Anticoagulant and signaling functions of antithrombin

Comparison of anticoagulant vacutainer blood collection tubes on rainbow trout (Oncorhynchus mykiss) leukocyte viability during long-term storage

Peripheral blood leukocytes (PBL) are critical for understanding systemic immune responses and assessing the organism's health. In immunological studies, particularly with aquaculture-relevant species like Rainbow trout (Oncorhynchus mykiss), ensuring PBL viability during sample storage is important, especially when samples must be transported over long distances. Anticoagulants are essential for preventing blood clotting and preserving cellular integrity; however, their effects on leukocyte populations in salmonids remain poorly studied. This study aimed to evaluate the impact of four anticoagulants-ethylenediaminetetraacetic acid (EDTA), sodium citrate, sodium heparin, and lithium heparin-on the viability of PBL populations in rainbow trout, with a comparative analysis of human PBL. Blood samples were stored for up to seven days, and cell viability and leukocyte population percentages were assessed by flow cytometry at 0, 1-, 2-, 4-, and 7-days post-collection (dpc). Results showed that sodium heparin and lithium heparin were the most effective anticoagulants for preserving trout leukocyte viability, maintaining percentages greater than 70 % up to 4 dpc. In contrast, EDTA and sodium citrate were less effective in maintaining cell viability. In human PBL samples, EDTA was the most effective anticoagulant, with lymphocyte viability exceeding 80 % at 7 dpc. Sodium heparin and lithium heparin also preserved human PBL viability comparably up to 4 dpc, but their efficacy decreased significantly by 7 dpc. These findings highlight the species-specific effects of anticoagulants, recommending heparin-based anticoagulants for long-term leukocyte preservation in rainbow trout (up to 4 dpc). In addition, this study provides valuable information for blood handling protocols in immunological research.

Real-time imaging of blood coagulation and angiogenesis during development in a zebrafish model of type I antithrombin deficiency

Severe type I antithrombin (AT) deficiency is considered to cause embryonic lethality. Although several pathological analyses using mice or zebrafish have been attempted, the previous studies did not unveil the detailed mechanism leading to lethality in the early developmental stage. In order to solve this problem, we established type I AT deficient zebrafish by the CRISPR/Cas9 system into Tg(gata1:dsRed) and Tg(fli1a:GFP) lines, so that we could conduct real-time imaging of thrombosis and angiogenesis using fluorescence stereo zoom microscopy. The established zebrafish AT (zAT) mutants harbored frameshift mutations which resulted to be type I AT deficient, unable to secrete zAT protein into blood. Both heterozygous (zAT+/-) and homozygous (zAT-/-) mutants showed reduced survival rate and diverse thrombosis up to 9 days post fertilization. In addition, blood vessel formation was delayed at 30 hpf in zAT-/-, which was recovered normally by 5 dpf and had little effect on survival. Notably, we analyzed the differences in gene expression profiles under AT-depleted conditions by real-time quantitative PCR, and zAT-/- juvenile zebrafish showed increased PLG gene expression and decreased F2 gene expression. Our in vivo study revealed the effects of AT deficiency on embryos during development from the aspects of coagulation and vascular formation.

Genome-wide association study-driven identification of thrombomodulin and factor V as the best biomarker combination for deep vein thrombosis

Deep vein thrombosis (DVT) is a clinically significant condition characterized by the formation of thrombi in deep venous structures, leading to high morbidity and potential mortality. Identifying reliable biomarkers for DVT risk prediction remains challenging due to the intricate genetic and molecular mechanisms underlying the disease. This study aims to investigate the best biomarker for DVT. Our study utilized genome-wide association studies (GWAS) findings coupled with a functional annotation scoring system to identify and prioritize genetic markers with strong associations to DVT. Furthermore, gene expression levels were analyzed to determine the most promising genetic markers. Several databases were utilized, including the GWAS Catalog, HaploReg 4.2, WebGestalt, Enrichr, and the GTEx Portal. Through the comprehensive analysis, we found 5 potential biomarkers and highlighted thrombomodulin (THBD) and Factor V (F5) as the best blood-based biomarkers. THBD and F5 genes were selected based on their elevated expression levels in blood and the presence of eQTLs. Functionally, THBD modulates coagulation via protein C activation, while F5 is pivotal in thrombin formation and clot stabilization, underscoring their mechanistic relevance to DVT pathogenesis, and rendering them suitable for non-invasive clinical assessment. Our findings emphasize the potential of genetic biomarkers to transform DVT risk assessment and support advancements in precision medicine for thrombotic disorders.

Efficacy and safety of antithrombin or recombinant human thrombomodulin in the treatment of disseminated intravascular coagulation: A systematic review and meta-analysis

OBJECTIVE

Multiple organ damage is a hallmark of the highly lethal condition known as disseminated intravascular coagulation (DIC). The efficacy and safety of recombinant human soluble thrombomodulin (rhTM) and antithrombin (AT) in DIC is still debatable. Therefore, we used a fixed-effects model to conduct a comprehensive evaluation and meta-analysis to examine the safety and efficacy of AT or rhTM administration for treating DIC.

METHODS

Up until September 2024, the databases of the Cochrane Library, Embase, Web of Science, PubMed, and CNKI were searched for pertinent papers that satisfied the inclusion requirements. Following the researchers' review of the literature, data extraction, and quality assessment, RevMan 5.4 software was used to conduct meta-analysis.

