Innovative Manufacturing Techniques for Polysaccharide-Protein Conjugate Vaccines

This project develops a conjugate vaccine against Shigella flexneri 2a utilizing cGMP-compatible manufacturing processes. The antigenic component of the vaccine is deacylated-polysaccharide from the bacterial LPS that has an average of one O-antigen repeat unit per polysaccharide molecule. The polysaccharide is deacylated by a biological process, and has a core structure with intact phophosphoryl groups. It is expected that phosphorylated core components will elicit antibodies that cross-react with LPS of other strains and species of Shigella that share these core epitopes. Phase I research studies will provide a cGMP-compatible method for producing the conjugate vaccine, and Phase I Option studies will evaluate the immunogenicity of the vaccine, and its potential to elicit cross-reactive antibodies against several serotypes of S. flexneri and against other Shigella species.