Synthesis of a conjugate of 3´-sialyllactoside with recombinant flagellin as a carrier protein and assessment of its immunological activity in comparison with that of a similar hemocyanin-based conjugate

In the framework of a project directed to the design of synthetic cancer vaccines based on carbohydrate chains of tumor-associated gangliosides, a new prototype cancer vaccine, a polyvalent carbohydrate-protein conjugate 1 with ∼11 3´-sialyllactoside ligands conjugated to one molecule of recombinant flagellin was synthesized. Dendritic cell vaccines were designed using the conjugate 1 and a neoglycoconjugate 2 consisting of ∼400 3´-sialyllactose residues linked to hemocyanin from a snail Megathura crenulata (KLH). Comparative ELISA study was conducted to assess the induction of carbohydrate-specific immunoglobulins IgM and IgG after immunization of mice with conjugates 1 and 2 and dendritic cells loaded with 1 and 2. Synthetic polyacrylamide carrier conjugated to 3´-sialyllactose ligands and B16F0 melanoma cells were used as coating antigens.