RESULTS

The AT group included two randomized controlled trials with 95 patients, 47 in the test and 48 in the control groups. The test group's DIC resolution rate was higher than the control group's (OR = 5.21 [2.10, 12.90], P = 0.0004), while the 28-day mortality and bleeding-related adverse events did not differ significantly (OR = 0.45 [0.16, 1.31], P = 0.14; OR = 1.02 [0.22, 4.74], P = 0.98). Of the 1105 patients in the rhTM group, 554 were in the trial group and 551 were in the control group across four randomized controlled trials. The trial group showed a greater rate of DIC resolution than the control group (OR = 1.76 [1.34, 2.30], P < 0.0001), although there was no significant difference in the 28-day mortality rate or bleeding-related adverse events. (OR = 0.79 [0.59, 1.05], P = 0.11; OR = 1.08 [0.63, 1.86], P = 0.78).

CONCLUSION

Both AT and rhTM therapy improved the rate of symptomatic relief in patients with DIC without increasing the risk of bleeding, but there was no benefit in terms of their mortality.

Effectiveness and safety of antithrombin for treatment of portal vein thrombosis: Nationwide prospective surveillance of 4 years of clinical experience in Japan

AIM

Antithrombin (AT), a plasma protein with anticoagulant properties, has a long-standing medical history, primarily for treatment of congenital AT deficiency. Accumulated clinical experiences suggest AT is a potential anticoagulant for thrombotic diseases. This study aimed to clarify the effectiveness, safety, and clinical significance of AT in portal vein thrombosis (PVT) treatment in clinical practice in Japan, particularly in liver cirrhosis, where bleeding tendencies are increased.

METHODS

This prospective, observational post-marketing surveillance study assessed effectiveness and safety of AT in patients with PVT. Data were collected through electronic case report forms at medical institutions across Japan (from February 2018 to January 2021).

RESULTS

Of 680 patients, cirrhosis was the most prevalent underlying disease (79.7%), and the use of concomitant anticoagulants was common (62.8%). In the effectiveness analysis set (N = 477), overall improvement rate after AT administration was 51.2%, reaching 54.1% in patients with class C (severe) cirrhosis. Factors influencing clinical response included AT activity, Child-Pugh score, number of treatment courses, cause of thrombus, and thrombus obstruction. Responders showed a lower cumulative mortality rate versus nonresponders (18.3% vs. 27.6%; p = 0.013); 1-year recurrence rate among responders was 19.3%. In the safety analysis set (N = 680), bleeding events occurred in 5.15% of patients, with 1.32% having major bleeding events.

CONCLUSIONS

AT showed promise as an anticoagulant for high-risk PVT cases, especially in liver cirrhosis. Further well-designed comparative studies are needed to verify its efficacy in terms of true endpoints, such as long-term prognosis or improvement in cirrhosis.

Clinical Phenotype and Genetic Analysis of a Family with Hereditary Antithrombin Deficiency Caused by SERPINC1 Gene Mutation

Inherited deficiency of the antithrombin (hereditary antithrombin deficiency, AT deficiency, OMIM #613118) is a relatively rare (1:2,000-3,000) autosomal-dominant disorder with high risk of venous thromboembolism. The molecular basis of this condition has not yet fully understood, highlighting the need for further research to elucidate the underlying pathological mechanisms.This study aimed to investigate coagulation parameters and genetic phenotypes in a proband with hereditary antithrombin deficiency and her family members. Additionally, the investigation sought to provide preliminary insights for the molecular pathogenesis of this condition.Blood coagulation parameters, including plasma antithrombin activity (AT:A), antithrombin antigen (AT:Ag), protein C activity (PC:A), and protein S activity (PS:A) were measured in the peripheral blood of each family member by a Stago instrument. Peripheral blood was also extracted and sequenced to identify possible genetic mutation sites. The functional impact of variants on protein was subsequently analyzed by bioinformatics software.The proband, her mother, and brother all exhibited decreased activity and antigen of AT but normal PC and PS activity. The proband's father had normal activity and antigen levels of AT, PC, and PS. Sequencing revealed the proband's mother inherited the SERPINC1:c.661T > C,p.(Trp221Arg) heterozygous variant and her father harbored PROC:c.572_574del,p.(Lys193del) heterozygous variant while the proband as well as her brother carried both. Conservation analysis revealed that Trp221 is highly conserved across homologous species. Bioinformatics tools consistently classify the p.Trp221Arg mutation as "pathogenic" or "deleterious." Protein modeling indicated that the p.Trp221Arg variant does not alter the protein structure but may modify glycosylation sites to affect its function.The proband and family members exhibited varying degrees of decreased levels of AT and thrombosis, which were closely associated with inheritance of SERPINC1:c.661T > C,p.(Trp221Arg).

The concept of immunothrombosis in pancreas transplantation

Early failure of a pancreatic allograft due to complete thrombosis has an incidence of approximately 10% and is the main cause of comorbidity in pancreas transplantation. Although several risk factors have been identified, the exact mechanisms leading to this serious complication are still unclear. In this review, we define the roles of the individual components involved during sterile immunothrombosis-namely endothelial cells, platelets, and innate immune cells. Further, we review the published evidence linking the main risk factors for pancreatic thrombosis to cellular activation and vascular modifications. We also explore the unique features of the pancreas itself: the vessel endothelium, specific vascularization, and relationship to other organs-notably the spleen and adipose tissue. Finally, we summarize the therapeutic possibilities for the prevention of pancreatic thrombosis depending on the different mechanisms such as anticoagulation, anti-inflammatory molecules, endothelium protectors, antagonism of damage-associated molecular patterns, and use of machine perfusion.

