SipD and IpaD induce a cross-protection against < i > Shigella < /i > and < i > Salmonella < /i > infections

by Bakhos Jneid, Audrey Rouaix, C écile Féraudet-Tarisse, Stéphanie SimonSalmonella andShigella species are food- and water-borne pathogens that are responsible for enteric infections in both humans and animals and are still the major cause of morbidity and mortality in the emerging countries. The existence of multipleSalmonella andShigella serotypes as well as the emergence of strains resistant to antibiotics require the development of broadly protective therapies. Those bacteria utilize a Type III Secretion System (T3SS), necessary for their pathogenicity. The structural proteins composing the T3SS are common to all virulentSalmonella andShigella spp., particularly the needle-tip proteins SipD (Salmonella) and IpaD (Shigella). We investigated the immunogenicity and protective efficacy of SipD and IpaD administered by intranasal and intragastric routes, in a mouse model ofSalmonella enterica serotype Typhimurium (S. Typhimurium) intestinal challenge. Robust IgG (in all immunization routes) and IgA (in intranasal and oral immunization routes) antibody responses were induced against both proteins. Mice immunized with SipD or IpaD were protected against lethal intestinal challenge withS. Typhimurium orShigella flexneri (100 Lethal Dose 50%). We have shown that SipD and IpaD are able to induce a cross-protection in a murine model of infection bySalmonella andShigella. We provide the first demonstration thatSalmonella andShigella T3SS SipD and IpaD are promising antigens for t...
Source: PLoS Neglected Tropical Diseases - Category: Tropical Medicine Authors: Source Type: research