Modified meningococcal group b polysaccharide for conjugate vaccine

Abstract

The group B polysaccharide of Neisseria meningitidis is chemically modified to enhance the immune response thereto, thereby providing cross-reactive antibodies of high affinity. The N-acetyl group of the sialic acid residues of the polysaccharide has been substituted by the N-propionyl group, and this modified antigen then conjugated to a physiologically-acceptable protein such as tetanus toxoid. This conjugate vaccine has been found to raise high titers of high affinity group B IgG antibodies and would be useful against meningitis caused by group B N. meningitidis or by E. coli KI organisms.