Saturday, November 25, 2006

Neutrophil DNA traps pathogens

drj writes "Most white blood cells are neutrophils, which are small, very short lived (hours-days) cells that are crucial in immune defense. Once triggered, they leave the bloodstream and enter inflamed tissues where they engulf and kill bacteria and fungi with hydrogen peroxide and protein toxins. Now, Brinkmann and colleagues show that stimulated neutrophils also produce DNA-containing fibers that can trap and kill bacteria. They suggest these fibers, which they named neutrophil extracellular traps (NETs), are key mediators of anti-bacterial activity. Dead and dying neutrophils are major constituents of pus, from which DNA (‘nuclein’) was discovered in 1869 by Friedreich Meisher.
PubMed Brinkmann et al. Science. 2004 Mar 5;303(5663):1532-5. Neutrophil extracellular traps kill bacteria"

1 comment:

Anonymous said...

DNA is long, tough, and stringy...

Anybody who has ever prepared DNA in the lab has probably appreciated that its remarkable properties go beyond coding. In addition to being very long (2 m per genome), it is pretty tough (at least in bundles). Applying these physical properties to immune defense seems reasonable.
Do lower organisims have short-lived cells like neutrophils?