title: Beta toxin is essential for the intestinal virulence of Clostridium perfringens type C disease isolate CN3685 in a rabbit ileal loop model.
abstract: Clostridium perfringens type C isolates, which cause enteritis necroticans in humans and enteritis and enterotoxaemias of domestic animals, typically produce (at minimum) beta toxin (CPB), alpha toxin (CPA) and perfringolysin O (PFO) during log-phase growth. To assist development of improved vaccines and therapeutics, we evaluated the contribution of these three toxins to the intestinal virulence of type C disease isolate CN3685. Similar to natural type C infection, log-phase vegetative cultures of wild-type CN3685 caused haemorrhagic necrotizing enteritis in rabbit ileal loops. When isogenic toxin null mutants were prepared using TargeTron technology, even a double cpa/pfoA null mutant of CN3685 remained virulent in ileal loops. However, two independent cpb null mutants were completely attenuated for virulence in this animal model. Complementation of a cpb mutant restored its CPB production and intestinal virulence. Additionally, pre-incubation of wild-type CN3685 with a CPB-neutralizing monoclonal antibody rendered the strain avirulent for causing intestinal pathology. Finally, highly purified CPB reproduced the intestinal damage of wild-type CN3685 and that damage was prevented by pre-incubating purified CPB with a CPB monoclonal antibody. These results indicate that CPB is both required and sufficient for CN3685-induced enteric pathology, supporting a key role for this toxin in type C intestinal pathogenesis.
authors: Department of Molecular Genetics and Biochemistry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
authors: Sameera
authors: S
authors: Sayeed
authors: Francisco A
authors: FA
authors: Uzal
authors: Derek J
authors: DJ
authors: Fisher
authors: Juliann
authors: J
authors: Saputo
authors: Jorge E
authors: JE
authors: Vidal
authors: Yue
authors: Y
authors: Chen
authors: Phalguni
authors: P
authors: Gupta
authors: Julian I
authors: JI
authors: Rood
authors: Bruce A
authors: BA
authors: McClane
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000276:immunology; D000992:Antitoxins / Q000276:immunology; D001427:Bacterial Toxins / Q000235:genetics / Q000276:immunology / Q000378:metabolism* / Q000633:toxicity; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism; D003015:Clostridium Infections / Q000382:microbiology / Q000662:veterinary*; D003016:Clostridium perfringens / Q000145:classification / Q000276:immunology / Q000472:pathogenicity*; D004195:Disease Models, Animal; D005260:Female; D005838:Genotype; D006460:Hemolysin Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007077:Ileal Diseases / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D007082:Ileum / Q000382:microbiology / Q000473:pathology; D008297:Male; D016254:Mutagenesis, Insertional; D010641:Phenotype; D011817:Rabbits; D012757:Sheep Diseases / Q000382:microbiology; D010738:Type C Phospholipases / Q000235:genetics / Q000378:metabolism; D037521:Virulence Factors / Q000378:metabolism
chemical_list: D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D000992:Antitoxins; D001427:Bacterial Toxins; C031884:CPB protein, Clostridium perfringens; D002135:Calcium-Binding Proteins; D006460:Hemolysin Proteins; D037521:Virulence Factors; C020452:Clostridium perfringens theta-toxin; D010738:Type C Phospholipases; C040649:alpha toxin, Clostridium perfringens