Associations of tissue factor and tissue factor pathway inhibitor with organ dysfunctions in septic shock

Coagulopathy, microvascular alterations and concomitant organ dysfunctions are hallmarks of sepsis. Attempts to attenuate coagulation activation with an inhibitor of tissue factor (TF), i.e. tissue factor pathway inhibitor (TFPI), revealed no survival benefit in a heterogenous group of sepsis patients, but a potential survival benefit in patients with an international normalized ratio (INR) < 1.2. Since an increased TF/TFPI ratio determines the procoagulant activity specifically on microvascular endothelial cells in vitro, we investigated whether TF/TFPI ratio in blood is associated with INR alterations, organ dysfunctions, disseminated intravascular coagulation (DIC) and outcome in septic shock. Twenty-nine healthy controls (HC) and 89 patients with septic shock admitted to a tertiary ICU were analyzed. TF and TFPI in blood was analyzed and related to organ dysfunctions, DIC and mortality. Patients with septic shock had 1.6-fold higher levels of TF and 2.9-fold higher levels of TFPI than HC. TF/TFPI ratio was lower in septic shock compared to HC (0.003 (0.002-0.005) vs. 0.006 (0.005-0.008), p < 0.001). Non-survivors had higher TFPI levels compared to survivors (43038 (29354-54023) vs. 28041 (21675-46582) pg/ml, p = 0.011). High TFPI levels were associated with acute kidney injury, liver dysfunction, DIC and disease severity. There was a positive association between TF/TFPI ratio and troponin T (b = 0.531 (0.309-0.754), p < 0.001). A high TF/TFPI ratio is exclusively associated with myocardial injury but not with other organ dysfunctions. Systemic TFPI levels seem to reflect disease severity. These findings point towards a pathophysiologic role of TF/TFPI in sepsis-induced myocardial injury.

Plasma tissue factor pathway inhibitor levels in coronavirus disease 2019 patients: a systematic review and meta-analysis

Studies have suggested a relationship between tissue factor pathway inhibitor (TFPI) and coronavirus disease 2019 (COVID-19) severity. However, there is inconsistency in the findings of the studies. To enhance comprehension of this relationship, a meta-analysis was conducted. PubMed, Web of Science, and Scopus databases were searched to identify eligible studies. The mean difference was employed as effect measures and the standardized mean difference (SMD) and the 95% confidence interval (CI) were utilized as a summary statistic. Heterogeneity was assessed through the application of the chi-square test and the I2 statistic. The included studies' quality and risk of bias were assessed using the Newcastle-Ottawa assessment scale, adapted for case-control studies. A total of six studies were included with 684 cases and healthy controls (180 healthy controls and 504 COVID-19 patients with different severity, 76 mild, 292 moderate, and 136 severe). The analysis revealed a significant increase in the TFPI level in COVID-19 patients with moderate severity compared with healthy controls (SMD = 0.95 ng/ml, 95% confidence interval (CI) 0.27, 1.63 ng/ml; I2 : 87.2%). The increased TFPI level in mild and moderate COVID-19 was not significant, SMD = 0.68 ng/ml, 95% CI -0.64 to 2.0 ng/ml; I2 92.9% and SMD = 0.62 ng/ml, 95% CI -0.62 to 1.86 ng/ml; I2 91.5%, respectively. In addition, most studies indicate an association of the increased TFPI concentrations with increased markers of inflammation, endothelial damage, and hypercoagulation. Considering the anticoagulant and anti-inflammatory roles of TFPI, its increase seems to be aimed at modulating COVID-19-induced hyper-inflammation and hyper-coagulation state.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42023437353.

