It remains a top research priority to develop immunotherapeutic approaches to induce potent
antigen-specific immune responses against
tumors. However, in spite of some promising results, most strategies are ineffective because they generate low numbers of
tumor-reactive cytotoxic T lymphocytes (CTLs). Here we designed a strategy to enhance
antigen-specific immune response via administering sulfosuccinimidyl-4-[N-maleimidomethyl] cyclohexane-1-carboxylate (
sulfo-SMCC)-conjugated
melanoma tumor antigen GP10025-33
peptide-coupled syngeneic spleen cells in a mouse model of
melanoma. We found that infusion of GP10025-33
peptide-coupled spleen cells significantly attenuated the growth of
melanoma in prophylactic and therapeutic immunizations. Consistent with these findings, the adoptive transfer of spleen cells from immunized mice to naïve syngeneic mice was able to transfer anti-
tumor effect, suggesting that GP10025-33
peptide-specific immune response was induced. Further studies showed that, CD8+ T cell proliferation and the frequency of
interferon (IFN)-γ-producing CD8+ T cells upon ex vivo stimulation by GP10025-33 were significantly increased compared to control groups.
Tumor antigen, GP10025-23 specific immune response was also confirmed by ELISpot and GP100-tetramer assays. This approach is simple, easy-handled, and efficiently delivering
antigens to lymphoid tissues. Our study offers an opportunity for clinically translating this approach into
tumor immunotherapy.