PROJECT SUMMARY/ABSTRACT Trauma-induced acute respiratory dysfunction syndrome (ARDS) is a deadly condition in which lung failure results from a traumatic injury to another part of the body. Recently, several studies have established a link between circulating histones and lung failure. Traumatic injuries cause a massive amount of cell death, resulting in the release of high concentrations of histones into circulation, which can directly lead to ARDS, as histones damage the lungs. In addition, circulating histones exacerbate exaggerated pro- and anti- inflammatory responses that also result in damage to the lungs and other organs. Identification and quantification of trauma-triggered circulating histones would provide an approach to assess the risk of ARDS, which could enable life-saving therapies before a patient develops ARDS. Diagnostic solutions to provide early detection of histones following trauma should be portable and rapid in order to assess the patient soon after the injury occurs. Currently, however, there are no portable and rapid approaches that enable detection of circulating histones to assess a trauma patient’s risk of developing ARDS. Our goal is to develop a diagnostic tool that is capable of quantitatively assessing the risk of trauma-induced ARDS at the point of care. This may include at the point of injury, in the transport vehicle to a trauma center, in the Emergency Department (ED), or in the operating room (OR). We have invented a Portable Histone Assay Technology (PHAST) that can quantify circulating histones directly from whole blood within 30 minutes. .