Bacillus anthracis lethal toxin induces TNF-α–independent hypoxia-mediated toxicity in mice

Toxin-induced resistance in Bacillus anthracis lethal toxin-treated macrophages.

In the current study, we show that macrophages adaptively resist anthrax lethal toxin (LT) through a toxin-activated process termed toxin-induced resistance (TIR). TIR was triggered by pretreatment of RAW 264.7 or J774A.1 macrophages with a low dose of LT for at least 6 h, which resulted in resistance to high doses of LT for 96 h. Activation of TIR required functional toxin, because LT subunits...

Bacillus anthracis lethal toxin reduces human alveolar epithelial barrier function.

The lung is the site of entry for Bacillus anthracis in inhalation anthrax, the deadliest form of the disease. Bacillus anthracis produces virulence toxins required for disease. Alveolar macrophages were considered the primary target of the Bacillus anthracis virulence factor lethal toxin because lethal toxin inhibits mouse macrophages through cleavage of MEK signaling pathway components, but w...

Human Alveolar Epithelial Barrier Function Bacillus anthracis Lethal Toxin Reduces

Published Ahead of Print 1 October 2012. 2012, 80(12):4374. DOI: 10.1128/IAI.01011-12. Infect. Immun. Patrick Metcalf Burian, Jimmy Dale Ballard, Armin Braun and Jordan Mark Coggeshall, Shanjana Awasthi, Florea Lupu, Dennis Prenzler, Katherina Sewald, Daniel M. Williams, Kenneth Silasi-Mansat, Vijay Ramani, Tibor Zoltan Veres, Frauke Booth, Vineet Indrajit Patel, Ryan A. Zander, Robert Marybeth...

Lethal Toxin Bacillus anthracis to Resistance of Human Alveolar Macrophages

Evidence for plasmid-mediated toxin production in Bacillus anthracis.

Large-molecular-weight plasmids were isolated from virulent and avirulent strains of Bacillus anthracis. Each strain contained a single plasmid species unique from the others with respect to molecular weight. Bacterial strains were cured of their resident extrachromosomal gene pools by sequential passage of cultures at 42.5 degrees C. Coincidental to the curing of plasmids was a loss of detecta...