| abstract |
A modified polysaccharide, in particular a modified Neisseria meningitides serogroup A polysaccharide, which retains immunogenicity but has improved stability. Typically, the modified polysaccharide is prepared by reacting a capsular polysaccharide, or oligosaccharide fragment thereof, with a bifunctional reagent such as CDI, followed by reaction with an amino compound, such dimethylamine. Modified polysaccharide-protein conjugates and vaccines prepared from such conjugates are also described. |