Gold nanocluster-based vaccines for dual-delivery of antigens and immunostimulatory oligonucleotides

Abstract

We here report a facile one-pot synthesis of fluorescent gold nanoclusters (AuNCs) via the peptide biomineralization method, which can elicit specific immunological responses. The as-prepared peptide-protected AuNCs (peptide–AuNCs) display strong red fluorescence, and more importantly, as compared to the peptide alone, the immune stimulatory ability of the resulting peptide–AuNCs can not only be retained, but can also be efficaciously enhanced. Moreover, through a dual-delivery of antigen peptides and cytosine–phosphate–guanine (CpG) oligodeoxynucleotides (ODNs), the as-prepared peptide–AuNC–CpG conjugates can also act as smart self-vaccines to assist in the generation of high immunostimulatory activity, and be applied as a probe for intracellular imaging. Both in vitro and in vivo studies provide strong evidence that the AuNC-based vaccines may be utilized as safe and efficient immunostimulatory agents that are able to prevent and/or treat a variety of ailments.