Capsular polysaccharide solubilisation and combination vaccines

摘要

Precipitated bacterial capsular polysaccharides can be efficiently re-solubilized using alcohols as solvents. The invention provides a process for purifying a bacterial capsular polysaccharide, comprising the steps of (a) precipitation of said polysaccharide, followed by (b) solubilization of the precipitated polysaccharide using ethanol. CTAB can be used for step (a). The material obtained, preferably following hydrolysis and sizing, can be conjugated to a carrier protein and formulated as a vaccine. Also, in vaccines comprising saccharides from both serogroups A and C, the invention provides that the ratio (w/w) of MenA saccharide:MenC saccharide is >1.

主权项

1. A method for conjugating a bacterial capsular polysaccharide to a carrier protein, comprising
(a) purifying the polysaccharide, comprising the steps of (i) precipitation of the polysaccharide using one or more cationic detergents, followed by (ii) solubilisation of the precipitated polysaccharide using an alcohol, and (b) conjugating the polysaccharide to a carrier protein,wherein the bacterial capsular polysaccharide is from Neisseria meningitidis serogroup A, Neisseria meningitidis serogroup W135, Neisseria meningitidis serogroup Y, Haemophilus influenzae or Streptococcus pneumoniae, wherein the method further comprises a step of hydrolysis to form oligosaccharides prior to step (b).