Polysaccharide and glycoconjugate vaccines

A vaccine containing one or more glycoconjugate antigens prepared, by the following steps:

• A:
• Activation of an endotoxin-free capsular polysaccharide antigen to polyfunctional capsular polysaccharide through a diamino-alkyl spacer introduced via:
• A1:
• O-de-hydrogen uncoupling obtained by introduction of reactive carbonyl groups with an oxidative agent to generate aldehyde groups in the presence of borate ions when the reaction is performed in aqueous solvent;
• said groups being then reacted with the diamino-alkyl spacer in the presence of a reducing agent, or via
• A2:
• linkage of the diamino-alkyl spacer to the already present reactive carbonyl residues in the form of carboxyl groups by water-insoluble carbodiimide, in the presence of organic solvents,
• B:
• Activation of the immunogenic carrier protein via bis-succinimidyl ester of an aliphatic bicarboxylic acid, resulting in a poly-functional protein through monosuccinimidylesters of the Lysine residues
• C:
• Coupling of the activated poly-fu notional carrier protein to the activated endotoxin-free poly-functional capsular polysaccharide, via the monosuccinimidylesters of the Lysine residues of the protein and the amino groups of the polysaccharide wherein said endotoxin-free capsular polysaccharide antigen is prepared by the removal of a contaminating endotoxin by affinity-binding of the lipid A moiety of LPS with synthetic anti-endotoxin peptides featuring retro-inverted amino acid sequences and which is administered by the subcutaneous, intra muscular and intra dermal route in the dose-range 0.1-100 ug, in single or multiple injections.