Protective/reparative cytokines are suppressed at high injury severity in human trauma

Background: Trauma elicits a complex inflammatory response that, among multiple presenting factors, is greatly impacted by the magnitude of injury severity. Herein, we compared the changes in circulating levels of mediators with known proinflammatory roles to those with known protective/reparative actions as a function of injury severity in injured humans. Methods: Clinical and biobank data were obtained from 472 (trauma database-1 (TD-1), University of Pittsburgh) and 89 (trauma database-2 (TD-2), Indiana University) trauma patients admitted to the intensive care unit (ICU) and who survived to discharge. Injury severity was estimated based on the Injury Severity Score (ISS), and this was used as both a continuous variable and for the purpose of grouping patients into severity-based cohorts. Samples within the first 24 hours were obtained from all patients and then daily up to day 7 postinjury in TD-1. Sixteen cytokines were assayed using Luminex and were analyzed using two-way analysis of variance (p