Characterisation and functional analysis of canine TLR5

Area of Science:

• Immunology
• Genetics
• Canine Health

Background:

• Toll-like receptor 5 (TLR5) is crucial for innate immunity, recognizing bacterial flagellin.
• Understanding canine TLR5 is vital for canine health and disease research.

Purpose of the Study:

• To characterize the single exon TLR5 gene in Chinese rural dogs.
• To investigate the functional activity and immune response of canine TLR5.

Main Methods:

• Sequence analysis of the canine TLR5 gene.
• Construction and transfection of expression plasmids in HEK293T cells.
• Stimulation assays with flagellin and analysis of cytokine expression in PBMCs.

Main Results:

• Identified a 2577-nucleotide canine TLR5 open reading frame encoding an 858-amino acid protein.
• Canine TLR5 showed high sequence identity to vulpine and feline TLR5, lower to human TLR5.
• Functional assays confirmed canine TLR5's ability to respond to Salmonella flagellin, upregulating TLR5 mRNA and cytokine (IL-8, IL-6, IL-1β) expression in PBMCs.

Conclusions:

• The characterized canine TLR5 is a functional homolog of TLR5.
• Canine TLR5 plays a role in the immune response against bacterial pathogens like Salmonella.
• This study provides foundational knowledge for canine immunology and disease resistance.