Exploration of novel mechanisms and biomarkers for venous thromboembolism : a genetics and proteomics study

Background: Venous thromboembolism (VTE) contributes to a large health burden and incidence increases exponentially with age. ~25% patients will experience a recurrent event and there is a 2-fold risk for death in the following years. Risk prediction remains a challenge. Aims to: Investigate a presumed overlap between cardiovascular disease and VTE. Expand current knowledge of established pathways in VTE risk by combining clinical and genetic epidemiology. Apply affinity proteomics to identify novel plasma susceptibility biomarkers. Methods and results: 39 single nucleotide polymorphisms (SNPs) associated with coronary artery disease (CAD) and 18 risk VTE-SNPs from candidate gene approach studies or genome-wide association studies (GWAS) were identified from a literature search. The SNPs were genotyped in 2,835 women from the ThromboEmbolism Hormone study (TEHS), a Swedish nationwide case-control study in women (2002-2009). Association was assessed with logistic regression. Clinical and genetic predictors that contributed significantly to the fit of the logistic regression model were included in the prediction models. The genetic predictors that contributed to first VTE were assessed in a cohort of 1010 women with VTE from TEHS, followed up until a recurrence, death or November 2011 (TEHS follow-up). The SNP r579459 in the ABO locus was the only CAD-SNP that was significant associated with VTE (OR 1.57 (95% CI: 1.39-1.78, p= 6.4 10-13)). Seven VTE risk-SNPs (F5 rs6025, F2 rs1799963, ABO rs514659, FGG rs2066865, F11 rs2289252, PROC rs1799810 and KNG1 rs710446) with 4 SNP-SNP interactions contributed to the genetic risk score for VTE with an AUC of 0.66 (95% CI: 0.64-0.68). After adding clinical risk factors the AUC attained 0.84 (95% CI: 0.82-0.85). The goodness of fit of the genetic and combined scores improved when significant SNP-SNP interaction terms were included. In TEHS follow-up study, the overall recurrence rate was 20 per 1000 person-years (95% CI; 16-24). Carriers of the risk alleles of F5 rs6025 (FVL) (HR=1.7 (95% CI; 1.1-2.6)) and F11 rs2289252 (HR=1.8 (95% CI; 1.1-3.0)) had significantly higher rates of recurrence compared to non-carriers. The cumulative recurrence was 2.5-fold larger in carriers of both F5 rs6025 and F11 rs2289252 than in non-carriers at 5 years follow-up. Plasma samples from 88 VTE cases and 85 controls, part of the Venous thromboembolism Biomarker Study (VEBIOS), were screened against 408 candidate proteins targeted by 755 antibodies using multiplex bead arrays. Proteins that significantly associated with VTE after Bonferroni correction were tested for replication in plasma samples of 580 cases and 589 controls from the FARIVE study. In VEBIOS, plasma levels of four proteins, HIVEP1, VWF, GPX3 and PDGFB were significantly associated with VTE after Bonferroni correction. VWF and PDGFB successfully replicated in FARIVE with increased plasma levels in VTE cases compared to controls as initially observed in VEBIOS. Conclusion: ABO locus was the only shared genetic risk factor between CVD and VTE. A limited set of genetic predictors improved prediction of incident VTE in women at high risk. Our data indicated that interactions among SNPs increase the goodness of fit when predicting VTE. A combination of genotypes i.e. F11 rs2289252 and FVL, may be of potential clinical relevance for risk prediction for recurrence. Affinity plasma proteomics proved to be a valuable research strategy to discover novel biomarker

Markers of neutrophil activation and neutrophil extracellular traps in diagnosing patients with acute venous thromboembolism: A feasibility study based on two VTE cohorts

