Basic science for the clinician 59: polymorphonuclear cells: mechanisms in human defense and in the pathogenesis of...

When I learned about polymorphonuclear neutrophils (PMNs) in medical school, they were presented as pretty much 1-trick ponies: PMNs were phagocytes with no intrinsic specificity; their only specificity was supplied by the Fcγ receptors on their surfaces and that would then be the specificity of the bound immunoglobulin G, nothing intrinsic to the PMN. My, how simple life was in those days! And how wrong! Turns out, these circulating cells are involved in bridging the innate immune system and the acquired immune response in some very interesting ways and may play a crucial role in the immunopathogenesis of some of "our" diseases. Polymorphonuclear neutrophils are often underappreciated as drivers of inflammatory diseases, which is why I think it is time for us to turn our attention to this underappreciated component of the immune response.