The phosphothioated oligodeoxyribonucleotide(ODN) and antisense strands (AS) of siRNAs were linked using 6 units of C3 carbon chain linker, (CH 2 ) 3 The sequence of firefly luciferase-specific 25/27mer siRNA (Luc1 R 25D/27), used for the CpG1668-Luc siRNA conjugate molecule, was published 34 . The correct formation of siRNA duplex was confirmed by in vitro Dicer cleavage assays. 0.5 μg of each ODN-siRNA construct was subjected to processing by 1U of Dicer (Ambion) in 37°C for 1.5 h, resolved with 15% polyacrylamide/7.5M urea gel and results of the dicing reaction were visualized with SYBR Gold staining (Invitrogen).