Functional analysis of bovine TLR5 and association with IgA responses of cattle following systemic immunisation with H7 flagella

Amin Tahoun, Kirsty Jensen, Yolanda Corripio-Miyar, Sean P McAteer, Alexander Corbishley, Arvind Mahajan, Helen Brown, David Frew, Aude Aumeunier, David G. E. Smith, Tom N McNeilly, Elizabeth J Glass, David L Gally

    Research output: Contribution to journalArticle

    15 Citations (Scopus)
    30 Downloads (Pure)

    Abstract

    Flagellin subunits are important inducers of host immune responses through activation of TLR5 when extracellular and the inflammasome if cytosolic. Our previous work demonstrated that systemic immunization of cattle with flagella generates systemic and mucosal IgA responses. The IgA response in mice is TLR5-dependent and TLR5 can impact on the general magnitude of the adaptive response. However, due to sequence differences between bovine and human/murine TLR5 sequences, it is not clear whether bovine TLR5 (bTLR5) is able to stimulate an inflammatory response following interaction with flagellin. To address this we have examined the innate responses of both human and bovine cells containing bTLR5 to H7 flagellin from E. coli O157:H7. Both HEK293 (human origin) and embryonic bovine lung (EBL) cells transfected with bTLR5 responded to addition of H7 flagellin compared to non-transfected controls. Responses were significantly reduced when mutations were introduced into the TLR5-binding regions of H7 flagellin, including an R90T substitution. In bovine primary macrophages, flagellin-stimulated CXCL8 mRNA and secreted protein levels were significantly reduced when TLR5 transcript levels were suppressed by specific siRNAs and stimulation was reduced with the R90T-H7 variant. While these results indicate that the bTLR5 sequence produces a functional flagellin-recognition receptor, cattle immunized with R90T-H7 flagella also demonstrated systemic IgA responses to the flagellin in comparison to adjuvant only controls. This presumably either reflects our findings that R90T-H7 still activates bTLR5, albeit with reduced efficiency compared to WT H7 flagellin, or that other flagellin recognition pathways may play a role in this mucosal response.

    Original languageEnglish
    Article number9
    Number of pages15
    JournalChemical Engineering Research and Design
    Volume46
    DOIs
    Publication statusPublished - 19 Feb 2015

    Keywords

    • Animals
    • Cattle
    • Escherichia coli O157
    • Flagella
    • Flagellin
    • HEK293 Cells
    • Humans
    • Immunization
    • Immunoglobulin A
    • Toll-Like Receptor 5

    Fingerprint Dive into the research topics of 'Functional analysis of bovine TLR5 and association with IgA responses of cattle following systemic immunisation with H7 flagella'. Together they form a unique fingerprint.

  • Cite this

    Tahoun, A., Jensen, K., Corripio-Miyar, Y., McAteer, S. P., Corbishley, A., Mahajan, A., Brown, H., Frew, D., Aumeunier, A., Smith, D. G. E., McNeilly, T. N., Glass, E. J., & Gally, D. L. (2015). Functional analysis of bovine TLR5 and association with IgA responses of cattle following systemic immunisation with H7 flagella. Chemical Engineering Research and Design, 46, [9]. https://doi.org/10.1186/s13567-014-0135-2