title: Carbohydrate-based Clostridium difficile vaccines.
abstract: Clostridium difficile is responsible for thousands of deaths each year and a vaccine would be welcomed, especially one that would disrupt bacterial maintenance, colonization and persistence in carriers and convalescent patients. Structural explorations at the University of Guelph (ON, Canada) discovered that C. difficile may express three phosphorylated polysaccharides, named PSI, PSII and PSIII; this review captures our recent efforts to create vaccines based on these glycans, especially PSII, the common antigen that has precipitated immediate attention. The authors describe the design and immunogenicity of vaccines composed of raw polysaccharides and conjugates thereof. So far, it has been observed that anti-PSII antibodies can be raised in farm animals, mice and hamster models; humans and horses carry anti-PSII IgA and IgG antibodies from natural exposure to C. difficile, respectively; phosphate is an indispensable immunogenic epitope and vaccine-induced PSII antibodies recognize PSII on C. difficile outer surface.
authors.affiliation: University of Guelph, Guelph, ON, N1G 2W1, Canada. monteiro@uoguelph.ca
authors.forename: Mario A
authors.initials: MA
authors.lastname: Monteiro
authors.forename: Zuchao
authors.initials: Z
authors.lastname: Ma
authors.forename: Lisa
authors.initials: L
authors.lastname: Bertolo
authors.forename: Yuening
authors.initials: Y
authors.lastname: Jiao
authors.forename: Luis
authors.initials: L
authors.lastname: Arroyo
authors.forename: Douglas
authors.initials: D
authors.lastname: Hodgins
authors.forename: Michael
authors.initials: M
authors.lastname: Mallozzi
authors.forename: Gayatri
authors.initials: G
authors.lastname: Vedantam
authors.forename: Martin
authors.initials: M
authors.lastname: Sagermann
authors.forename: John
authors.initials: J
authors.lastname: Sundsmo
authors.forename: Herbert
authors.initials: H
authors.lastname: Chow
mesh_terms: D000818:Animals; D000829:Animals, Domestic; D000907:Antibodies, Bacterial / Q000097:blood; D001428:Bacterial Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D016360:Clostridioides difficile / Q000276:immunology*; D006224:Cricetinae; D004195:Disease Models, Animal; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D051379:Mice; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D018074:Vaccines, Conjugate / Q000008:administration & dosage / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D001428:Bacterial Vaccines; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D011135:Polysaccharides, Bacterial; D018074:Vaccines, Conjugate