Project description:Edema toxin (EdTx), which is a combination of edema factor and a binding moiety (protective antigen), is produced by Bacillus anthracis, the etiological agent of anthrax. EdTx is an adenylyl cyclase enzyme that converts adenosine triphosphate to adenosine-3’,5’-monophosphate, resulting in interstitial edema seen in anthrax patients. We used GeneChip analysis to examine global transcriptional profiles of EdTx-treated RAW 264.7 murine macrophage-like cells at 3 and 6 hr. Keywords: Toxin response
Project description:Purpose: In this work, we evaluated the role of two indicative species, Citrobacter werkmanii (CW) and Escherichia albertii (EA), in the virulence of two DEC pathotypes, Shiga toxin-producing (STEC) and enteroaggregative (EAEC) Escherichia coli. Methods: To determine the effect of supernatant obtained from CW and EA cultures in STEC strain 86-24 and EAEC strain 042 gene expression, a RNA-seq analysis was performed. T84 cells were infected with DEC strains in the presence or absence of supernatant from EA and IL-8 secretion was evaluated. The effect of supernatant from EA on the growth and adherence of STEC and EAEC to T84 cells was also evaluated. Finally, we studied the participation of long polar fimbriae (Lpf) in STEC and plasmid-encoded toxin (Pet) in EAEC during DEC infection in the presence of supernatant from EA. Results: RNA-seq analysis revealed that several virulence factors in STEC and EAEC were up-regulated in the presence of supernatants from CW and EA. Interestingly, an increase in the secretion of IL-8 was observed in T84 cells infected with STEC or EAEC in the presence of a supernatant from EA. Similar results were observed with the supernatants obtained from clinical strains of E. albertii. Supernatant from EA had no effect on the growth of STEC and EAEC, or on the ability of these DEC strains to adhere to intestinal epithelial cells. Finally, we found that Pet toxin in EAEC was up-regulated in the presence of a supernatant from EA. In STEC, using mutant strains for Lpf fimbriae, our data suggested that these fimbriae might be participating in the increase of IL-8 induced by STEC on intestinal epithelial cells in the presence of a supernatant from EA. Conclusion:Supernatant obtained from an indicative species of DEC-positive diarrhea could modulate gene expression in STEC and EAEC, and IL-8 secretion induced by these bacteria. These data provide new insights into the effect of gut microbiota species in the pathogenicity of STEC and EAEC.
Project description:Bacillus anthracis, the causative agent of anthrax, secretes three toxin proteins: protective antigen (PA), lethal factor (LF), and edema factor (EF). PA is a transporter of LF and EF into host cells by receptor-mediated endocytosis. LF is a metalloprotease that cleaves mitogen-activated protein kinase (MAPK) kinases (MKK), while EF is an adenylate cyclase, which converts ATP to cAMP. We used microarrays to decipher the specific gene regulation in edema toxin (ET), the complex of EF and PA, treated mouse bone marrow derived macrophages. Experiment Overall Design: BMDM were treated with 1 mg/ml of ET and the RNAs were purified at 0, 2, and 4h after toxin treatment.
Project description:Bacillus anthracis, the causative agent of anthrax, secretes three toxin proteins: protective antigen (PA), lethal factor (LF), and edema factor (EF). PA is a transporter of LF and EF into host cells by receptor-mediated endocytosis. LF is a metalloprotease that cleaves mitogen-activated protein kinase (MAPK) kinases (MKK), while EF is an adenylate cyclase, which converts ATP to cAMP. We used microarrays to decipher the specific gene regulation in edema toxin (ET), the complex of EF and PA, treated mouse bone marrow derived macrophages. Keywords: Time course
Project description:Shiga toxin type 2 (Stx2) is the main virulence factor produced by Stx-producing Escherichia coli (STEC) responsible for hemorrhagic colitis and the life-threatening sequela hemolytic uremic syndrome.
Project description:Human microvascular endothelial cells (HMVEC) treated with vascular endothelial growth factor (VEGF), Antrhax Edema Toxin (ET), or the Epac activator, 8-pCPT-2'-O-Me-cAMP (8CPT) Human microvascular endothelial cells (HMVEC) were treated with VEGF alone or VEGF in combination with either the the Epac-specific cAMP-mimetic, 8-pCPT-2'-O-Me-cAMP (8CPT), or anthrax edema toxin (ET), an adenylyl cyclase. ET or 8CPT can inhibit VEGF-mediated chemotaxis and angiogenesis. The goal of the study was to identify genes regulated by cAMP production (ET) or by activation of Epac/Rap (8CPT) that may mitigate the effects of VEGF treatment.
2009-08-25 | GSE17777 | GEO
Project description:Shiga toxin E. coli (STEC) from wildlife
Project description:Human microvascular endothelial cells (HMVEC) treated with vascular endothelial growth factor (VEGF), Antrhax Edema Toxin (ET), or the Epac activator, 8-pCPT-2'-O-Me-cAMP (8CPT); Human microvascular endothelial cells (HMVEC) were treated with VEGF alone or VEGF in combination with either the the Epac-specific cAMP-mimetic, 8-pCPT-2'-O-Me-cAMP (8CPT), or anthrax edema toxin (ET), an adenylyl cyclase. ET or 8CPT can inhibit VEGF-mediated chemotaxis and angiogenesis. The goal of the study was to identify genes regulated by cAMP production (ET) or by activation of Epac/Rap (8CPT) that may mitigate the effects of VEGF treatment. Experiment Overall Design: Gene expression was measured 4 hours after treatment with VEGF, VEGF + 8CPT, VEGF + ET or mock treatment. Each sample contained one replicate.
