ODN TTAGGG control - TLR9 Ligand

Negative control for ODN TTAGGG

Toll-like receptor 9 (TLR9) recognizes specific unmethylated CpG oligonucleotide (ODN) sequences that distinguish microbial DNA from mammalian DNA.

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 ODN 2088 which derives from a stimulatory ODN by replacement of 3 bases [3].

Inhibitory ODNs act by disrupting the colocalization of CpG ODNs with TLR9 in endosomal vesicles without affecting cellular binding and uptake.

ODN TTAGGG Control is a negative control for the inhibitory ODN TTAGGG.

References:

1. Krieg AM. et al., 1998. Sequence motifs in adenoviral DNA block immune activation by stimulatory CpG motifs. Proc Natl Acad Sci USA. 95(21): 12631-6.
2. Gursel I. et al., 2003. Repetitive elements in mammalian telomeres suppress bacterial DNA-induced immune activation. J Immunol. 171(3):1393-400.
3. Stunz LL. et al., 2002. Inhibitory oligodinucleotides specifically block effects of stimulatory CpG oligonucleotides in B cells. Eur J Immunol. 32(5): 1212-22.