A Phalipon

..These results are the first example of immunogenic mimicry of carbohydrates by phage-displayed peptides, and indicate a new strategy of selection of immunogens for the development of anti-polysaccharide vaccines...

..This profile is likely to impact on the nature and quality of the adaptive response, which is dominated by humoral protection at the mucosal level...

..Therefore, binding of IgA(d/p) to SC during the course of SIgA-mediated mucosal response constitutes a crucial step in achieving efficient protection of the epithelial barrier by immune exclusion...

..The escape strategies, the possible direct effect of Shigella on B and T lymphocytes, their impact on the development of adaptive immunity, and how they may help explain the limited protection induced by natural infection are discussed...

..A pentadecasaccharide representing three biological repeating units was identified as a potential candidate for further development of a chemically defined glycoconjugate vaccine against S. flexneri 2a infection...

..Our results have implications for vaccine development because they suggest that a minimum of two RUs of synthetic serotype 2a oligosaccharide is required for optimal mimicry of O-Ag epitopes...

..flexneri live attenuated strains as mucosal vectors for foreign epitopes...

..This synthetic carbohydrate-based conjugate may be a candidate for a SF2a vaccine...

..In contrast, 5-day-old mice inoculated with either the invasive or the non-invasive strain were not infected. We have thus established a mouse model that is suitable for the study of the pathogenesis of intestinal Shigella infection...

..Thus, intracellular neutralization by dIgA limits the acute local inflammation induced by proinflammatory pathogen-associated molecular patterns such as LPS...

..Here, we describe a new diagnostic test for rapid detection, in stool, at the bedside of patients, of Shigella flexneri 2a, the most predominant agent of the endemic form of the disease...

..More basic research is also required to improve what we can still consider as first-generation vaccines, and to explore possible new paradigms including the search for cross-protective antigens...

..It is based on the use of the trichloroacetimidate chemistry. The target branched oligosaccharide was designed to probe the recognition at the molecular level of the natural polysaccharide by protective monoclonal antibodies...

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..Therefore, MxiG and possibly proteins secreted by the Mxi-Spa translocation are involved not only in entry but also in spread of Shigella between epithelial cells...

..This newly made available system provides a new contribution to the understanding of the molecular mimicry of complex polysaccharides by peptides and short oligosaccharides...

..The models that are in agreement with NMR data adopt right-handed 3-fold helical structures in which the branched glucosyl residue points outwards...

..The multiple mechanisms that they are involved in make pIgR and SC instrumental to mucosal immunity...

..These findings bring new insights into the adaptive immune response to Shigella infection and highlight the importance of pathogen-specific Th17 cell immunity for secondary immune protection...

..Thus, the combination of acylation state and host genetics may significantly impact vaccine immunogenicity and/or efficacy, whether LPS is an integral component of a whole organism vaccine or included as an adjuvant...

..Because mice are naturally resistant to shigellosis, there is no mouse model that mimics human disease. We explore the susceptibility of intestinal flora-depleted mice to shigellosis after intragastric infection with Shigella strains...

..The rapid death of DC during the early stages of shigellosis is likely to have adverse consequences for generation of adaptive immunity...

..flexneri infection through amplification of an inflammatory response. This cellular lymphocyte redundancy assures IFN-gamma production, which is central to innate immunity against Shigella infection...

..These findings demonstrate that the Shigella T3S apparatus can deliver biologically active cytokines in vivo, thus opening new avenues for the use of attenuated bacteria to deliver proteins for immunomodulation or gene therapy purposes...