Subversion of Toll-like receptor signaling by a unique family of bacterial Toll/interleukin-1 receptor domain-containing proteins

Summary, in English

Pathogenic microbes have evolved sophisticated molecular strategies to subvert host defenses. Here we show that virulent bacteria interfere directly with Toll-like receptor (TLR) function by secreting inhibitory homologs of the Toll/interleukin-1 receptor (TIR) domain. Genes encoding TIR domain containing–proteins (Tcps) were identified in Escherichia coli CFT073 (TcpC) and Brucella melitensis (TcpB). We found that TcpC is common in the most virulent uropathogenic E. coli strains and promotes bacterial survival and kidney pathology in vivo. In silico analysis predicted significant tertiary structure homology to the TIR domain of human TLR1, and we show that the Tcps impede TLR signaling through the myeloid differentiation factor 88 (MyD88) adaptor protein, owing to direct binding of Tcps to MyD88. Tcps represent a new class of virulence factors that act by inhibiting TLR- and MyD88-specific signaling, thus suppressing innate immunity and increasing virulence.

• Author: Christine Cirl; Andreas Wieser; Manisha Yadav; Susanne Duerr; Sören Schubert; Hans Fischer; Dominik Stappert; Nina Wantia; Nuria Rodriguez; Hermann Wagner; Catharina Svanborg; Thomas Miethke
• Department/s: Division of Microbiology, Immunology and Glycobiology - MIG
• Publishing year: 2008
• Language: English
• Pages: 399-406
• Publication/Series: Nature Medicine
• Volume: 14
• Issue: 4
• Links: http://dx.doi.org/10.1038/nm1734
• Document type: Journal article
• Publisher: Nature Publishing Group
• Topic: Microbiology in the medical area; Immunology in the medical area
• Status: Published
• ISBN/ISSN/Other: ISSN: 1546-170X