The WAP protein Trappin-2/Elafin: A handyman in the regulation of inflammatory and immune responses

Trappin-2/Elafin is a potent serine protease inhibitor which prevents excessive damage under inflammatory status. This alarm-antiprotease is locally expressed by epithelial cells and immune cells such as macrophages and gamma delta T cells. It has also been proven to modulate a wide range of parameters that are critical for the inflammation process like modulating the NF kappa B pathway, cytokine secretion and cell recruitment. In addition, Trappin-2/Elafin was shown to possess anti-microbial properties against different classes of pathogens including viruses, fungi and bacteria. Studies also linked Trappin-2/Elafin to either susceptibility or protection against inflammatory disease and infections, even though the mechanisms remains poorly understood. This review will discuss some of the pleiotropic effects displayed by Trappin-2/Elafin, and the properties that could be used to prevent infection or to protect against inflammation. (C) 2012 Published by Elsevier Ltd.