Background Venous thromboembolism (VTE) diagnosis would greatly benefit from the identification of novel biomarkers to complement D-dimer, a marker limited by low specificity. Neutrophil extracellular traps (NETs) have been shown to promote thrombosis and could hypothetically be used for diagnosis of acute VTE. Objectives To assess the levels of specific markers of neutrophil activation and NETs and compare their diagnostic accuracy to D-dimer. Methods We measured plasma levels of neutrophil activation marker neutrophil elastase (NE), the NET marker nucleosomal citrullinated histone H3 (H3Cit-DNA) and cell-free DNA in patients (n = 294) with suspected VTE (pulmonary embolism and deep vein thrombosis) as well as healthy controls (n = 30). A total of 112 VTE positive and 182 VTE negative patients from two prospective cohort studies were included. Results Higher levels of H3Cit-DNA and NE, but not cell-free DNA, were associated with VTE. Area under receiver operating curves (AUC) were 0.90 and 0.93 for D-dimer, 0.65 and 0.68 for NE and 0.60 and 0.67 for H3Cit-DNA in the respective cohorts. Adding NE and H3Cit-DNA to a D-dimer based risk model did not improve AUC. Conclusions Our study demonstrates the presence of neutrophil activation and NET formation in VTE using specific markers. However, the addition of NE or H3Cit-DNA to D-dimer did not improve the discrimination compared to D-dimer alone. This study provides information on the feasibility of using markers of NETs as diagnostic tools in acute VTE. Based on our findings, we believe the potential of these markers are limited in this setting

Effects of tumour necrosis factor on cardiovascular disease and cancer: A two-sample Mendelian randomization study.

BACKGROUND: Tumour necrosis factor (TNF) inhibitors are used in the treatment of certain autoimmune diseases but given the role of TNF in tumour biology and atherosclerosis, such therapies may influence the risk of cancer and cardiovascular disease. We conducted a Mendelian randomization study to explore whether TNF levels are causally related to cardiovascular disease and cancer. METHODS: Single-nucleotide polymorphisms associated with TNF levels at genome-wide significance were identified from a genome-wide association study of 30 912 European-ancestry individuals. Three TNF-associated single-nucleotide polymorphisms associated with higher risk of autoimmune diseases were used as instrumental variables. Summary-level data for 14 cardiovascular diseases, overall cancer and 14 site-specific cancers were obtained from UK Biobank and consortia. FINDINGS: Genetically-predicted TNF levels were positively associated with coronary artery disease (odds ratio (OR) 2.25; 95% confidence interval (CI) 1.50, 3.37) and ischaemic stroke (OR 2.27; 95% CI 1.50, 3.43), and inversely associated with overall cancer (OR 0.54; 95% CI 0.42, 0.69), breast cancer (OR 0.51; 95% CI 0.39, 0.67), and colorectal cancer (OR 0.20; 95% CI 0.09, 0.45). There were suggestive associations of TNF with venous thromboembolism (OR 2.18; 95% CI 1.32, 3.59), endometrial cancer (OR 0.25; 95% CI 0.07, 0.94), and lung cancer (OR 0.45; 95% CI 0.21, 0.94). INTERPRETATION: This study found evidence of causal associations of increased TNF levels with higher risk of common cardiovascular diseases and lower risk of overall and certain cancers

Joint health and treatment modalities in Nordic patients with moderate haemophilia A and B - The MoHem study

Introduction The prevalence of arthropathy in moderate haemophilia A (MHA) and B (MHB) is not well known. Aim We evaluated joint health in Nordic patients in relation to their treatment modality. Methods A cross-sectional, multicentre study covering MHA and MHB in Sweden, Finland and Norway. Arthropathy was evaluated by ultrasound (HEAD-US) and Haemophilia Joint Health Score (HJHS). Results We report on 145 patients: median age 28 years (IQR 13-52) and 61% MHA. Baseline factor VIII/factor IX activity (FVIII/FIX:C) was 2 IU/dL (median) (IQR 2-4): lower for MHB (2 IU/dL, IQR 1-2) than MHA (3 IU/dL, IQR 2-4) (P <.01). Eighty-five per cent of MHA and 73% MHB had a history of haemarthrosis (P = .07). Age at first joint bleed was lower for MHA (5 years [median], IQR 3-7) than MHB (7 years, IQR 5-12) (P = .01). Thirty-eight per cent received prophylaxis, started at median 10 years of age (IQR 4-24). Median joint bleeds and serious other bleeds during the last 12 months were both zero (IQR 0-1). Total HEAD-US captured 0/48 points (median) (IQR 0-2) and HJHS 4/120 points (IQR 1-10) with strong correlation between them (r = .72). FVIII/FIX:CPeer reviewe

