Yudin, Nikoli

ABSTRACT Background: Neutrophil extracellular traps (NETs), and its formation and release, known as NETosis, may play a role in the initiation of thrombin generation (TG) in trauma. The objective of this study was to assess whether trauma patients, who develop symptomatic venous thromboembolism (VTE), have increased levels of plasma citrullinated histone H3 (CitH3) and accelerated TG kinetics. Methods: Patients presenting to a level I trauma center as trauma activations had samples collected within 12 h of time of injury, alongside healthy volunteers (HV). CitH3 was measured by enzyme-linked immunosorbent assay, and TG data were measured using a TG analyzer, comparing results between patients developing symptomatic VTE versus those who did not, within 90 days of injury. Data were expressed as median and quartiles (Q1, Q3), and tested using Wilcoxon rank-sum or Fisher’s exact test, or 1-sample test of Spearman’s correlation, P < 0.05 considered significant. Results: 39 trauma patient samples were analyzed (10 with and 29 without VTE), and compared to 15 HV samples. CitH3 levels in patients who developed VTE were significantly greater as compared to those who did not (12.8 ng/mL [7.1, 30.8]; 3.0 ng/mL [1.8,6.8], P = 0.024), with levels in both groups greater compared to HV (1.2 [0.3, 4.1], P = 0.003, P = 0.012), respectively. TG profiles were accelerated in patients developing VTE, with differences in peak height (337.6 nM [304.4, 356.0]; 231.8 nM [180.2, 281.8], P = 0.008), endogenous thrombin potential (1718.5 nM*min [1,500, 1794]; 1208.5 nM*min [1,072, 1,417], P = 0.003) and velocity index (213.2 nM/min [162.3, 260.5]; 124.3 nM/min [93.2, 223.1], P = 0.03), respectively. Conclusion: Trauma patients developing VTE exhibit increased NETosis, measured by increased CitH3 levels and accelerated TG early after injury, outlining an area for further understanding VTE after trauma.

ABSTRACT Background: Inorganic polyphosphate (polyP) is a procoagulant polyanion. We assessed the impact of polyP inhibition on thrombin generation after trauma using the novel polyP antagonists, macromolecular polyanion inhibitor 8 (MPI 8), and universal heparin reversal agent 8 (UHRA-8). Methods: Plasma thrombin generation (calibrated automated thrombogram, CAT), in 56 trauma patients and 39 controls +/− MPI 8 and UHRA-8 (50 μg/mL), was expressed as lag time (LT, minutes), peak height (PH, nM), and time to peak (ttPeak, minutes), with change in LT (ΔLT) and change in ttPeak (ΔttPeak) quantified. Results expressed in median and quartiles [Q1, Q3], Wilcoxon matched-pairs testing, P < 0.05 significant. Results: Trauma patients had greater baseline PH than controls (182.9 [121.0, 255.2]; 120.5 [62.1, 174.8], P < 0.001). MPI 8 treatment prolonged LT and ttPeak in trauma (7.20 [5.88, 8.75]; 6.46 [5.45, 8.93], P = 0.020; 11.28 [8.96, 13.14]; 11.00 [8.95, 12.94], P = 0.029) and controls (7.67 [6.67, 10.50]; 6.33 [5.33, 8.00], P < 0.001; 13.33 [11.67, 15.33]; 11.67 [10.33, 13.33], P < 0.001). UHRA-8 treatment prolonged LT and ttPeak and decreased PH in trauma (9.09 [7.45, 11.33]; 6.46 [5.45, 8.93]; 14.02 [11.78, 17.08]; 11.00 [8.95, 12.94]; 117.4 [74.5, 178.6]; 182.9 [121.0, 255.2]) and controls (9.83 [8.00, 12.33]; 6.33 [5.33, 8.00]; 16.67 [14.33, 20.00]; 11.67 [10.33, 13.33]; 55.3 [30.2, 95.9]; 120.5 [62.1, 174.8]), all P < 0.001. Inhibitor effects were greater for controls (greater ΔLT and ΔttPeak for both inhibitors, P < 0.001). Conclusion: PolyP inhibition attenuates thrombin generation, though to a lesser degree in trauma than in controls, suggesting that polyP contributes to accelerated thrombin generation after trauma.