THE INTERACTION BETWEEN ANTITHROMBIN AND ENDOTHELIAL HEPARAN SULFATE MITIGATES PULMONARY THROMBOINFLAMMATION AFTER TRAUMA AND HEMORRHAGIC SHOCK

ABSTRACT

Introduction : Trauma and hemorrhagic shock (T/HS) are associated with multiple organ injury. Antithrombin (AT) has anti-inflammatory and organ protective activity through its interaction with endothelial heparan sulfate containing a 3- O -sulfate modification. Our objective was to examine the effects of T/HS on 3- O -sulfated (3-OS) heparan sulfate expression and determine whether AT-heparan sulfate interactions are necessary for its anti-inflammatory properties. Methods : Male Sprague-Dawley rats underwent laparotomy, gut distension and fixed-pressure hemorrhagic shock (HS) and resuscitation. Liquid chromatography-coupled mass spectrometry analyses were performed to measure pulmonary and plasma heparan sulfate di/tetrasaccharides. Pulmonary mRNA levels were assessed by nCounter panel. Rats were treated with vehicle or surfen (1 mg/kg), a small molecule heparan sulfate antagonist, to block the interaction between AT and endothelial cells prior to T/HS and resuscitated with fresh frozen plasma (FFP), lactated Ringer's (LR), or AT-supplemented LR. Lung injury was assessed histologically for injury and fibrin deposition and immunostained for myeloperoxidase (MPO). Plasma was assessed for circulating inflammatory biomarkers. Results: T/HS significantly reduced pulmonary expression of 6- O and 3- O sulfated heparan sulfate, which was associated with reduced pulmonary 6- O - and 3- O -sulfotransferase mRNA levels. Surfen increased fibrin deposition and inflammatory cell infiltration into pulmonary tissue in T/HS rats resuscitated with FFP but had no effect in LR resuscitated rats. Although T/HS and LR resuscitation worsened histologic lung injury compared to sham, regardless of surfen treatment, lung injury was notably improved in FFP-resuscitated rodents pretreated with vehicle but not surfen. Surfen abrogated the anti-inflammatory effects of FFP, indicated by notable increases in circulating levels of multiple proinflammatory mediators compared to rats pretreated with vehicle. Finally, we observed significant increases in pulmonary fibrin and MPO staining in rats pretreated with surfen followed by resuscitation with LR supplemented with AT compared to vehicle, which was associated with notable increases in lung injury scores. Conclusions: T/HS causes pronounced reductions in pulmonary expression of 3-OS heparan sulfate, which is essential to AT's antithrombotic and anti-inflammatory activity. Blocking the interaction between AT and the endothelium attenuates the antithromboinflammatory and organ protective properties of FFP, suggesting that AT-endothelial anticoagulant function and anti-inflammatory signaling is important for organ protection during T/HS.

Antithrombin: Deficiency, Diversity, and the Future of Diagnostics

Our healthcare system provides reactive sick-care, treating patients after symptoms have appeared by prescription of generic and often suboptimal therapy. This strategy brings along high costs and high pressure which is not sustainable. Alternatively, P5 healthcare is proposed focusing on five key elements: prevention, personalization, prediction, participation, psychocognition, however, changes in current clinical care pathways are required, for which antithrombin deficiency is a prime example. Hereditary antithrombin deficiency (ATD) is a genetic disorder, for which screening is instigated after a thrombotic episode. Current diagnostic tests for ATD lack sensitivity and refinement to correctly classify patients, and generic treatments are prescribed. A molecular understanding of ATD through a molecular diagnostic test that analyzes all clinically relevant features of antithrombin is required. Here, clinically relevant molecular characteristics of antithrombin, the diversity of antithrombin (deficiency) in heath and disease, and the strengths and weaknesses of antithrombin tests are reviewed. A mass spectrometry test that molecularly characterizes a patients antithrombin proteoforms harbors the highest potential to improve the clinical pathway for ATD. Application of this MS-based test in a future enhanced clinical pathway will improve patient management and outcome through molecular characterization of antithrombin and enables the promise of P5 healthcare for ATD.

Expanding the Role of Heparin Derivatives in Oncology: From Anticoagulation to Antitumor Activity

Current research demonstrates the expanding therapeutic potential of heparin derivatives in oncology, extending beyond traditional anticoagulation mechanisms. This systematic analysis examines the structural characteristics, molecular mechanisms, and therapeutic applications of heparin-based compounds in malignancy treatment. The essential antithrombin binding pentasaccharide sequence has enabled development of specialized molecular variants, particularly fractionated heparins and their non-anticoagulant counterparts. These agents exert antineoplastic effects via multiple pathways, particularly through modulation of heparanase enzymatic activity and specific protein-glycosaminoglycan interactions. Evidence from pivotal clinical trials (FRAGMATIC, MAGNOLIA, GASTRANOX) confirms efficacy in managing cancer-associated thrombosis while indicating potential enhancement of chemotherapeutic outcomes. The preparation methods utilize enzymatic cleavage reactions and selective chemical derivatization to generate structurally modified heparins exhibiting unique molecular characteristics and biological activities. Analysis of the glycosaminoglycan analog dociparstat sodium reveals significant activity in myeloid malignancies, mediated by specific interference with CXCL12/CXCR4 signaling cascades. Significant challenges remain in manufacturing scale-up, analytical validation, and long-term safety assessment. Future studies must address dose optimization, combination strategies, and controlled clinical trials to determine the full therapeutic potential of these compounds in clinical oncology.

