic syndrome (HUS), a serious systemic complication which particularly affects children. Cattle are the primary reservoir for E. coli O157:H7 and the main source of infection for humans. In this study, we evaluated the ability of transferred maternal colostral antibodies against γ-Intimin C280 and EspB, to protect young weaned calves from E. coli O157:H7 infection. Hyperimmune colostra were obtained by immunization of pregnant cows with a mix of the mentioned antigens. All vaccinated cows mounted a significant IgG response against γ-Intimin C280, and EspB in sera and colostra. Colostrum-fed calves also exhibited high serum IgG titers against γ-Intimin C280 and EspB along with a rise in mucosal γ-Intimin C280-specific IgG antibodies at recto-anal junction and ileum. Additionally, 70 day-old calves received a challenge with E. coli O157:H7 but no reduction in total bacterial shedding or frequency of E. coli O157:H7 excretion from these calves was observed. Most tissue samples showed granulocyte focal infiltrations of the lamina propria and enterocyte erosion. In conclusion, up to the 70th day, the passively acquired γ-Intimin-C280 and EspB-IgG antibodies present in sera and recto-anal mucosa reached a titer insufficient to reduce EHEC O157 shedding and damages of experimentally inoculated young calves.

Instituto de Patobiología

Fil: Rabinovitz, Bettina Carol. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; Argentina

Fil: Vilte, Daniel Alejandro. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; Argentina

Fil: Larzabal, Mariano. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina

Fil: Abdala, Alejandro Ariel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela; Argentina

Fil: Galarza, Roxana Ivon. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela; Argentina

Fil: Zotta, Elsa. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Fisiología. Laboratorio de Fisiopatogenia; Argentina

Fil: Ibarra, Cristina E. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Fisiología. Laboratorio de Fisiopatogenia; Argentina

Fil: Mercado, Elsa Cristina. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; Argentina

Fil: Cataldi, Angel Adrian. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina