Conjugating Low Molecular Mass Carbohydrates to Proteins 1. Monitoring the Progress of Conjugation

Abstract

There are many applications of neoglycoconjugates in the life sciences, of which probably the most promising is their use as immunogenic materials in developing vaccines for infectious diseases and cancer. Polysaccharides, such as the O-specific polysaccharide part of lipopolysaccharides and capsular polysaccharides, are important natural antigens but poor immunogens. They are classified as T-independent (TI) antigens, and the level and the spectrum of antibodies produced after immunization with carbohydrate antigens is insufficient to render protection. Chemical linking of carbohydrates to proteins can transform them into T cell-dependent antigens. As a result, multiple injections of neoglycoconjugates can sharply boost antibody titers way beyond those observed as a result of priming with TI antigens. This is, essentially, the rationale behind the concept of synthetic vaccines, which was pre expected to be free from some of the drawbacks of cellular vaccines. This chapter describes monitoring the progress of conjugation of synthetic, linker-equipped oligosaccharides to proteins. Practical hints, which may be useful in modifying the protocol described in the chapter to better suit a particular situation, are also included.