Vaccines based on the cell surface carbohydrates of pathogenic bacteria

Abstract

Glycoconjugate vaccines, in which a cell surface carbohydrate from a micro-organism is covalently attached to an appropriate carrier protein are proving to be the most effective means to generate protective immune responses to prevent a wide range of diseases. The technology appears to be generic and applicable to a wide range of pathogens, as long as antibodies against surface carbohydrates help protect against infection. Three such vaccines, against Haemophilus influenzae type b, Neisseria meningitidis Group C and seven serotypes of Streptococcus pneumoniae, have already been licensed and many others are in development.This article discusses the rationale for the development and use of glycoconjugate vaccines, the mechanisms by which they elicit T cell-dependent immune responses and the implications of this for vaccine development, the role of physicochemical methods in the characterisation and quality control of these vaccines, and the novel products which are under development.

Development of a glycoconjugate vaccine to prevent meningitis in Africa caused by meningococcal serogroup X

“…particularly from early infancy, by converting the PS into a T-cell-dependent antigen (17,18). As recognized for other PS, conjugation to an appropriate carrier protein overcomes the limits of PS vaccines, such as poor efficacy in children less than 2 y, lack of immunological memory with poor booster responses, and relatively short duration of protection (19)(20)(21).…”

Recombinant Glycans on an S‐Layer Self‐Assembly Protein: A New Dimension for Nanopatterned Biomaterials

“…[2,4,10] A novel line of development is directed toward the integration of carbohydrate compounds (glycans) into this biomolecular construction kit through co-or post-translational fusion of the carbohydrates to the self-assembly S-layer protein matrix, leading to the production of self-assembled S-layer neoglycoproteins. [11] Considering that glycans are ubiquitous biomolecules, which, in many cases, are key to protein function, [12][13][14] it is evident that glycans are useful means for addressing various questions in the fields of basic and applied research, relating to the areas of biomimetics, drug targeting, vaccine design, [15] or diagnostics. [16,17] Vital cellular functions that are regulated or influenced by glycans include, for instance, recognition, signaling, trafficking, biological half life, and adhesion events; several immunological phenomena are also enabled and enhanced through glycan "signals" on proteins.…”

Preparation and evaluation of immunogenic conjugates ofSalmonella entericaserovar Typhi O-specific polysaccharides with diphtheria toxoid

“…2 Vaccines based on polysaccharide alone fail to induce protective levels of antibodies in young children less than 2 y old and even re-immunization of most polysaccharides does not induce a booster response. 3 Production of conjugate vaccines involves the conjugation of polysaccharide antigen of a particular pathogen with a carrier protein. This conjugation converts the T-cell independent polysaccharide antigen into a T-cell dependent antigen, which results in better immunological response.…”