Glycosaminoglycans, Instructive Biomolecules That Regulate Cellular Activity and Synaptic Neuronal Control of Specific Tissue Functional Properties

Glycosaminoglycans (GAGs) are a diverse family of ancient biomolecules that evolved over millennia as key components in the glycocalyx that surrounds all cells. GAGs have molecular recognition and cell instructive properties when attached to cell surface and extracellular matrix (ECM) proteoglycans (PGs), which act as effector molecules that regulate cellular behavior. The perception of mechanical cues which arise from perturbations in the ECM microenvironment allow the cell to undertake appropriate biosynthetic responses to maintain ECM composition and tissue function. ECM PGs substituted with GAGs provide structural support to weight-bearing tissues and an ability to withstand shear forces in some tissue contexts. This review outlines the structural complexity of GAGs and the diverse functional properties they convey to cellular and ECM PGs. PGs have important roles in cartilaginous weight-bearing tissues and fibrocartilages subject to tension and high shear forces and also have important roles in vascular and neural tissues. Specific PGs have roles in synaptic stabilization and convey specificity and plasticity in the regulation of neurophysiological responses in the CNS/PNS that control tissue function. A better understanding of GAG instructional roles over cellular behavior may be insightful for the development of GAG-based biotherapeutics designed to treat tissue dysfunction in disease processes and in novel tissue repair strategies following trauma. GAGs have a significant level of sophistication over the control of cellular behavior in many tissue contexts, which needs to be fully deciphered in order to achieve a useful therapeutic product. GAG biotherapeutics offers exciting opportunities in the modern glycomics arena.

Emerging Therapies in Hemophilia: Improving Equitable Access to Care

In recent years, gene therapy and bio-engineered hemostatic molecules have revolutionized treatment for people with hemophilia. These innovative therapies aim to decrease treatment burden and improve patient quality of life. Additional novel therapies, including next-generation mimetics and agents that rebalance hemostasis, are currently being evaluated in clinical trials. Technological advances such as point-of-care musculoskeletal ultrasound and artificial intelligence may improve patient diagnostic and treatment outcomes. However, for the majority of patients with hemophilia worldwide, diagnosis and effective treatment are inaccessible. Achieving health equity for all hemophilia patients requires improved identification of barriers to optimal care, including socioeconomic status, race/ethnicity, gender, disease severity, inhibitor status, age, and use of Hemophilia Treatment Centers. Access to novel hemophilia therapies should be ensured for all patients. Approaches to improving equity include a decision-making partnership between the patient and clinician, stakeholder engagement, and pharmaceutical industry support. The development of novel hemophilia therapies should be leveraged with a patient-centered care approach to improve health equity for all patients.

The Mechanisms of Sepsis Induced Coagulation Dysfunction and Its Treatment

Sepsis is a critical condition characterized by organ dysfunction due to a dysregulated response to infection that poses significant global health challenges. Coagulation dysfunction is nearly ubiquitous among sepsis patients. Its mechanisms involve platelet activation, coagulation cascade activation, inflammatory reaction imbalances, immune dysregulation, mitochondrial damage, neuroendocrine network disruptions, and endoplasmic reticulum (ER) stress. These factors not only interact but also exacerbate one another, leading to severe organ dysfunction. This review illustrates the mechanisms of sepsis-induced coagulopathy, with a focus on tissue factor activation, endothelial glycocalyx damage, and the release of neutrophil extracellular traps (NETs), all of which are potential targets for therapeutic interventions.

Disseminated intravascular coagulation: cause, molecular mechanism, diagnosis, and therapy

Disseminated intravascular coagulation (DIC) is a complex and serious condition characterized by widespread activation of the coagulation cascade, resulting in both thrombosis and bleeding. This review aims to provide a comprehensive overview of DIC, emphasizing its clinical significance and the need for improved management strategies. We explore the primary causes of DIC, including sepsis, trauma, malignancies, and obstetric complications, which trigger an overactive coagulation response. At the molecular level, DIC is marked by excessive thrombin generation, leading to platelet and fibrinogen activation while simultaneously depleting clotting factors, creating a paradoxical bleeding tendency. Diagnosing DIC is challenging and relies on a combination of existing diagnostic criteria and laboratory tests. Treatment strategies focus on addressing the underlying causes and may involve supportive care, anticoagulation therapy, and other supportive measures. Recent advances in understanding the pathophysiology of DIC are paving the way for more targeted therapeutic approaches. This review highlights the critical need for ongoing research to enhance diagnostic accuracy and treatment efficacy, ultimately improving patient outcomes in those affected by DIC.

Factor VIIa-Antithrombin Complexes are Increased in Asthma: Relation to the Exacerbation-Prone Asthma Phenotype

BACKGROUND

 Asthma is associated with a prothrombotic state. Plasma factor VIIa-antithrombin complex (FVIIa-AT) concentrations indirectly reflect the interaction of tissue factor (TF) with FVII. Since TF is a key initiator of coagulation in vivo, we hypothesized that FVIIa-AT concentrations are higher in asthma.

METHODS

 In 159 clinically stable adult asthma patients and 62 controls, we determined FVIIa-AT in plasma and analyzed their relation to circulating inflammatory and prothrombotic markers together with the total plasma potential for fibrinolysis (clot lysis time, CLT) and thrombin generation. We recorded clinical outcomes, including asthma exacerbations, during 3-year follow-up.

RESULTS

 Asthma patients were characterized by 38.5% higher FVIIa-AT (p < 0.001), related to bronchial obstruction (FEV1: r = -0.397, p < 0.001), asthma severity (r = 0.221, p = 0.005), and duration (r = 0.194, p = 0.015) compared to controls. FVIIa-AT showed weak positive associations with C-reactive protein (r = 0.208, p = 0.009), fibrinogen (r = 0.215, p = 0.007), and CLT (r = 0.303, p < 0.001) but not with thrombin generation parameters. In the follow-up (data obtained from 151 patients), we documented 151 severe asthma exacerbations in 51 (33.8%) patients, including 33 (21.9%) with ≥2 such events. Exacerbation-prone asthma phenotype was related to 13.1% higher FVIIa-AT (p = 0.012), along with asthma severity and control (p < 0.003, both). High FVIIa-AT (that is ≥100.1 pmol/L), defined on receiver operating characteristic curves, was linked to exacerbation-prone asthma phenotype (odds ratio 1.85; 95%CI: 1.23-2.80, p = 0.003) and shorter time to first exacerbation (p = 0.023).

