ABSTRACT
Background: Endothelial injury and coagulation activation are prominent axis in coronavirus disease 19 (COVID-19) pathogenesis. However, only few studies have compared profiles of biomarkers of coagulopathy and endotheliopathy with regard to the initial severity of COVID-19 and the time course of the disease. Aim(s): The main objective of our study is to point profiles of biomarkers of coagulopathy and endotheliopathy associated with initial severity of COVID-19 and the time course of the disease. Method(s): In a prospective longitudinal study, we explored coagulation and endothelial function biomarkers at admission, at day 3 and at day 7 in two cohorts of severe and moderate COVID-19 patients and according to outcome. Result(s): We found that D-dimers, free tissue factor pathway inhibition (TFPI) and extracellular vesicles -tissue factor (EV-TF) at admission were associated with disease severity. Concerning outcome, TFPI, EV-TF and von Willebrand factor antigen (VWF)/ADAMTS13 ratio at admission, at day 3 and at day 7 were associated with not favorable outcome defined as the onset of death or need of invasive mechanical ventilation. TFPI with a cut-off value of 37.5 ng/ml had 87% sensitivity and 94% and specificity and EV-TF with a cut-off value of 13 fM had 87% sensitivity and 83% specificity. ROC curves analysis for severe outcome was significant with AUC = 0.90 for TFPI and AUC = 0.88 for EV-TF (p < 0.001 for both). Conclusion(s): We found a specific profile of specialized biomarkers of coagulopathy and endotheliopathy associated with severe form of COVID-19 and not favorable outcome. We identified free TFPI and EV-TF of potential interest to stratify patient's risk or to design specific treatment targeting coagulation pathways. Additional studies are warranted to confirm our results and study the interaction between these biomarkers' values and anticoagulation treatment. (Table Presented).
ABSTRACT
Background: Neutrophils Extracellular Traps (NETs) are emerging biomarkers for their key role in immunothrombosis, including in the context of the recent COVID-19 epidemic. Aims: With the aim of characterizing novel molecular determinants associated with the inter individual variability of NET plasma levels, NETs were measured using a MPO-DNA ELISA assay in 657 participants of the FARIVE study, a French case-control study (372-285) for venous thrombosis. FARIVE participants were typed for genome wide polymorphisms using an Illumina DNA array. Methods: Using a compound poisson-gamma modeling of the NETs distribution characterized by a mixture of excess of 0 values and of positive values, a genome wide association analysis of 8,866,687 imputed polymorphisms was performed. Results: The analysis revealed a significant association peak ( P = 1.7 × 10-8 ) on chromosome 21q21.3. Carriers of the A allele at the lead polymorphism (rs57502213) exhibited increased NETs levels (β=+0.97 ± 0.16) than non carriers, homogeneously in VTE cases (β=+1.20 ± 0.21, N = 372) and in controls (β=+0.73 ± 0.25, N = 285). This polymorphism explained ∼2% of the variability of NETs plasma levels. Rs57502213 maps to microRNA MIR155HG but exhibits very strong linkage disequilibrium with several others polymorphisms covering the MRPL29, JAM2, GABPA and APP genes. Interestingly, GABPA codes for a transcription factor that has been demonstrated in vitro to play a role in the nuclear maturation of neutrophils from which NETs are derived, while APP has been demonstrated to control NET formation in mice. Conclusions: To our knowledge, this work is the first genome-wide association study on NETs and provides the first epidemiologic evidence that the chr21q21.3 locus participates to the regulation of NETs in humans. The association that we observed deserves to be further validated in independent samples (a call will be launched during the ISTH presentation to encourage collaboration) and further investigations will be needed to fine map the genetic regulation of NETs at this locus.