Clostridium perfringens Enterotoxin Damages the Human Intestine In Vitro (original) (raw)

Effects of Clostridium perfringens Beta-Toxin on the Rabbit Small Intestine and Colon

Infection and Immunity, 2008

Clostridium perfringens type B and type C isolates, which produce beta-toxin (CPB), cause fatal diseases originating in the intestines of humans or livestock. Our previous studies demonstrated that CPB is necessary for type C isolate CN3685 to cause bloody necrotic enteritis in a rabbit ileal loop model and also showed that purified CPB, in the presence of trypsin inhibitor (TI), can reproduce type C pathology in rabbit ileal loops. We report here a more complete characterization of the effects of purified CPB in the rabbit small and large intestines. One microgram of purified CPB, in the presence of TI, was found to be sufficient to cause significant accumulation of hemorrhagic luminal fluid in duodenal, jejunal, or ileal loops treated for 6 h with purified CPB, while no damage was observed in corresponding loops receiving CPB (no TI) or TI alone. In contrast to the CPB sensitivity of the small intestine, the colon was not affected by 6 h of treatment with even 90 g of purified CPB whether or not TI was present. Time course studies showed that purified CPB begins to induce small intestinal damage within 1 h, at which time the duodenum is less damaged than the jejunum or ileum. These observations help to explain why type B and C infections primarily involve the small intestine, establish CPB as a very potent and fast-acting toxin in the small intestines, and confirm a key role for intestinal trypsin as an innate intestinal defense mechanism against CPB-producing C. perfringens isolates.

Evidence for Clostridium perfringens enterotoxin (CPE) inducing a mitogenic and cytokine response in vitro and a cytokine response in vivo

Current microbiology, 1999

We investigated some immunogenic properties of Clostridium perfringens enterotoxin (CPE) in vitro using murine J774A macrophages (M⌽) and in vivo using Swiss Webster (SW) mice. CPE was a potent mitogen in vitro, where cell proliferation increased with CPE concentration. CPE was nonmitogenic when M⌽ were concurrently incubated with CPE and interferon gamma (IFN-␥). M⌽ incubated in the presence of CPE induced the synthesis of interleukin-1 (IL-1), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-␣) and interferon-gamma (IFN-␥), but not interleukin-2 (IL-2). In vivo, CPE induced a pro-inflammatory cytokine response with striking production of IFN-␥, IL-1, and IL-6. Regardless of route of CPE entry, serum cytokine levels generally peaked within 1 h of administration and were maintained for 4-8 h. Although CPE engenders an intense immune response during toxicosis, the toxin does not appear to be a superantigen. Death from CPE-induced shock appears to result from various interrelating immunological mechanisms.

Mapping of functional regions of Clostridium perfringens type A enterotoxin

Infection and immunity, 1992

Studies were conducted to allow construction of an initial map of the structure-versus-function relationship of the Clostridium perfringens type A enterotoxin (CPE). Removal of the N-terminal 25 amino acids of CPE increased the primary cytotoxic effect of CPE but did not affect binding. CPE sequences required for at least four epitopes were also identified.

Clostridium perfringens Type E Virulence Traits Involved in Gut Colonization

PLOS ONE, 2015

Clostridium perfringens type E disease in ruminants has been characterized by hemorrhagic enteritis or sudden death. Although type E isolates are defined by the production of alpha and iota toxin, little is known about the pathogenesis of C. perfringens type E infections. Thus far, the role of iota toxin as a virulence factor is unknown. In this report, iota toxin showed positive effects on adherence and colonization of C. perfringens type E while having negative effect on the adherence of type A cells. In-vitro and in-vivo models suggest that toxinotype E would be particularly adapted to exploit the changes induced by iota toxin in the surface of epithelial cells. In addition, type E strains produce metabolites that affected the growth of potential intra-specific competitors. These results suggest that the alteration of the enterocyte morphology induced by iota toxin concomitantly with the specific increase of type E cell adhesion and the strong intra-specific growth inhibition of other strains could be competitive traits inherent to type E isolates that improve its fitness within the bovine gut environment.

In colon epithelia, Clostridium perfringens enterotoxin causes focal leaks by targeting claudins which are apically accessible due to tight junction derangement

The Journal of Infectious Diseases

Clostridium perfringens enterotoxin (CPE) causes food poisoning and antibiotic-associated diarrhea. It uses some claudin tight junction proteins (eg, claudin-4) as receptors to form Ca 2+-permeable pores in the membrane, damaging epithelial cells in small intestine and colon. We demonstrate that only a subpopulation of colonic enterocytes which are characterized by apical dislocation of claudins are CPE-susceptible. CPE-mediated damage was enhanced if paracellular barrier was impaired by Ca 2+ depletion, proinflammatory cytokine tumor necrosis factor α, or dedifferentiation. Microscopy, Ca 2+ monitoring, and electrophysiological data showed that CPE-mediated cytotoxicity and barrier disruption was limited by extent of CPE-binding. The latter was restricted by accessibility of non-junctional claudin molecules such as claudin-4 at apical membranes. Focal-leaks detected in HT-29/B6 colonic monolayers were verified for native tissue using colon biopsies. These mechanistic findings indicate how CPE-mediated effects may turn from self-limiting diarrhea into severe clinical manifestation such as colonic necrosis-if intestinal barrier dysfunction, eg, during inflammation facilitates claudin accessibility. Keywords. claudin; Clostridium perfringens enterotoxin; HT-29/B6 cells; pore-forming toxin; tight junction. METHODS Plasmids For expression as N-terminal 6xHis-fusion, CPE cDNA was subcloned from vector pCpG-optCPE [24] into pTrcHis-TOPO using pTrcHis-TOPO TA kit (Invitrogen). Site-directed mutagenesis to generate CPE-Y306A/L315A was performed as described [25].

Effects of Clostridium perfringens iota toxin in the small intestine of mice

Anaerobe, 2017

Iota toxin is a binary toxin solely produced by Clostridium perfringens type E strains, and is structurally related to CDT from C. difficile and CST from C. spiroforme. As type E causes hemorrhagic enteritis in cattle, it is usually assumed that associated diseases are mediated by iota toxin, although evidence in this regard has not been provided. In the present report, iota toxin intestinal effects were evaluated in vivo using a mouse model. Histological damage was observed in ileal loops treated with purified iota toxin after 4 h of incubation. Luminal iota toxin induced fluid accumulation in the small intestine in a dose dependent manner, as determined by the enteropooling and the intestinal loop assays. None of these changes were observed in the large intestine. These results suggest that C. perfringens iota toxin alters intestinal permeability, predominantly by inducing necrosis and degenerative changes in the mucosal epithelium of the small intestine, as well as changes in int...

Beta toxin is essential for the intestinal virulence of Clostridium perfringens type C disease isolate CN3685 in a rabbit ileal loop model: Clostridium perfringens type C isolate CN3685 intestinal virulence

Molecular Microbiology, 2007

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. , 15-30 agarose gel was then transferred onto a nylon membrane and hybridized with an intron-specific DIG-labelled probe. Lane 1: Wild-type CN3685; lane 2: BMC100; lane 3: BMC101; lane 4: BMC102; and lane 5: BMC103.