Poly(I:C)/c-GAMP/Alum ternary adjuvant system synergistically enhances the immunogenicity of glycopeptide antigen

The highly glycosylated mucin 1 (MUC1) serves as a promising target for cancer vaccines. However, the weak immunogenicity of MUC1 greatly impedes its application. Here, we covalently linked a MUC1 glycopeptide to carrier protein bovine serum albumin (BSA), and the resulting BSA-MUC1 conjugate was integrated with a ternary adjuvant system comprising TLR3 agonist poly(I:C), STING agonist c-GAMP, and Alum adjuvant. Compared to adjuvant-free and Alum-adjuvanted groups, the ternary adjuvant group induced 18.3- and 10.9-fold increases in MUC1-specific IgG titers, and effectively suppressed tumor growth. These findings may propose a straightforward yet highly effective strategy for designing vaccines, offering promising prospects in cancer treatment.