Novel vaccine adjuvant LPS-Hydrogel for truncated basic fibroblast growth factor to induce antitumor immunity.

The need to enhance the immunogenicity of tumor-associated antigens and modulate the resulting immune responses has prompted the development of new adjuvants. We prepared a novel adjuvant, lipopolysaccharides (LPS) loaded thermosensitive hydrogel (LPS-Hydrogel), for truncated basic fibroblast growth factor (tbFGF) peptide to enhance immunological responses and improve therapeutic effects in cancer. When co-formulated with tbFGF, LPS-Hydrogel formed antigen-adjuvant complexes, which enhanced antibody and cell-mediated responses in mice, thus promoting a more balanced antibody-mediated and cytotoxic T lymphocyte (CTL)-mediated immune response to inhibit tumor growth and metastases in vivo. Furthermore, the secretion of IFN-γ and IL-4 was detected, confirming activation of the two immune responses in vivo. There were no significant systemic toxicities observed with tbFGF-LPS-Hydrogel treatment. These results suggested that the thermosensitive and biodegradable LPS-Hydrogel was a novel adjuvant and carrier for peptide vaccines in cancer immunotherapy.