Serum ST2 as a potential prognostic biomarker for traumatic brain injury

Background: ST2, a receptor of interleukin-33, is involved in inflammation. We discerned the relationship between serum soluble ST2 (sST2) concentrations, inflammation, severity and prognosis following traumatic brain injury (TBI). Methods: We measured serum 5ST2, interleukin-6, tumor necrosis factor-alpha, C-reactive protein, myelin basic protein, glial fibrillary astrocyte protein, S100B, neuron-specific enolase, phosphorylated axonal neurofilament subunit H, Tau and ubiquitin carboxyl-terminal hydrolase L1 concentrations in 106 healthy controls and 106 severe TBI patients. We recorded long-term prognosis (i.e., 6-month mortality and functional outcome) and in hospital major adverse events, including in-hospital mortality, acute lung injury, acute traumatic coagulopathy, progressive hemorrhagic injury and posttraumatic cerebral infarction. Results: 5ST2 concentrations were significantly higher in patients than in controls and were significantly correlated with Glasgow coma scale (GCS) score and the preceding biomarkers concentrations. Serum sST2 was an independent prognostic predictor and its predictive ability significantly exceeded those of serum interleukin-6, tumor necrosis factor-alpha and C-reactive protein concentrations and was similar to those of GCS scores and serum concentrations of other remaining biomarkers. Moreover, 5ST2 concentrations significantly improved predictive ability of GCS score. Conclusion: Increased serum sST2 concentrations are significantly related to inflammation, severity and prognosis, substantialized ST2 as a potential prognostic biomarker for TBI.