Pathophysiology of the Antiphospholipid Antibody Syndrome

The antiphospholipid syndrome is characterized by antibodies directed against phospholipid-binding proteins and phospholipids attached to cell membrane receptors, mitochondria, oxidized lipoproteins, and activated complement components. When antibodies bind to these complex antigens, cells are activated and the coagulation and complement cascades are triggered, culminating in thrombotic events and pregnancy morbidity that further define the syndrome. The phospholipid-binding proteins most often involved are annexins II and V, β2-glycoprotein I, prothrombin, and cardiolipin. A distinguishing feature of the antiphospholipid syndrome is the "lupus anticoagulant". This is not a single entity but rather a family of antibodies directed against complex antigens consisting of β2-glycoprotein I and/or prothrombin bound to an anionic phospholipid. Although these antibodies prolong in vitro clotting times by competing with clotting factors for phospholipid binding sites, they are not associated with clinical bleeding. Rather, they are thrombogenic because they augment thrombin production in vivo by concentrating prothrombin on phospholipid surfaces. Other antiphospholipid antibodies decrease the clot-inhibitory properties of the endothelium and enhance platelet adherence and aggregation. Some are atherogenic because they increase lipid peroxidation by reducing paraoxonase activity, and others impair fetal nutrition by diminishing placental antithrombotic and fibrinolytic activity. This plethora of destructive autoantibodies is currently managed with immunomodulatory agents, but new approaches to treatment might include vaccines against specific autoantigens, blocking the antibodies generated by exposure to cytoplasmic DNA, and selective targeting of aberrant B-cells to reduce or eliminate autoantibody production.

Relationship between osteonecrosis and antiphospholipid antibodies in patients with systemic lupus erythematosus: a systematic review protocol

INTRODUCTION

Osteonecrosis (ON) is characterised by the destruction of the normal blood supply to the bone tissue. ON is the main cause of disability in patients with systemic lupus erythematosus (SLE). Studies have reported the existence of many risk factors for SLE complicated by ON, including the use of high-dose glucocorticoids and high disease activity. The correlation between antiphospholipid antibodies (aPLs) and ON in SLE has been controversial. We aim to conduct a systematic review of the literature related to SLE, aseptic ON and aPLs, to provide a reference for the clinical screening of high-risk patients and for early prevention.

METHODS AND ANALYSIS

The following six databases will be searched: MEDLINE/PubMed, Embase, Web of Science, Chinese Biomedical Literature Database, Wan-Fang Database and China National Knowledge Infrastructure. The database searches will not be restricted by date. Case-control studies, cohort studies or observational studies that compare aPLs between SLE patients with and without ON will be considered eligible. Articles published in English and Chinese will be included. Two researchers will independently perform the processes of study selection, data extraction and study quality assessment. The Newcastle-Ottawa Quality Assessment Scale will be used to assess the quality of the retrieved studies. A meta-analysis will be performed after screening the studies. Data will be analysed using ORs for dichotomous data.

ETHICS AND DISSEMINATION

Ethical approval is not required because this systematic review will use published data. The systematic review will be electronically disseminated through a peer-reviewed publication or conference presentations.

PROSPERO REGISTRATION NUMBER

CRD42020209637.

Frequency of Systemic Lupus Erythematosus Was Decreasing Among Hospitalized Patients From 2013 to 2017 in a National Database in China

Backgrounds: Limited data was reported for the frequency of SLE in China. The aim of this study was to investigate the frequency, geographical, and ethnic distributions of hospitalized SLE patients with data from the Hospital Quality Monitoring System (HQMS) in China.

Methods: Hospitalized patients were investigated from a national inpatient database covering 46.0% of tertiary hospitals in China from 2013 to 2017. Data regarding the diagnosis of SLE were extracted based on ICD-10 codes. We collected and analyzed data from the front page of the records of inpatients, including frequency, demographic characteristics, and geographic distributions of SLE.

Results: Among 158.3 million inpatients attended during the study period, 0.31% (491, 225) were diagnosed with SLE. The frequency of SLE decreased during the study period (from 0.30% in 2013 to 0.27% in 2017). The frequency of SLE increased with latitude (0.21% in northern China and 0.39% in southern China in 2017). Hospitalizations mostly occurred in winter (31.24%). The Li population had the highest frequency of patients with SLE (0.76%). The all-cause in-hospital mortality rate of SLE decreased from 0.74% (255/34,746) in 2013 to 0.54% (295/54,168) in 2017. The percentage of SLE patients with infections increased from 3.14% in 2013 to 4.72% in 2017. The percentage of SLE patients with tumors and thrombosis also increased slightly from 0.85 and 1.43% in 2013 to 1.27 and 2.45% in 2017, respectively.