CONCLUSION

 This study is the first to show that FVIIa-AT concentrations are higher in asthma in relation to its severity and may help identify individuals at risk of the exacerbation-prone asthma phenotype.

The value of thrombus markers applied in patients with respiratory failure

Background

This work assessed the value of novel thrombus markers-thrombin-antithrombin complex (TAT), plasmin-a2-plasmin inhibitor complex (PIC), thrombomodulin (TM), and tissue plasminogen activator-inhibitor complex (t-PAIC) applied in patients with respiratory failure (RF), including their role in predicting thrombus formation, evaluating prognosis, and assessing disease severity.

Methods

Eighty patients with RF were enrolled and categorized into mild (n = 10), moderate (n = 9), and severe (n = 71) groups based on disease severity. Meanwhile, patients were also classified into thrombus (n = 14) and non-thrombus (n = 76) groups based on the presence of thrombus. Furthermore, they were assigned into survival (n = 70) and death (n = 20) groups based on prognosis. Traditional coagulation indicators, thrombus markers, infection-related parameters, and respiratory-related indicators were compared among patients in different groups. This work explored the predictive effects of these indicators on the degree of respiratory failure, thrombus formation, and prognosis in various patient groups. Additionally, correlations of thrombus markers and traditional coagulation indicators to respiratory-related indicators and infectionrelated indicators were analyzed.

Results

Upon admission, levels of thrombin-antithrombin complex (TAT), plasmin-a2-plasmin inhibitor complex (PIC), and tissue plasminogen activator-inhibitor complex (t-PAIC) in the thrombus group were sharply higher in contrast to those in the non-thrombus group, showing obvious differences (P<0.05). Patients in the death group experienced remarkably elevated TAT, PIC, t-PAIC, thrombomodulin (TM), and to the survival group (P<0.05). In addition, high-sensitivity C-reactive protein (hs-CRP) in the death group was higher to that in the survival group (P<0.05). Platelet count (PLT) and procalcitonin (PCT) were sharply lower in the survival group (P<0.05). In groups of varying severity, PCT exhibited an elevated level in the severe, demonstrating great differences to the mild to moderate groups (P<0.05). Besides, TAT, PIC, TM, and t-PAIC showed higher sensitivity and accuracy in predicting severe RF, with higher specificity in predicting thrombus formation in RF patients. In correlation analysis, a positive correlation was observed between TT, PCT, and the fraction of inspired oxygen (FiO2). The activated partial thromboplastin time (APTT), PCT, and FiO2 exhibited positive correlations. Additionally, a positive association existed between fibrinogen (FIB), hs-CRP, and PLT. A positive link was identified between D-dimer and hs-CRP, PIC and PLT, as well as tPAIC and PCT.

Conclusions

Thrombus markers exerted a crucial effect in patients experiencing respiratory failure, serving as pivotal indicators for assessing the severity of the condition, identifying thrombotic risk, and predicting prognosis.

Classification and characteristics of bacterial glycosaminoglycan lyases, and their therapeutic and experimental applications

Glycosaminoglycans (GAGs), as animal polysaccharides, are linked to proteins to form various types of proteoglycans. Bacterial GAG lyases are not only essential enzymes that spoilage bacteria use for the degradation of GAGs, but also valuable tools for investigating the biological function and potential therapeutic applications of GAGs. The ongoing discovery and characterization of novel GAG lyases has identified an increasing number of lyases suitable for functional studies and other applications involving GAGs, which include oligosaccharide sequencing, detection and removal of specific glycan chains, clinical drug development and the design of novel biomaterials and sensors, some of which have not yet been comprehensively summarized. GAG lyases can be classified into hyaluronate lyases, chondroitinases and heparinases based on their substrate spectra, and their functional applications are mainly determined by their substrates, with different lyases exhibiting differing substrate selectivity and preferences. It is thus necessary to understand the properties of the available enzymes to determine strategies for their functional application. Building on previous studies and reviews, this Review highlights small yet crucial differences among or within the various GAG lyases to aid in optimizing their use in future studies. To clarify ideas and strategies for further research, we also discuss several traditional and novel applications of GAG lyases.

Advances in Development of Drug Treatment for Hemophilia with Inhibitors

Patients with hemophilia A and B who have inhibitors face limited treatment options, because replacement therapy with clotting factor VIII or IX concentrates is ineffective, particularly for patients with high-titer inhibitors. Current mainstay therapies include immune tolerance induction (through frequent injections of clotting factor VIII or IX concentrates) to eradicate inhibitors and bypassing agents (such as recombinant activated clotting factor VII and activated prothrombin complex concentrates) for the prevention and treatment of bleeding episodes. The use of these agents typically requires intravenous injections and sometimes hospitalization, which can be burdensome for patients. More recently, emicizumab, a bispecific antibody that mimics the function of activated clotting factor VIII, has demonstrated favorable efficacy for prophylaxis in patients with hemophilia A and inhibitors, representing a promising new therapeutic strategy. Ongoing research aims to discover and develop easy-to-use nonfactor agents for managing hemophilia with inhibitors. This review summarizes the current understanding of the pathophysiology of inhibitor development in hemophilia, outlines existing treatment options, and discusses advancements in novel therapeutic biologics, including a recombinant activated clotting factor VII variant (marzeptacog alfa), a new bispecific antibody (Mim8), antitissue factor pathway inhibitor antibodies (concizumab and marstacimab), and small interfering RNA targeting antithrombin (fitusiran). All of these agents are administered subcutaneously, with some offering the convenience of less frequent dosing (e.g., weekly or monthly). These potential drug candidates may provide significant benefits for the prophylaxis or treatment of bleeding disorders in patients with hemophilia and inhibitors.

