Toll-Like Receptor 5-Dependent Immunogenicity and Protective Efficacy of a Recombinant Fusion Protein Vaccine Containing the Nontoxic Domains of Clostridium difficile Toxins A and B and Salmonella enterica Serovar Typhimurium Flagellin in a Mouse Model of Clostridium difficile Disease

A chimeric protein comprising the glucosyltransferase and cysteine proteinase domains of toxin B and the receptor binding domain of toxin A induces protective immunity againstClostridium difficileinfection in mice and hamsters

“…In particular, RBDs of TcdA and TcdB have been evaluated for their ability to induce protective immunity. 25,[32][33][34] Recent studies have indicated that the N-terminal GT domain of TcdB can serve as an excellent immunogen. 35,36 This notion was initially supported by our recent construction of a chimeric recombinant vaccine against TcdA and TcdB, i.e., cTxAB, in which the original RBD of a full-length TcdB was replaced with the corresponding portion of TcdA.…”

The Prospect for Vaccines to Prevent Clostridium difficile Infection

“…38 The role of flagellin in the activation of TLR-5 may lead to protection against CDI-induced damage. Therefore, it is still unknown whether innate immune responses are, as a whole, beneficial or harmful to the human host.…”

Vaccines againstClostridium difficile

“…With a more traditional approach, the use of RBDs of both toxins were also tested in combination with the immune-adjuvant flagellin of Salmonella typhimurium, with the rationale to stimulate the toll-like receptor 5, 121 known to protect mice against C. difficile colitis. Although the adjuvant activity of flagellin contributed to an enhanced systemic and intestinal IgA response against TcdA, the vaccination was not equally efficient against TcdB; moreover, flagellin did not confer an advantage in the animal model since the protective effect of the toxin domains promoted mice survival from lethal challenge even in absence of adjuvants.…”