Conclusion: This study provided epidemiological information of SLE in hospitalized patients in China for the first time. An ethnic and spatial clustering trend of SLE was observed.

Comprehensive aptamer-based screening identifies a spectrum of urinary biomarkers of lupus nephritis across ethnicities

Emerging urinary biomarkers continue to show promise in evaluating lupus nephritis (LN). Here, we screen urine from active LN patients for 1129 proteins using an aptamer-based platform, followed by ELISA validation in two independent cohorts comprised of 127 inactive lupus, 107 active LN, 67 active non-renal lupus patients and 74 healthy controls, of three different ethnicities. Urine proteins that best distinguish active LN from inactive disease are ALCAM, PF-4, properdin, and VCAM-1 among African-Americans, sE-selectin, VCAM-1, BFL-1 and Hemopexin among Caucasians, and ALCAM, VCAM-1, TFPI and PF-4 among Asians. Most of these correlate significantly with disease activity indices in the respective ethnic groups, and surpass conventional metrics in identifying active LN, with better sensitivity, and negative/positive predictive values. Several elevated urinary molecules are also expressed within the kidneys in LN, based on single-cell RNAseq analysis. Longitudinal studies are warranted to assess the utility of these biomarkers in tracking lupus nephritis.

Urinary pro-thrombotic, anti-thrombotic, and fibrinolytic molecules as biomarkers of lupus nephritis

Objective

This study evaluates the utility of urinary pro-thrombotic molecules such as tissue factor (TF), anti-thrombotic molecules such as tissue factor pathway inhibitor (TFPI), and fibrinolytic molecules such as plasmin and d-dimer as biomarkers of lupus nephritis (LN).

Methods

Urine samples from 113 biopsy-proven LN patients (89 active LN and 24 inactive LN), 45 chronic kidney disease patients, and 41 healthy controls were examined for d-dimer, plasmin, TF, and TFPI levels by ELISA. The area under the receiver operating characteristic curve (AUC) analysis, multivariate regression analysis, and Bayesian network analysis were performed to assess the diagnostic value of the assayed molecules in LN.

Results

Although urinary d-dimer, plasmin, TF, and TFPI were all elevated in active LN compared to all control groups, and correlated with rSLEDAI and SLICC RAS disease activity indices, urine plasmin emerged as the strongest independent predictor of eGFR and renal disease status, by multivariate regression analysis and Bayesian network analysis. Whereas urine plasmin discriminated active LN from inactive disease with an AUC of 0.84, the combination of urine plasmin and TFPI discriminated ALN from ILN with an AUC of 0.86, with both surpassing the specificity and positive predictive value of traditional markers such as anti-dsDNA and complement C3.

Conclusion

Both thrombogenic and thrombolytic cascades appear to be upregulated in lupus nephritis, with proteins from both cascades appearing in the urine. Of the coagulation cascade proteins surveyed, urine plasmin emerges as the strongest predictor of eGFR and clinical renal disease in patients with LN.

Electronic supplementary material

The online version of this article (10.1186/s13075-019-1959-y) contains supplementary material, which is available to authorized users.

Haemorheological and haemostatic alterations in coeliac disease and inflammatory bowel disease in comparison with non-coeliac, non-IBD subjects (HERMES): a case-control study protocol

INTRODUCTION

Haemorheological and haemostatic changes predispose to the development of arterial and venous thrombotic events; however, limited information is available on the status of these changes in coeliac disease (CeD) and inflammatory bowel disease (IBD). In this study, we aim to describe the haemorheological and haemostatic profiles of CeD and IBD patients in a Hungarian cohort of patients to investigate whether any alterations contribute to elevated thrombotic risk.

