Signal Transduction and Negative Regulation Activated by CpG DNA

Abstract: CpG DNA containing unmethylated CpG dinucleotides in particular base contexts (CpG motifs) have characteristic immunostimulatory effects. The release of unmethylated CpG DNA during infection provides a angerous signal?to the innate immune system， triggering a protective immune response that enhances the ability of the host to eliminate the pathogen. The signal transduction activated by CpG DNA includes the cellular internalization of CpG DNA， the interaction with Toll-like receptor 9 (TLR9) and the subsequent signal cascade reaction. The intensity and duration of CpG DNA/TLR9 signaling can be negatively modulated by intracellular regulators， transmembrane proteins regulators and the reduction of TLR9 expression. In addition， three structurally distinct classes of CpG ODNs representing differential immunomodulatory activities are capable of stimulating cells through differential signaling. Above all， the study of the signaling mechanism of CpG DNA may provide a deep understanding toward CpG-mediated immune response.

CSTR: 32200.14.cjcb.2006.04.0014