Cure of Congenital Purpura Fulminans via Expression of Engineered Protein C Through Neonatal Genome Editing in Mice

BACKGROUND

PC (protein C) is a plasma anticoagulant encoded by PROC; mutation in both PROC alleles results in neonatal purpura fulminans-a fatal systemic thrombotic disorder. In the present study, we aimed to develop a genome editing treatment to cure congenital PC deficiency.

METHODS

We generated an engineered APC (activated PC) to insert a furin-cleaving peptide sequence between light and heavy chains. The engineered PC was expressed in the liver of mice using an adeno-associated virus vector or CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeat-associated 9)-mediated genome editing using an adeno-associated virus vector in vivo.

RESULTS

The engineered PC could be released in its activated form and significantly prolonged the plasma coagulation time independent of the cofactor activity of PS (protein S) in vitro. The adeno-associated virus vector-mediated expression of the engineered PC, but not wild-type PC, prolonged coagulation time owing to the inhibition of activated coagulation FV (factor V) in a dose-dependent manner and abolished pathological thrombus formation in vivo in C57BL/6J mice. The insertion of EGFP (enhanced green fluorescent protein) sequence conjugated with self-cleaving peptide sequence at Alb locus via neonatal in vivo genome editing using adeno-associated virus vector resulted in the expression of EGFP in 7% of liver cells, mainly via homology-directed repair, in mice. Finally, we succeeded in improving the survival of PC-deficient mice by expressing the engineered PC via neonatal genome editing in vivo.

CONCLUSIONS

These results suggest that the expression of engineered PC via neonatal genome editing is a potential cure for severe congenital PC deficiency.

Prospective Application of Mesenchymal Stem Cell-Derived Exosomes in the Treatment of Disseminated Intravascular Coagulation

Disseminated intravascular coagulation (DIC) is an acquired disorder characterized by systemic activation of blood coagulation, which can arise from various causes. Owing to its abrupt onset, rapid progression, and high mortality rate, DIC presents a major clinical challenge. Anticoagulant drugs, such as heparin or low-molecular-weight heparin, are the current gold standard of treatment; however, these interventions pose considerable bleeding risks. Thus, safer and more effective therapeutic strategies are urgently required. Owing to their strong anti-inflammatory and tissue repair capabilities, mesenchymal stem cell-derived exosomes (MSC-Exos) have gained considerable attention as novel therapeutic options for numerous disorders, including DIC. Their stability in diverse pathological states highlights their potential as promising candidates for DIC therapy. This review presents the latest insights on the pathogenesis of DIC and anti-inflammatory and anticoagulant properties of MSC-Exos. We aimed to elucidate the potential mechanisms by which MSC-Exos influence DIC pathogenesis. We speculate that MSC-Exos offer a multifaceted approach to DIC treatment by attenuating neutrophil extracellular trap formation, modulating M1/M2 macrophage polarization, altering Nrf2/NF-κB signalling pathway to downregulate pro-inflammatory factors, and correcting imbalances in the coagulation-fibrinolysis system through anticoagulant routes. This suggests that MSC-Exos are a potential paradigm in DIC therapy, offering novel targets and treatment modalities for DIC management.

Good metabolic control is associated with decreased circulating factor VIIa- antithrombin complexes in type 2 diabetes: a cross-sectional study

BACKGROUND

Diabetes is associated with a prothrombotic state that contributes to cardiovascular (CV) events in type 2 diabetes (T2DM). Activated factor VII (FVIIa)- antithrombin (AT) complexes are indicative of tissue factor (TF) exposure and have been associated with thromboembolic risk in coronary artery disease. To our knowledge there have been no reports on FVIIa-AT complexes in T2DM, therefore we assessed factors that determine FVIIa-AT complexes in this disease and the impact of higher complexes on a prothrombotic state.

METHODS

In 108 T2DM patients (mean age 63.8 years, 52.8% men, median HbA1c of 6.9 [interquartile range 6.1-8.2] %) and 83 age- and sex-matched non-diabetic subjects, we measured FVIIa-AT complexes. Metabolic control of T2DM involved fasting glucose, glycated hemoglobin (HbA1c), albumin/creatinine ratio (ACR), and lipid levels. To characterize a prothrombotic state, we determined thrombin generation parameters, fibrinolysis markers, and plasma fibrin clot properties.

RESULTS

FVII-AT complexes in T2DM patients were similar to controls (73.6 [59.4-91.7] vs. 79.6 [59.2-97.1]pM, respectively, p = 0.30). The T2DM patients with FVIIa-AT in the top vs. the bottom quartile had a larger prevalence of active smoking and insulin use, along with higher fasting glucose (+ 36.4%), HbA1c (+ 27.4%), ACR (+ 72.8%), total cholesterol (+ 34.5%), and LDL-cholesterol (+ 80%). FVIIa-AT complexes showed no associations with in vitro thrombin generation potential, plasma fibrin clot properties, or fibrinolysis variables. On multivariable analysis HbA1c, ACR, and total cholesterol remained independently associated with FVIIa-AT complexes in T2DM.

CONCLUSIONS

This is the first study to show that in T2DM higher FVIIa-AT complexes are associated with markers of dyslipidemia and glycemia control, indicating that TF-induced coagulation activation could be suppressed by achieving treatment targets.