METHODS AND ANALYSIS

This is a case-control study involving newly diagnosed and followed CeD and IBD patients with age-matched and sex-matched non-CeD, non-IBD subjects with an allocation ratio of 1:1:1.After informed consent is obtained, a detailed medical history will be collected, including venous and arterial thrombotic risk factors and medications. Symptoms in CeD patients will be assessed with the Gastrointestinal Symptoms Rating Scale, and disease activity in IBD patients will be determined by disease-specific scores. Dietary adherence will be assessed among CeD patients with a thorough interview together with a measurement of self-reported adherence, dietary knowledge and urine analysis (detection of gluten immunogenic peptides). In addition to routine laboratory parameters, haemorheological (ie, erythrocyte deformability and aggregation, viscosity of whole blood and plasma) and haemostatic parameters (eg, protein C, protein S and antithrombin) with immunological indicators (ie, coeliac-specific serology and antiphospholipid antibodies) will be measured from venous blood for every participant.Primary and secondary outcomes will be haemorheological and haemostatic parameters, respectively. Univariate and multivariate statistics will be used to compare CeD and IBD patients to control subjects. Subgroup analysis will be performed by disease type in IBD, (Crohn's disease and ulcerose colitis), dietary adherence in CeD, and disease activity in IBD and CeD.

ETHICS AND DISSEMINATION

The study was approved by the Regional and Local Research Ethics Committee, University of Pécs (Ref. No. 6917). Findings will be disseminated at research conferences and in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ISRCTN49677481.

Changes to fibrinolysis in patients with systemic lupus erythematosus are associated with endothelial cell damage and inflammation, but not antiphospholipid antibodies

We investigated whether changes to fibrinolysis were associated with other manifestations of systemic lupus erythematosus (SLE), including antiphospholipid (APL) antibody status, endothelial damage, and inflammation. Ninety-four patients (36 SLE patients, 58 healthy controls) were recruited from Tasmania, Australia. Circulating levels of plasminogen, α2-antiplasmin, tissue-type plasminogen activator, plasminogen activator inhibitor-1, and thrombin-activatable fibrinolysis inhibitor (TAFI) were measured, as well as APL antibodies (including lupus anticoagulant, anticardiolipin, and antibeta-2 glycoprotein-1 antibodies), soluble E-selectin, and interleukin-6. Whereas there was a significant decrease in plasminogen (patient vs. control; median) (210 vs. 444 ng/ml; P < 0.0001) and increase in α2-antiplasmin (0.53 vs. 0.09 μg/ml; P = 0.0007), there was increased t-PA (0.65 vs. 0.40 ng/ml; P = 0.0001) and decreased TAFI (8.8 vs. 10.0 ng/ml; P = 0.002) in SLE patients compared to healthy controls. Plasminogen was significantly associated with α2-antiplasmin (rho = -0.563, P < 0.001); TAFI (rho = 0.410, P = 0.011); soluble E-selectin (rho = 0.531, P = 0.001); and interleukin-6 (rho = 0.489, P = 0.002) in SLE patients; however, APL antibody status was not associated with any of the markers measured. This study has demonstrated that fibrinolysis is significantly altered in patients with SLE compared to controls, and associated with endothelial cell damage and inflammation, but not APL antibody status.

Microparticles in the blood of patients with systemic lupus erythematosus (SLE): phenotypic characterization and clinical associations

Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease characterized by circulating autoantibodies and the formation of immune complexes. In these responses, the selecting self-antigens likely derive from the remains of dead and dying cells, as well as from disturbances in clearance. During cell death/activation, microparticles (MPs) can be released to the circulation. Previous MP studies in SLE have been limited in size and differ regarding numbers and phenotypes. Therefore, to characterize MPs more completely, we investigated 280 SLE patients and 280 individually matched controls. MPs were measured with flow cytometry and phenotyped according to phosphatidylserine expression (PS⁺/PS⁻), cellular origin and inflammatory markers. MPs, regardless of phenotype, are 2–10 times more abundant in SLE blood compared to controls. PS⁻ MPs predominated in SLE, but not in controls (66% vs. 42%). Selectively in SLE, PS⁻ MPs were more numerous in females and smokers. MP numbers decreased with declining renal function, but no clear association with disease activity was observed. The striking abundance of MPs, especially PS⁻ MPs, suggests a generalized disturbance in SLE. MPs may be regarded as “liquid biopsies” to assess the production and clearance of dead, dying and activated cells, i.e. pivotal events for SLE pathogenesis.

