Enhanced Immunostimulatory Properties in CpG-Oligonucleotides Modified by Gold Nanoparticles

Whether the immunostimulatory effects of CpG-oligonucleotides (CpG ODNs) could be enhanced by the use of gold nanoparticles (Au-NP) was investigated. The CpG ODNs were modified by the Au-NP (CpG / Au-NP) and their uptake and distribution in murine N9 microglial cells were studied. The immunostimulatory effects of CpG / Au-NP on N9 cells, human B cells and plamacytoid dendritic cells (pDCs) were examined. Results showed that the uptake of CpG / Au-NP in N9 cells was much higher than that of CpG ODNs and CpG / Au-NP localized in the cytoplasm of N9 cells. The amount of INF-alpha and IL12p40 in N9 cells was increased greatly by the use of Au-NP. And the amount of IL-6 in B cells and IFN-alpha in pDCs was also significantly increased, while the activation of B cells was not changed. These results reveal that the Au-NP can be used as a delivery media for the oligonucleotides-based therapeutics.