Thrombophilia Screening: Not So Straightforward

Although inherited thrombophilias are lifelong risk factors for a first thrombotic episode, progression to thrombosis is multifactorial and not all individuals with inherited thrombophilia develop thrombosis in their lifetimes. Consequently, indiscriminate screening in patients with idiopathic thrombosis is not recommended, since presence of a thrombophilia does not necessarily predict recurrence or influence management, and testing should be selective. It follows that a decision to undertake laboratory detection of thrombophilia should be aligned with a concerted effort to identify any significant abnormalities, because it will inform patient management. Deficiencies of antithrombin and protein C are rare and usually determined using phenotypic assays assessing biological activities, whereas protein S deficiency (also rare) is commonly detected with antigenic assays for the free form of protein S since available activity assays are considered to lack specificity. In each case, no single phenotypic assay is capable of detecting every deficiency, because the various mutations express different molecular characteristics, rendering thrombophilia screening repertoires employing one assay per potential deficiency, of limited effectiveness. Activated protein C resistance (APCR) is more common than discrete deficiencies of antithrombin, protein C, and protein S and also often detected initially with phenotypic assays; however, some centres perform only genetic analysis for factor V Leiden, as this is responsible for most cases of hereditary APCR, accepting that acquired APCR and rare F5 mutations conferring APCR will go undetected if only factor V Leiden is evaluated. All phenotypic assays have interferences and limitations, which must be factored into decisions about if, and when, to test, and be given consideration in the laboratory during assay performance and interpretation. This review looks in detail at performance and limitations of routine phenotypic thrombophilia assays.

Tissue factor pathway inhibitor - cofactor-dependent regulation of the initiation of coagulation

PURPOSE OF REVIEW

In humans, tissue factor pathway inhibitor (TFPI) exists in two alternatively spliced isoforms, TFPIα and TFPIβ. TFPIα consists of three Kunitz domains (K1, K2 and K3) and a highly basic C-terminal tail. K1 inhibits the tissue factor-activated factor VII complex, K2 specifically inhibits activated factor X, K3 is essential for interaction with its cofactor, protein S, and the basic C-terminus is binds factor V-short (FV-short) with high affinity. TFPIβ consists of K1 and K2 that is glycosylphosphatidylinositol anchored directly to cell surfaces. This review explores the structure/function of TFPI and its cofactors (protein S and FV-short), and the relative contributions that different TFPI isoforms may play in haemostatic control.

RECENT FINDINGS

Recent data have underscored the importance of TFPIα function and its reliance on its cofactors, protein S and FV-short, in influencing haemostatic control as well as bleeding and thrombotic risk.

SUMMARY

TFPIα is likely the most important pool of TFPI in modifying the risk of thrombosis and bleeding. TFPIα forms a trimolecular complex with FV-short and protein S in plasma. FV-short expression levels control the circulating levels of TFPIα, whereas protein S exerts essential cofactor mediated augmentation of it anticoagulant function.

Back to basics: the coagulation pathway

The classic coagulation cascade model of intrinsic and extrinsic coagulation pathways, i.e. contact activation pathway and tissue factor pathway, has been widely modified. The cascade can be categorized as follows: 1) initiation by tissue factor (TF), 2) amplification by the intrinsic tenase complex, and 3) propagation on activated platelets. TF-FVIIa forms an extrinsic tenase complex and activates FX to FXa and FIX to FIXa. FXa-FVa forms a prothrombinase complex that converts prothrombin into thrombin. At this initial stage of coagulation, only small amounts of thrombin are generated owing to the low circulating levels of FVa. The generated thrombin, although in minor quantities, is sufficient to prime the subsequent coagulation reactions. Platelets and in turn FV, FVIII, and FXI are activated. Subsequently, FVIIIa binds to FIXa to form the intrinsic tenase complex, which is aided by a cofactor, FVIIIa, and activates FX at a rate 50-times higher than that of the extrinsic tenase complex, thereby amplifying thrombin generation. Thrombin cleaves fibrinogen into one fibrin monomer and two fibrinopeptides. Fibrin monomers aggregate, crosslink, and branch into an insoluble fibrin network structure. The contact activation system is initiated by FXII, which is activated upon exposure to negatively charged surfaces. Coagulation is driven by FXIIa-mediated FXI cleavage. FXIa activates FIX, which forms an intrinsic tenase complex, eventually leading to thrombin formation. The contact activation system is considered to contribute to thrombosis but is not required for hemostasis in vivo.

Blood hypercoagulability and thrombosis mechanisms in cancer patients -A brief review

Patients with malignant tumors are prone to present hypercoagulability of blood and form thrombosis, and its pathogenesis is complex involving various factors from clinical and histopathological to genetic influences. Current studies on the potential mechanism of blood hypercoagulability in patients with malignant tumors focus on the following aspects but are not limited: (1) tumor cells release coagulant-promoting substances, (2) tumor cells interact with the fibrinolytic system, (3) tumor cell-mediated platelet activation, (4) tumor-associated complement activation, and (5) genetic factors and clinical factors. Especially, the pathogenesis of blood hypercoagulability is in-depth analyzed covering tumor cells' release of procoagulant substances, the interplay of cancer cells and fibrinolytic system, platelet activation mediated by cancer cells, cancer-associated complement activation, and the action of genetic and clinical factors. We review the pathogenesis of blood hypercoagulability in patients with malignant tumors, which will assist in the research and development of new drugs and providing theoretical support for the formulation of the best treatment plan for patients, to prolong the survival of patients.

Innovative Substrate Design with Basement Membrane Components for Enhanced Endothelial Cell Function and Endothelization

Enhancing endothelial cell growth on small-diameter vascular grafts produced from decellularized tissues or synthetic substrates is pivotal for preventing thrombosis. While optimized decellularization protocols can preserve the structure and many components of the extracellular matrix (ECM), the process can still lead to the loss of crucial basement membrane proteins, such as laminin, collagen IV, and perlecan, which are pivotal for endothelial cell adherence and functional growth. This loss can result in poor endothelialization and endothelial cell activation causing thrombosis and intimal hyperplasia. To address this, the basement membrane's ECM is emulated on fiber substrates, providing a more physiological environment for endothelial cells. Thus, fibroblasts are cultured on fiber substrates to produce an ECM membrane substrate (EMMS) with basement membrane proteins. The EMMS then underwent antigen removal (AR) treatment to eliminate antigens from the membrane while preserving essential proteins and producing an AR-treated membrane substrate (AMS). Subsequently, human endothelial cells cultured on the AMS exhibited superior proliferation, nitric oxide production, and increased expression of endothelial markers of quiescence/homeostasis, along with autophagy and antithrombotic factors, compared to those on the decellularized aortic tissue. This strategy showed the potential of pre-endowing fiber substrates with a basement membrane to enable better endothelization.

