Nanoparticles have emerged as the platform of choice to improve the efficacy and safety of
subunit vaccines. A major challenge underlying the use of nanomaterials in
vaccines lies in the particle designs that can efficiently target and activate the antigen-presenting cells, especially dendritic cells. Here we show a
toll-like receptor 9 (TLR-9) agonist and
antigen coloaded,
silica nanoparticles (SiNPs) are able to accumulate in antigen presenting cells in the draining lymph nodes after injection.
Vaccine loaded SiNPs led to dramatically enhanced induction of
antigen-specific B and T cell responses as compared to soluble
vaccines, which in turn drove a protective antitumoral immunity in a murine
tumor model. Additionally, SiNP
vaccines greatly reduced the production of systemic proinflammatory
cytokines and completely abrogated
splenomegaly, key systemic toxicities of TLR-9 agonists that limit their advances in clinical applications. Our results demonstrate that structure-optimized
silica nanocarriers can be used as an effective and safe platform for targeted delivery of
subunit vaccines.