By IANS,
Washington : Among the many microbes that target humans, salmonella is perhaps the dodgiest, quietly tricking the immune system into permitting it to gain a foothold.
A new study has discovered just how this virulent, rod-shaped bacterium does this.
The study, by a team of researchers at the University of Rochester, has identified a protein that allows salmonella to maintain a low profile and gain a foothold quietly before the immune system is roused to fight the invader.
“Salmonella is especially equipped with tools to allow it to evade the immune system early on, growing quietly and then really making the host quite ill. Salmonella is trickier than we imagined,” said Jun Sun, leader of the team.
Usually, when a bug invades a human body, it causes an inflammation, which alerts the immune system and gets it to fight the bacteria.
In salmonella’s case, Sun’s team found that a virulent protein known as AvrA dampens the inflammatory response and helps the bacteria avoid the wrath of the immune system and gives the infection crucial time to grow.
“AvrA allows salmonella to make peace with you, buying the bacteria a little time to survive in the body,” said Sun. “That’s bad news for the body, because then the bacteria spreads.
“Bacteria have been evolving for millions of years. That gives them some tricks that perhaps we don’t understand yet,” noted Sun.
The findings of the study have been published in the latest issue of the online journal PloS One.