title: Rethinking the role of alpha toxin in Clostridium perfringens-associated enteric diseases: a review on bovine necro-haemorrhagic enteritis.
abstract: Bovine necro-haemorrhagic enteritis is an economically important disease caused by Clostridium perfringens type A strains. The disease mainly affects calves under intensive rearing conditions and is characterized by sudden death associated with small intestinal haemorrhage, necrosis and mucosal neutrophil infiltration. The common assumption that, when causing intestinal disease, C. perfringens relies upon specific, plasmid-encoded toxins, was recently challenged by the finding that alpha toxin, which is produced by all C. perfringens strains, is essential for necro-haemorrhagic enteritis. In addition to alpha toxin, other C. perfringens toxins and/or enzymes might contribute to the pathogenesis of necro-haemorrhagic enteritis. These additional virulence factors might contribute to breakdown of the protective mucus layer during initial stage of pathogenesis, after which alpha toxin, either or not in synergy with other toxins such as perfringolysin O, can act on the mucosal tissue. Furthermore, alpha toxin alone does not cause intestinal necrosis, indicating that other virulence factors might be needed to cause the extensive tissue necrosis observed in necro-haemorrhagic enteritis. This review summarizes recent research that has increased our understanding of the pathogenesis of bovine necro-haemorrhagic enteritis and provides information that is indispensable for the development of novel control strategies, including vaccines.
authors.affiliation: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820, Merelbeke, Belgium.
authors.forename: Evy
authors.initials: E
authors.lastname: Goossens
authors.affiliation: Department of Large Animal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820, Merelbeke, Belgium.
authors.forename: Bonnie R
authors.initials: BR
authors.lastname: Valgaeren
authors.affiliation: Department of Large Animal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820, Merelbeke, Belgium.
authors.forename: Bart
authors.initials: B
authors.lastname: Pardon
authors.affiliation: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820, Merelbeke, Belgium.
authors.forename: Freddy
authors.initials: F
authors.lastname: Haesebrouck
authors.affiliation: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820, Merelbeke, Belgium.
authors.forename: Richard
authors.initials: R
authors.lastname: Ducatelle
authors.affiliation: Department of Large Animal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820, Merelbeke, Belgium.
authors.forename: Piet R
authors.initials: PR
authors.lastname: Deprez
authors.affiliation: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820, Merelbeke, Belgium. Filip.VanImmerseel@UGent.be.
authors.forename: Filip
authors.initials: F
authors.lastname: Van Immerseel
mesh_terms: D000818:Animals; D001427:Bacterial Toxins; D002135:Calcium-Binding Proteins / Q000502:physiology*; D002417:Cattle / Q000382:microbiology; D002418:Cattle Diseases / Q000382:microbiology*; D003016:Clostridium perfringens; D004751:Enteritis / Q000382:microbiology / Q000662:veterinary*; D005738:Gas Gangrene / Q000382:microbiology / Q000662:veterinary*; D010738:Type C Phospholipases / Q000502:physiology*
chemical_list: D001427:Bacterial Toxins; D002135:Calcium-Binding Proteins; D010738:Type C Phospholipases; C040649:alpha toxin, Clostridium perfringens