Evaluation of a LPS-based glycoconjugate vaccine against bovineEscherichia colimastitis: Formation of LPS Abs in cows after immunization withE. colicore oligosaccharides conjugated to hemocyanine

Abstract

The immune response of cows against the core oligosaccharide of Escherichia coli rough mutants (core types R1-R4, K-12 and J-5) was investigated after immunization with a synthetic glycoconjugate composed of deacylated LPS conjugated to hemocyanine (22 animals). Ab formation was measured by ELISA using LPS or deacylated LPS conjugated to BSA as an Ag. The glycoconjugate immunogens were used to vaccinate cows (36 animals), which were then challenged intramammarily with E. coli O 157 (K1 negative, R1 core type). Compared with control groups no protection was observed, although high titers against the R1 core type were detected in vaccinated animals. Western blots using the immune sera showed that the Ab response was directed against the core region and not against the O-antigen, which may explain the failure of the vaccine.

LPS core type diversity in the Escherichia coli species and associations with phylogeny and virulence gene repertoire

“…The high prevalence of the R1 core type we observed had already been described in previous studies analyzing avian pathogenic E. coli strains or clinical and commensal isolates (15–17). Another finding consistent with previous reports is the low prevalence of R2 and R4 core types.…”

“…The high prevalence of the R1 core type we observed had already been described in previous studies analyzing avian pathogenic E. coli strains or clinical and commensal isolates (15)(16)(17).…”

“…It is The copyright holder for this preprint this version posted March 22, 2021. ; https://doi.org/10.1101/2021.03.22.436425 doi: bioRxiv preprint So far, the distribution of LPS core types has been investigated in a restricted number of reports. The R1 type is the most prevalent of all core types, with R2, R3, R4 and K-12 core types having significantly lower prevalences (15)(16)(17).…”

“…So far, the distribution of LPS core types has been investigated in a restricted number of reports. The R1 type is the most prevalent of all core types, with R2, R3, R4 and K-12 core types having significantly lower prevalences (15–17).…”

Lipopolysaccharide core type diversity in the Escherichia coli species in association with phylogeny, virulence gene repertoire and distribution of type VI secretion systems

“…So far, the distribution of LPS core types has been investigated in a restricted number of reports. The R1 type is the most prevalent of all core types, with R2, R3, R4 and K-12 core types having significantly lower prevalences [17–19].…”