How anthrax enters cells revealed  

Microbiologists at the University of Alabama at Birmingham (UAB) have achieved a major breakthrough in uncovering a biological 'gateway' that anthrax uses to enter healthy cells.

The researchers say that anthrax spores enter the cell through a receptor called Mac-1, which sits on the surface of certain cells.

This is the first time that a team of researchers has shown exactly how the bacteria get inside cells. Previous studies had focused on what happens after anthrax spores enter the body and wreak havoc.

UAB microbiologists insist that unravelling this biological gateway is a milestone in the ongoing efforts to protect humans from bio-terrorism and biological warfare. This discovery may pave the way for new drugs and vaccines to fight or prevent anthrax infection, besides advancing the understanding of bacterial infection, they add.

"We know anthrax infection can occur in wild and domestic animals, but in humans this disease is extremely rare and very dangerous. It is a bio-weapon," said John Kearney, a professor in the UAB Department of Microbiology, and co-author on the study.

"This study reveals the biological paradigm that makes the anthrax spore clever enough to target the Mac-1 receptor, and use this entry point to boost its lethality," he added.

During the course of study, the researchers worked under strict bio-safe conditions to infect cultures of cells and laboratory-bred mice with a strain of anthrax.

Upon having a look at the infection rates, and making other observations, the researchers became convinced that anthrax relies on Mac-1 to do its damage inside healthy cells.

"By showing how anthrax spores recognize Mac-1 receptors, this discovery points toward a precise entry point which B. anthracis uses to proliferate and trigger lethal consequences," said Claudia Oliva and Melissa Swiecki, both researchers in the UAB Department of Microbiology, and co-lead authors on the study.

The study, funded by the National Institutes of Health, has been published in the online version of the journal Proceedings of the National Academy of Sciences.