By Beth Mole
DENVER — With the flip of a cellular switch, reactive molecules in air pollution can turn immune responses in the lungs topsy-turvy. When those reactive molecules fill baby mouse lungs, they can open the door to severe infections as well as set the stage for asthma later in life, researchers reported March 23 at the national meeting of the American Chemical Society.
The reactive molecules can damage cellular components such as DNA, proteins and lipids, causing oxidative stress and switching on an immune-regulating protein called aryl hydrocarbon receptor, or Ahr. In the lungs of infant mice, the reactive molecules dampened immune defenses, leaving the pups vulnerable to viral infections such as the flu. Such exposure also led mice pups to grow up to have hyperimmune responses, leading to severe asthma.