Common epitopes in LPS of different Enterobacteriaceae are associated with an immune response against Escherichia coli O157 in bovine serum samples.
Epidemiological studies in both humans and animals conducted in Mexico have shown that the isolation frequency of Escherichia coli O157 : H7 is low. In a previous study, IgG antibodies against E. coli O157, O7 and O116 LPS were found in serum samples from children and adults with no previous history of E. coli O157 : H7 infection. The present study was designed to determine whether a similar immune response against E. coli O157 : H7 and other antigenically related bacteria was present in bovine serum samples. A total of 310 serum samples from different herds in Mexico was analysed by microagglutination assays against different enterobacterial antigens, including E. coli O157. Microagglutination assays were positive against E. coli O7 (55 %), O116 (76 %) and O157 (36 %), Escherichia hermannii (15 %), Salmonella enterica serotype Urbana (14 %) and Salmonella enterica subsp. arizonae (40 %). These results were confirmed using a specific ELISA with purified LPS. A positive reaction was observed against the LPS of E. coli O7 (29 %), O116 (12 %) and O157 (22 %), E. hermannii (4 %), Salmonella Urbana (13 %) and S. enterica subsp. arizonae (12 %). Serum absorption studies of positive serum samples indicated the existence of at least three common epitopes shared by the LPS of E. coli O7, O116 and O157, and two others between E. coli O157 and Salmonella Urbana and S. enterica subsp. arizonae. A bactericidal assay against E. coli O157 : H7 using 31 bovine serum samples was performed, and 22 (71 %) of these serum samples gave positive results. The data demonstrated that bovine serum showed a response against different enterobacteria, including E. coli O157, and that this response could be due to the presence of shared epitopes in the LPS of these organisms.
Navarro
Armando
A
Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, D. F. 04510, Mexico.
Eslava
Carlos
C
Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, D. F. 04510, Mexico.
García de la Torre
Guadalupe
G
Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, D. F. 04510, Mexico.
León
Luis Antonio
LA
Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, D. F. 04510, Mexico.
Licona
Delia
D
Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, D. F. 04510, Mexico.
León
Lemuel
L
Universidad Autónoma del Estado de México, Mexico.
Zarco
Luis Alberto
LA
Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Ciudad Universitaria, D. F., Mexico.
Cravioto
Alejandro
A
Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, D. F. 04510, Mexico.
D000372:Agglutination Tests / Q000379:methods; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood*; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology*; D003429:Cross Reactions; D004755:Enterobacteriaceae / Q000276:immunology*; D004756:Enterobacteriaceae Infections / Q000453:epidemiology / Q000276:immunology / Q000662:veterinary*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D000939:Epitopes / Q000276:immunology*; D008070:Lipopolysaccharides / Q000276:immunology*; D008800:Mexico / Q000453:epidemiology; D050296:Microbial Viability; D016036:Seroepidemiologic Studies; D044967:Serum / Q000276:immunology
D000907:Antibodies, Bacterial; D000939:Epitopes; D008070:Lipopolysaccharides