Bacterial CpG-DNA and lipopolysaccharides activate Toll-like receptors at distinct cellular compartments

Recognition by innate immune cells of the pathogen associated molecular patterns (PAMP) lipopolysaccharide (LPS) from Gram-negative bacteria and bacterial CpG-DNA depends on Toll-like receptor4 (TLR4) and TLR9, respectively. To define differences in the response to these distinct PAMP we compared a key intracellular event, namely recruitment of myeloid differentiation marker 88 (MyD88) to the respective PAMP-initiated TLR signaling. Using MyD88-GFP fusion protein expressing macrophages we demonstrate that LPS and CpG-DNA trigger signaling from two different cellular locations: theformer at the cell membrane and the latter at the lysosomal compartment. While LPS does not require endocytosis to functionally…

• DF
  Deutsche Forschungsgemeinschaft

  Awards: SFB 45, SFB 456
• BF
  Bundesministerium für Bildung und Forschung

  Award: This work was