Evasion and interactions of the humoral innate immune response in pathogen invasion, autoimmune disease, and cancer

The humoral innate immune system is composed of three major branches, complement, coagulation, and natural antibodies. To persist in the host, pathogens, such as bacteria, viruses, and cancers must evade parts of the innate humoral immune system. Disruptions in the humoral innate immune system also play a role in the development of autoimmune diseases. This review will examine how Gram positive bacteria, viruses, cancer, and the autoimmune conditions systemic lupus erythematosus and anti-phospholipid syndrome, interact with these immune system components. Through examining evasion techniques it becomes clear that an interplay between these three systems exists. By exploring the interplay and the evasion/disruption of the humoral innate immune system, we can develop a better understanding of pathogenic infections, cancer, and autoimmune disease development.

Tissue factor pathway inhibitor and thrombin-activatable carboxypeptidase B for prediction of early atherosclerosis in gouty arthritis

BACKGROUND

Gouty arthritis (GA) is a chronic inflammatory arthritis in which both clinical and subclinical atherosclerosis are more frequent. The dynamic equilibrium between coagulation and fibrinolysis is impaired in inflammatory diseases. We determined TFPI and TAFI antigen levels in GA patients and evaluated their association with subclinical atherosclerosis.

METHODS

We included 45 GA patients (41 males, 4 females; mean age: 51.6years) and 25 asymptomatic hyperuricemic (AHU) subjects (19 males, 6 females; mean age: 48.1years). Cardiovascular risk factors were determined. TAFI and TFPI levels were determined by ELISA. B-mode ultrasonography was used to detect subclinical atherosclerosis.

RESULTS

Cardiovascular risk factors were similar in both groups. The carotid IMT was significantly higher in GA group than in AHU group (0.74±0.23mm vs. 0.61±0.13mm, p=0.009). TFPI level was significantly higher in GA group than in AHU group (86.2±48.9ng/mL vs. 25.8±21.4ng/mL, p<0.001); TAFI antigen was significantly higher in AHU group (22.6±3.6ng/mL vs. 25.7±5.3ng/mL, p=0.006) than in GA patients. Atherosclerotic plaque formation was more frequent in GA group (p=0.041). When GA patients with and without plaques were compared, the first group had significantly higher mean age (p=0.01) and TFPI level (p=0.028). TFPI level correlated with carotid IMT (r=0.302; p=0.028). Logistic regression analysis showed that age (OR: 1.236, 95%CI: 1.059-1.443, p=0.007) and TFPI (OR: 1.031, 95%CI: 1.008-1.054, p=0.008) were independent risk factors for the presence of plaques.

CONCLUSIONS

GA patients had more frequent subclinical atherosclerosis than subjects with AHU. Higher TFPI levels in GA patients -probably associated with enhanced endothelial damage- were related to subclinical atherosclerosis. Lower TAFI levels in GA pointed to impaired fibrinolysis.

Anti-human protein S antibody induces tissue factor expression through a direct interaction with platelet phosphofructokinase

INTRODUCTION

Autoantibodies including anti-human protein S antibody (anti-hPS Ab) and anti-human protein C antibody (anti-hPC Ab) can be detected in patients with autoimmune diseases with hypercoagulability. The objective of the present study was to determine the effects and molecular pathways of these autoantibodies on tissue factor (TF) expression in human coronary artery endothelial cells (HCAECs).

MATERIALS AND METHODS

HCAECs were treated with anti-hPS Ab or anti-hPC Ab for 3 hours. TF expression was measured by real-time PCR and Western blot. TF-mediated procoagulant activity was determined by a commercial kit. MAPK phosphorylation was analyzed by Bio-Plex luminex immunoassay and Western blot. The potential proteins interacting with anti-hPS Ab were studied by immunoprecipitation, mass spectrometry and in vitro pull-down assay.

