Scientists have revealed yet another way in which the bacterium that causes anthrax disarms the immune system.
The microbe, Bacillus anthracis, produces a molecular complex that's called lethal toxin known to interrupt a cascade of signals inside macrophages, the immune cells that envelop and destroy bacteria (SN: 5/9/98, p. 299). This interference kills the macrophages.
The toxin also interrupts the same signaling cascade in dendritic cells, another class of immune cells, Bali Pulendran of the Emory Vaccine Research Center in Atlanta and his coworkers report in the July 17 Nature. Dendritic cells are crucial to an immune response since they alert antibody-producing cells and other protective cells to the presence of dangerous microbes.