LPS BASED VACCINES

摘要

The removal of the glycosidic phosphate from the reducing end of the derived LPS molecule creates an aldehydo functionality which causes the formation of an immunologically dominant neo-epitope. Conjugation to the reducing end of a carbohydrate molecule following removal of the glycosidic phosphate traps the reducing glucosamine residue in an open-chain form which surprisingly was found to dominate the immune response. We therefore modified our conjugation strategy to avoid this open-chain form, by utilising the amino functionality created by the isolated amidase activity from Dictyostelium discoideum, concomitant with a unique blocking and un-blocking strategy to protect the immunologically important phosphoethanolamine inner core residue. These antigenic structures are useful in producing vaccines and compounds helpful in combating Gram-negative bacteria. Also described are specific structures of the carbohydrate molecules derived from a variety of Gram-negative bacteria, which when presented appropriately as a glycoconjugate will facilitate a functional immune response to the target core oligosaccharide region.