Pachathundikandi SK Tegtmeyer N Arnold IC Lind J Neddermann M Falkeis-Veits C Chattopadhyay S Brönstrup M Tegge W Hong M Sticht H Vieth M Müller A Backert S 2019 Toll-like receptor TLR5 recognizes a conserved domain, termed D1, that is present in flagellins of several pathogenic bacteria but not in Helicobacter pylori. Highly virulent H. pylori strains possess a type IV secretion system (T4SS) for delivery of virulence factors into gastric epithelial cells. Here, we show that one of the H. pylori T4SS components, protein CagL, can act as a flagellin-independent TLR5 activator. CagL contains a D1-like motif that mediates adherence to TLR5+ epithelial cells, TLR5 activation, and downstream signaling in vitro. TLR5 expression is associated with H. pylori infection and gastric lesions in human biopsies. Using Tlr5-knockout and wild-type mice, we show that TLR5 is important for efficient control of H. pylori infection. Our results indicate that CagL, by activating TLR5, may modulate immune responses to H. pylori. application/pdf https://sonar.ch/global/documents/3667 eng info:eu-repo/semantics/altIdentifier/doi/10.1038/s41467-019-13506-6 info:eu-repo/semantics/altIdentifier/pmid/31844047 info:eu-repo/semantics/openAccess Nature communications. - 2019 Animals Bacterial Proteins Biopsy Disease Models, Animal Female Gastric Mucosa Helicobacter Infections Helicobacter pylori Host-Pathogen Interactions Humans Mice Mice, Knockout NF-kappa B Signal Transduction Toll-Like Receptor 5 Type IV Secretion Systems T4SS-dependent TLR5 activation by Helicobacter pylori infection. http://purl.org/coar/resource_type/c_6501