Immunoadjuvant efficacy of N-carboxymethyl chitosan for vaccination via dendritic cell activation.

To induce humoral- and cell-mediated immune responses in protein-based vaccinations, immunoadjuvants are needed. In this study, we investigated the immunoadjuvant effect of N-carboxymethyl chitosan (N-CMCh) on the vaccination system through dendritic cell activation. The results showed that N-CMCh nanoparticle enhanced the secretion of cytokines (interleukin [IL]-6, IL-12p70, and tumor necrosis factor-α) and antigen uptake in bone marrow-derived dendritic cells. This activated antigen-specific Th1 cell responses, including IL-2 and interferon-gamma production and proliferation. In addition, N-CMCh delayed the dissemination of ovalbumin (OVA) from an injection site in female C57BL/6 mice. As a result, in the subcutaneous vaccination, OVA-N-CMCh nanoparticles enhanced both humoral and cell-mediated vaccine responses.