|
G-ODN
Guanosine-rich inhibitory oligonucleotide
Toll-Like Receptor 9 (TLR9) detects unmethylated CpG dinucleotides in bacterial or viral DNA inducing strong immunostimulatory effects. TLR9 activation can be mimicked by synthetic phosphorothioate-stabilized oligodeoxynucleotides (ODN) containing immune stimulatory “CpG motifs”.
Recent studies suggest the existence of DNA sequences that can neutralize the stimulatory effect of CpG ODNs [1]. These sequences are characterized by three consecutive Gs downstream of a C or A, addition of a fourth G (G-tetrads) increases the inhibitory capability. The most potent inhibitory sequences are (TTAGGG)4 found in mammalian telomeres [2] and guanosine-rich ODN (G-ODN), which contains a string of 5 Gs [3]. G-ODN was suppressive in murine DC and macrophages as well as in human plasmacytoid DC [3].
Inhibitory ODNs act by disrupting the colocalization of CpG ODNs with TLR9 in endosomal vesicles without affecting cellular binding and uptake.
Specificity: murine TLR9 antagonist
Working concentration: 100 nM - 10 µM
Solubility: 5 mg/ml in water
G-ODN sequence
5’- ctc cta ttg ggg gtt tcc tat -3’ (21 mer)
Note: Bases are phosphorothioate (nuclease resistant).
Quality control
- Biological activity is tested using HEK-Blue™ TLR9 cells.
- The absence of bacterial contamination (endotoxins, peptidoglycans) is controlled using HEK-Blue™ TLR2 and HEK-Blue™ TLR4 cells. |