The Production and Characterization of Synthetic Glycoconjugate Vaccines

Chemical conjugation of polysaccharides to protein carriers has become essential in carbohydrate vaccine development to enhance the poor immunogenicity of glycans. Neutral and uncharged carbohydrates induce T-cell independent responses, failing to produce robust IgG antibodies or sustained T-cell memory and conjugating native or synthetic glycans with carrier proteins such as the Cross-Reactive-Material-197 (CRM197) diphtheria toxin mutant, tetanus toxoid, or protein D of H. influenzae eliciting T-cell-dependent immune responses and class switching that produces high-affinity antibodies. This chapter describes the most commonly used synthetic glycoconjugates preparation strategy involving a spacer and a linker carrying a functional group, mostly amine, that couples the synthetic glycan to the carrier protein through its primary amine side chains of lysine residues and N-terminus. Our detailed protocol aims to advance the development of carbohydrate-binding antibodies that target tumor-associated carbohydrate antigens and expand our toolbox in the war against cancer.