COLUMBUS, Ohio, Oct. 2 (UPI) -- U.S. researchers have determined that Mycobacterium tuberculosis has learned through evolution to coat itself with a sugar called mannose.
This sugar makes the bacterium attractive to cells in the lungs that are looking to clean up and discard unwanted sugar in the body. Those lung cells absorb the TB bacteria, giving the infecting bacteria a place to live for the long term, Ohio State University researchers said.
"The bug sugarcoats itself and creates this magical interaction that allows it to slip by the immune system," Larry Schlesinger said in a statement. "TB has evolved in humans. We're the reservoir. It has had centuries to develop a sophisticated way to deal with its encounter with the human, and the lung is the special portal of entry."
Schlesinger said his most recent discovery -- two strains of TB bacteria that do not show these signs of adaptation -- suggests that some strains of TB bacteria can be tied to specific regions of the world based on specific ways in which they interact with the human immune system.
Schlesinger reported the findings online in the Journal of Biological Chemistry and at the First International Congress "Mycobacteria: A Challenge for the 21st Century" in Bogota.