Direct Reprogramming of Human Fetal- and Stem Cell-Derived Glial Progenitor Cells into Midbrain Dopaminergic Neurons

Human glial progenitor cells (hGPCs) are promising cellular substrates to explore for the in situ production of new neurons for brain repair. Proof of concept for direct neuronal reprogramming of glial progenitors has been obtained in mouse models in vivo, but conversion using human cells has not yet been demonstrated. Such studies have been difficult to perform since hGPCs are born late during human fetal development, with limited accessibility for in vitro culture. In this study, we show proof of concept of hGPC conversion using fetal cells and also establish a renewable and reproducible stem cell-based hGPC system for direct neural conversion in vitro. Using this system, we have identified optimal combinations of fate determinants for the efficient dopaminergic (DA) conversion of hGPCs, thereby yielding a therapeutically relevant cell type that selectively degenerates in Parkinson's disease. The induced DA neurons show a progressive, subtype-specific phenotypic maturation and acquire functional electrophysiological properties indicative of DA phenotype

Treatment outcomes in persons with severe haemophilia B in the Nordic region : The B-NORD study

Introduction Data on outcome in persons with haemophilia B (PwHB) are limited and mainly extrapolated from studies of haemophilia A (HA). Aim To characterize treatment outcomes in persons with severe HB in the Nordic region, with a focus on joint health, compared with matched controls with HA. Methods PwHB attending haemophilia centres in Denmark, Finland, Norway and Sweden were enrolled and matched with controls with HA. Joint assessment using Haemophilia Joint Health Score (HJHS) and ultrasound according to Haemophilia Early Arthropathy Detection protocol (HEAD-US) was conducted. Adherence was evaluated using the Validated Haemophilia Regimen Treatment Adherence Scale (VERITAS). Results Seventy-nine males with HB, with median age of 30 years (range 1-75), were enrolled. Eleven patients (14%) had a history of or current inhibitor. Twenty-nine PwHB (37%) reported joint bleeds during the prior year, and 35% had previously undergone joint surgery. Ninety-five per cent were on prophylaxis, and 70% used recombinant concentrates, with a median factor consumption of 3,900 IU/kg/year for standard half-life products. Only two patients had a VERITAS score corresponding to 'non-adherence'. Joint health, assessed with HJHS, showed a significant lower score among PwHB compared with HA controls, explained by a difference in the 18-49 age group, without observed differences in older or younger subgroups. The HEAD-US scores were overall low. Conclusion The Nordic cohort of PwHB is well treated by prophylaxis, but the goal of zero bleeds for all is not reached. Our findings suggest that patients with severe HB suffer from a milder arthropathy than patients with severe HA.Peer reviewe

Plasma Phospholipid Fatty Acids, FADS1 and Risk of 15 Cardiovascular Diseases: A Mendelian Randomisation Study

Whether circulating fatty acids (FAs) play a causal role in the development of cardiovascular disease (CVD) remains unclear. We conducted a Mendelian randomisation study to explore the associations between plasma phospholipid FA levels and 15 CVDs. Summary-level data from the CARDIoGRAMplusC4D, MEGASTROKE, and Atrial Fibrillation consortia and UK Biobank were used. Sixteen single-nucleotide polymorphisms (SNPs) associated with ten plasma FAs were used as instrumental variables. SNPs in or close to the FADS1 gene were associated with most FAs. We performed a secondary analysis of the association between a functional variant (rs174547) in FADS1, which encodes ?5-desaturase (a key enzyme in the endogenous FA synthesis), and CVD. Genetic predisposition to higher plasma α-linolenic, linoleic, and oleic acid levels was associated with lower odds of large-artery stroke and venous thromboembolism, whereas higher arachidonic and stearic acid levels were associated with higher odds of these two CVDs. The associations were driven by SNPs in or close to FADS1. In the secondary analysis, the minor allele of rs174547 in FADS1 was associated with significantly lower odds of any ischemic stroke, large-artery stroke, and venous thromboembolism and showed suggestive evidence of inverse association with coronary artery disease, abdominal aortic aneurysm and aortic valve stenosis. Genetically higher plasma α-linolenic, linoleic, and oleic acid levels are inversely associated with large-artery stroke and venous thromboembolism, whereas arachidonic and stearic acid levels are positively associated with these CVDs. The associations were driven by FADS1, which was also associated with other CVDs.Funding for this study came from the Swedish Research Council for Health, Working Life and Welfare (Forte; Grant Number 2018-00123) and the Swedish Research Council (Vetenskapsrådet; Grant Number 2019-00977). SB is supported by a Sir Henry Dale Fellowship jointly funded by the Wellcome Trust and the Royal Society (Grant Number 204623/Z/16/Z)

