2019 Volume 34 Issue 1 Pages 46-51
CpG ODN, the ligand for TLR9, is expected to be used as an immune adjuvant for vaccines against cancer and infectious diseases. We have been studying on nanostructured nucleic acids to reveal the relationships among their structural properties, interaction with cells, and adjuvant activity. As results, it was found that MSR1 is involved in the uptake of the nanostructured nucleic acids by TLR9-expressing cells. In addition, we developed several types of nanostructured nucleic acids with diverse structural properties using DNA nanotechnology, and demonstrated that they were useful for delivering CpG ODN to TLR9-expressing cells and for increasing cytokine release from the cells. Then, we developed DNA hydrogels by connecting nanostructured nucleic acids using self-gelatinizable nucleic acid technology. The DNA hydrogels containing CpG ODN can stimulate the innate immune system and have a sustained release property of CpG ODN, so that they are quite useful delivery systems with adjuvant activity for cancer immunotherapy.
