Mitogen-Activated Protein Kinase Assays

Polymorphonuclear neutrophils (PMN) play an essential role in host defense against bacteria and fungi through coordinated responses such as adhesion, migration, phagocytosis, secretion, and activation of the NADPH oxidase. The mitogen-activated protein kinases (MAPKs) and their activation kinase cascades, which transduce signals from the plasma membrane to the cytosol and nucleus, are an integral part of signaling pathways involved in many cellular responses. PMN express several members of the MAPK family that have been shown, mainly through the use of pharmacological inhibitors, to mediate the cellular activities triggered by a variety of extracellular agonists. Methods to determine MAPK activation have been greatly simplified with the availability of antibodies raised to active MAPKs. The recent development of novel inhibitors for the MAPK pathways may further our understanding of their role in neutrophil function.