Factor IX antibodies and tolerance in hemophilia B in the Nordic countries - The impact of F9 variants and complications

Introduction: The development of inhibitory antibodies (inhibitors) in persons with hemophilia B (PwHB) causes significant morbidity. Data on the impact of the F9 variant and immune tolerance induction (ITI) outcome are limited.The aim of this study was to investigate the presence of neutralizing and non-neutralizing antibodies (NNA) in severe hemophilia B (HB) and to evaluate ITI outcome and complications in relation to the pathogenic F9 variant.Materials and methods: Persons with severe HB in the Nordic countries were enrolled and information on F9 variants, inhibitors, ITI and complications were collected. Analyses of anti-FIX antibodies with a fluorescence -immunoassay (xFLI) and an ELISA method were conducted.Results: Seventy-nine PwHB were enrolled. Null variants were seen in 33 (42 %) PwHB and 12 (15 %) had a current or former inhibitor. Eleven (92 %) of the inhibitor patients had experienced allergic manifestations and three (25 %) nephrotic syndrome. Of 10 PwHB with at least one ITI attempt, eight (80 %) were considered tolerant at enrolment. Immunosuppression was included in seven of eight successful or partially successful at-tempts. Five PwHB had at least one ITI failure before a successful or partially successful ITI. No NNA could be identified.Conclusion: A high proportion of severe F9 gene defects among persons with severe HB in the Nordic countries may explain the observed relatively high prevalence of inhibitors. ITI success was independent of the F9 variant and attained despite allergic manifestations and previous ITI failures. Inclusion of immunosuppression tenta-tively enhances the chances of ITI success. No NNA were observed.Peer reviewe

Are patents with multiple inventors from different countries a good indicator of international R&amp;D collaboration? The case of ABB

Based on the critical case of ABB, this paper questions the relevance of using patents with multiple inventors from different countries (“cross-country patents”) as an indicator of international R&amp;D collaboration. The study shows that less than half of ABB’s cross-country patents are the result of international R&amp;D collaboration as described by one of the more inclusive definitions found in previous literature. Only a third of the patents are the result of joint R&amp;D activities between different MNC subsidiaries or firms. We also discuss the implications of our study for the assignment of patents to countries based on inventor addresses

Causal effect of renal function on venous thromboembolism : a two-sample Mendelian randomization investigation

Whether renal function is causally associated with venous thromboembolism (VTE) is not yet fully elucidated. We conducted a two-sample Mendelian randomization (MR) study to determine the causal effect of renal function, measured as estimated glomerular filtration rate (eGFR), on VTE. Single-nucleotide polymorphisms associated with eGFR were selected as instrumental variables at the genome-wide significance level (p &lt; 5 × 10-8) from a meta-analysis of 122 genome-wide association studies including up to 1,046,070 individuals. Summary-level data for VTE were obtained from the FinnGen consortium (6913 VTE cases and 169,986 non-cases) and UK Biobank study (4620 VTE cases and 356,574 non-cases). MR estimates were calculated using the random-effects inverse-variance weighted method and combined using fixed-effects meta-analysis. Genetically predicted decreased eGFR was significantly associated with an increased risk of VTE in both FinnGen and UK Biobank. For one-unit decrease in log-transformed eGFR, the odds ratios of VTE were 2.93 (95% confidence interval (CI) 1.25, 6.84) and 4.46 (95% CI 1.59, 12.5) when using data from FinnGen and UK Biobank, respectively. The combined odds ratio was 3.47 (95% CI 1.80, 6.68). Results were consistent in all sensitivity analyses and no horizontal pleiotropy was detected. This MR-study supported a casual role of impaired renal function in VTE