This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Brandl, K. Articles by Falk, W. Search for Related Content PubMed PubMed Citation Articles by Brandl, K. Articles by Falk, W. Social Bookmarking                   What's this?

A designed TLR4/MD-2 complex to capture LPS

Department of Internal Medicine I, University of Regensburg, Regensburg, Germany, katharina.brandl{at}klinik.uni-regensburg.de

Thomas Glück

Department of Internal Medicine I, University of Regensburg, Regensburg, Germany

Pia Hartmann

Department of Internal Medicine I, University of Regensburg, Regensburg, Germany

Bernd Salzberger

Department of Internal Medicine I, University of Regensburg, Regensburg, Germany

Werner Falk

Department of Internal Medicine I, University of Regensburg, Regensburg, Germany

The family of Toll-like receptors (TLRs) is involved in the defense of an organism to microbial attack. TLR4-induced signaling is involved in infectious diseases, chronic inflammatory diseases and sepsis; therefore, we aimed at modulating TLR4-signaling via ligand-binding soluble receptors. Because recognition of microbial structures shows some species-specific traits, we specifically selected the mouse model for later in vivo studies. We first prepared the N-terminally Flag-tagged mouse (m) recombinant (r) soluble (s) fusion proteins mrsTLR4-IgGFc (T4Fc) and mrsMD-2 in Drosophila melanogaster Schneider 2 (S2) cells. The function of these molecules was tested by inhibition of synthesis of pro-inflammatory cytokines after stimulation of mouse macrophage RAW 264.7 cells with purified lipopolysaccharide (LPS). T4Fc alone had no inhibitory activity; however, a T4Fc/MD-2 complex blocked LPS activity. By analogy with `cytokine traps', we then prepared a designer molecule (LPS-Trap) by fusing MD-2 to the C-terminus of soluble TLR4 via a flexible linker. LPS-Trap significantly inhibited TNF production by LPS-stimulated RAW 264.7 cells. Thus, the T4Fc/MD-2 complex as well as the LPS-Trap blocked LPS activity in vitro and might thus represent a new therapeutic option in sepsis by neutralization of TLR4-activating ligands.

Key Words: Designer molecule • LPS • MD-2 • signaling • soluble TLR4

CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?