Pus: the Rodney Dangerfield of immunology

for his catch phrase 'I don't get no respect' , which he used to punctuate monologues throughout an illustrious career. Th e fulcrum of humor on topics such as drinking, sex and marriage, the phrase fi t well the persona of Dangerfi eld. Th is was a man whose appearance dis-respected respect. His eyes bulged, he was nervous and jittery and he constantly tugged at his collar and wiped sweat from his brow. It seemed that, no matter what Dangerfi eld did, respect would keep far from his way. Biological fl uids do not speak (or do stand-up) but, if they did, pus would be the Rodney Dangerfi eld of immunology, defi nitely complaining about its treatment. While arguably one of the most critical expressions of innate immunity-a veritable magic elixir to vanquish infection and decontaminate the most noxious debris-pus per se does not appear to be the focus of many studies. Consider the following statistics. For the year 2010, Medline lists 259 citations with pus as a key word. In contrast, exudate had 412 citations and eff usion had 1,525. I could not fi nd one reference ever published on the pus proteome. Not only is pus uncommonly a research topic but investigators do not seem to want to identify themselves with this fl uid. Who is the world's pus expert? I do not know anyone who has embraced this distinction. Th e situation is not surprising since pus is not the most pleasant material in the world. It is thick, slimy and gooey-indeed, downright yucky. Th e color is disgusting unless you like a vile mélange of yellow, green and brown. And the stuff often stinks. Even though it is readily accessible in the clinic and ward-an easily sampled bonanza for biomarker development and translational research-investigators turn their heads (and noses) away when pus is around. Times may be changing, however, and pus may fi nally be attracting the attention and respect that it deserves. Th e impetus for such change has been the discovery of one of the most ingenious systems for host defense that the immune system deploys. Th is system has been termed NETs, an acronym that stands for neutrophil extracellular traps. In simplest form, NETs represent the DNA from a neutrophil that has been extruded into the extracellular space by a unique mechanism called NETosis. In NETosis, certain activating infl uences can trigger a …