An
anthrax infection can be fatal even when the infectious agent is no longer
detected. Research carried out at EPFL reveals the way its lethal factor
manages to turn invisible to the immune system.
The
bacterium responsible for anthrax develops a strategy reminiscent of the Trojan
horse tale. Its pathogenic factor is able to penetrate inside a cell in such a
way that it becomes completely invisible to both the immune system and medical
analysis. Furthermore, it manages to exit the cell several days later, and then
it continues to poison other cells.
In
a new study, researchers focused in the way the anthrax toxin was able to get
inside the cell. Composed of two elements -- a "protective antigen"
and a "lethal factor," the toxin does not merely create a passage
across the cellular membrane. Instead, it introduces itself by endocytosis, a
process by means of which the pathogen is "swallowed" by the cell. Once
inside the cell, anthrax's lethal factor is sheltered by the cell's membrane,
forming an "endosome," in which it can wait for several days. Then,
it can either be released inside the cell, causing it to malfunction, or it can
be released towards the external environment inside small vesicles -- called
exosomes -- and get into another cell.
For
further details, refer to the following paper:
Posted by Tim Sandle
No comments:
Post a Comment
Pharmaceutical Microbiology Resources