title: From Immunologically Archaic to Neoteric Glycovaccines.
abstract: Polysaccharides (PS) are present in the outermost surface of bacteria and readily come in contact with immune cells. They interact with specific antibodies, which in turn confer protection from infections. Vaccines with PS from pneumococci, meningococci,Haemophilus influenzaetype b, andSalmonella typhimay be protective, although with the important constraint of failing to generate permanent immunological memory. This limitation has in part been circumvented by conjugating glycovaccines to proteins that stimulate T helper cells and facilitate the establishment of immunological memory. Currently, protection evoked by conjugated PS vaccines lasts for a few years. The same approach failed with PS from staphylococci,Streptococcus agalactiae, andKlebsiella. All those germs cause severe infections in humans and often develop resistance to antibiotic therapy. Thereby, prevention is of increasing importance to better control outbreaks. As only 23 of more than 90 pneumococcal serotypes and 4 of 13 clinically relevantNeisseria meningitidisserogroups are covered by available vaccines there is still tremendous clinical need for PS vaccines. This review focuses on glycovaccines and the immunological mechanisms for their success or failure. We discuss recent advances that may facilitate generation of high affinity anti-PS antibodies and confer specific immunity and long-lasting protection.
authors.affiliation: BIOSS Centre for Biological Signalling Studies, University of Freiburg, Schaenzlestrasse 18, 79104 Freiburg, Germany. marco.cavallari@bioss.uni-freiburg.de.
authors.forename: Marco
authors.initials: M
authors.lastname: Cavallari
authors.affiliation: Experimental Immunology, Department of Biomedicine, University of Basel, Hebelstrasse 20, 4031 Basel, Switzerland. gennaro.delibero@unibas.ch.
authors.forename: Gennaro
authors.initials: G
authors.lastname: De Libero
keywords: T cell help; conjugate; immunosenescence; polysaccharide; serotype; vaccine