RESULTS

Anti-hPS Ab, but not anti-hPC Ab, specifically induced TF expression and TF-mediated procoagulant activity in HCAECs in a concentration-dependent manner. This effect was confirmed in human umbilical endothelial cells (HUVECs). ERK1/2 phosphorylation was induced by anti-hPS Ab treatment, while inhibition of ERK1/2 by U0216 partially blocked anti-hPS Ab-induced TF upregulation (P<0.05). In addition, anti-hPS Ab specifically cross-interacted with platelet phosphofructokinase (PFKP) in HCAECs. Anti-hPS Ab was able to directly inhibit PFKP activities in HCAECs. Furthermore, silencing of PFKP by PFKP shRNA resulted in TF upregulation in HCAECs, while activation of PFKP by fructose-6-phosphate partially blocked the effect of anti-hPS Ab on TF upregulation (P<0.05).

CONCLUSIONS

Anti-hPS Ab induces TF expression through a direct interaction with PFKP and ERK1/2 activation in HCAECs. Anti-hPS Ab may directly contribute to vascular thrombosis in the patient with autoimmune disorders.

Anti-prothrombin (aPT) and anti-phosphatidylserine/prothrombin (aPS/PT) antibodies and the risk of thrombosis in the antiphospholipid syndrome. A systematic review

Antibodies to prothrombin are detected by directly coating prothrombin on irradiated ELISA plates (aPT) or by using the phosphatidylserine/prothrombin complex as antigen (aPS/PT). Although these antibodies have both been associated with antiphospholipid syndrome (APS) and a correlation between the two assays have been reported, it seems that aPT and aPS/PT belong to different populations of autoantibodies. It was our objective to systematically review the available evidence on aPT and aPS/PT antibodies and the risk of thrombosis in APS. Medline-reports published between 1988 and 2013 investigating aPT and aPS/PT as a risk factor for thrombosis were included. Whenever possible, antibody isotype(s) and site of thrombosis were analysed. This systematic review is based on available data from more than 7,000 patients and controls from 38 studies analysing aPT and 10 aPS/PT. Antibodies to prothrombin (both aPT and aPS/PT) increased the risk of thrombosis (odds ratio [OR] 2.3; 95% confidence interval [CI] 1.72-3.5). aPS/PT seemed to represent a stronger risk factor for thrombosis, both arterial and/or venous than aPT (OR 5.11; 95%CI 4.2-6.3 and OR 1.82; 95%CI 1.44-2.75, respectively). In conclusion, routine measurement of aPS/PT (but not aPT) might be useful in establishing the thrombotic risk of patients with previous thrombosis and/or systemic lupus erythematosus. Their inclusion as laboratory criteria for the APS should be indisputably further explored.

Anti-β2GP1 antibodies have variable effects on platelet aggregation

AIM

To investigate the effects of affinity-purified rabbit anti-β2GP1, and anti-β2GP1 purified from patients with systemic lupus erythematosus (SLE), on adenosine diphosphate (ADP)-induced aggregation.

METHODS

Whole blood was collected and processed to obtain platelet poor plasma (PPP) from normal controls (n = 15) and SLE patients (n = 15). Using PPP, anti-β2GP1 titres were determined using an ELISA and IgG fractions isolated using a HiTrap protein G column. Anti-β2GP1 was purified from two SLE patients using purified β2GP1 coupled to a HiTrap NHS-activated HP column.

RESULTS

The effect of rabbit and human derived anti-β2GP1 (0-100 μg/mL), on ADP (2.5, 5 μM) induced platelet aggregation were investigated using light transmission aggregometry. Rabbit anti-β2GP1 significantly inhibited all parameters of 5 μM ADP-induced platelet aggregation; %Max (p = 0.028), %AUC (p = 0.014) and slope (p < 0.001). In contrast, anti-β2GP1 purified from SLE patients significantly enhanced the %Max (p = 0.031) and %AUC (p = 0.007) in a concentration dependent manner, but inhibited the slope (p < 0.05) of 5 μM ADP-induced platelet aggregation.

CONCLUSION

Our data suggest anti-β2GP1 purified from different species have variable effects on in vitro platelet aggregation. The disparity between rabbit and human anti-β2GP1 may be due to the heterogeneous nature of anti-β2GP1, varying avidity or different antibody binding specificities between species.