Nattokinase as an adjuvant therapeutic strategy for non-communicable diseases: a review of fibrinolytic, antithrombotic, anti-inflammatory, and antioxidant effects

INTRODUCTION

Nattokinase (NK) is the primary ingredient of natto, a traditional Asian food made from fermented soybean by Bacillus subtilis natto. Studies have shown that natto reduces the risk of cardiovascular disease (CVD) mortality due to its fibrinolytic and antithrombotic properties. A new field of studies also demonstrates that NK can mitigate molecular pathways related to inflammation and oxidative stress and can be considered an adjuvant strategy for use in many non-communicable diseases (NCDs). This paper is a narrative review of the literature. A search was conducted in PubMed and ScienceDirect up to July 2024.

AREAS COVERED

This review discusses the possible effects of NK on mitigating the common complications of NCDs, such as inflammation and oxidative stress. In addition, it provides an update on the most addressed areas related to NK's fibrinolytic and antithrombotic activities.

EXPERT OPINION

Due to the fibrinolytic and antithrombotic activity of nattokinase, and more recently added to the anti-inflammatory and antioxidant effects, this enzyme can be used as a new adjuvant therapeutic strategy to mitigate inflammation and oxidative stress in NCDs, including CVD.

Heparin-Bead Extraction Enhanced Fluorogenic Aptamer-Thrombin Composite Reporter Enables Sensitive and Rapid Detection of Functional Antithrombin

Antithrombin (AT) deficiency in the extracorporeal circulation during cardiac surgery leads to uncontrolled inflammation and vascular damage in patients. AT levels decrease in sepsis, major trauma, extracorporeal membrane oxygenation, and eclampsia. Monitoring plasma AT levels facilitates the accurate restoration of AT to baseline values through precise supplementation. Traditional methods of chromogenic assay and enzyme-linked immunosorbent assay (ELISA) kits encounter challenges, such as interference, inconsistency, and delayed response times, making real-time, reliable antithrombin monitoring a clinical gap. To address this critical need, we develop a heparin-bead extraction enhanced fluoroGenic aptamer-thrombin composite reporter (HExGATOR) for the rapid, sensitive, and precise detection of functional AT in plasma. Our design employs thrombin-binding aptamers and a fluorescence "turn on" technology such that a signal is produced upon the interaction of AT with the otherwise "turned off" aptamer-thrombin complex. The prominent signal-background interference originating from plasma is remarkably diminished by using a heparin-bead solid-phase extraction of AT. We achieved highly sensitive and rapid detection of AT in 5 to 20 min with a limit of detection of 15.11 nM. This approach offers a promising alternative to traditional AT tests in clinical settings, potentially facilitating personalized anticoagulant therapy.

Antithrombin testing and treatment in pregnancy: Their real-world relationship to clinical outcomes

BACKGROUND

Antithrombin (AT) deficiency is a severe thrombophilia associated with increased rates of maternal morbidity, mortality, and greater healthcare resource utilization during pregnancy and postpartum.

METHODS

Two large U.S. healthcare databases were queried for women aged 15-44 with delivery-related encounters: Cerner Real-World Data (CRWD, 01/01/2000-12/31/2021) and Premier Healthcare Database (PHD, 01/01/2016-01/01/2019). Individuals receiving cardiopulmonary bypass were excluded. Three cohorts were created: 1) Individuals who had AT levels tested any time between 9-months pre- through 3-months post-delivery (CRWD Test Cohort); 2) individuals prescribed AT concentrate (ATc) within 1-year pre- or 1-year post-delivery in CRWD (CRWD Medication Cohort); and 3) the same criteria as 2) applied to PHD (PHD Medication Cohort).

RESULTS

There were 5411 individuals in the CRWD Test Cohort, 13 in the CRWD Medication Cohort and 38 in the PHD Medication Cohort. Demographic and baseline clinical characteristics were similar across cohorts. AT level testing occurred pre-delivery in 47.9 % of the CRWD Test Cohort and 23.1 % of the CRWD Medication Cohort. ATc was administered during the delivery hospitalization to 0.1 %, 23.1 % and 50.0 % of the CRWD Test, CRWD Medication, and PHD Medication Cohorts, respectively. Across cohorts, 5.4-7.9 % of individuals experienced thrombosis during the delivery-related encounter. Mean (SD) total costs for delivery through 1-year post-delivery were $190,894 ($276,893) with $123,763 ($177,122) of total costs related to abnormal coagulation.

CONCLUSION

Opportunities exist to enhance the care of pregnant individuals with low AT levels throughout pregnancy, aiming for optimal maternal outcomes.

Association between rTMS-induced changes in inflammatory markers and improvement in psychiatric diseases: a systematic review

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) has recently gained relevance in treating different psychiatric disorders. Limited evidence suggests that the beneficial effects of rTMS on psychopathology could be at least partly mediated through changes in inflammatory response. This systematic review summarizes the literature on whether rTMS can modulate inflammatory markers and thus positively influence the course of psychiatric illnesses.

MATERIALS AND METHODS

A systematic review of rTMS and inflammatory markers in psychiatric diseases was conducted according to PRISMA guidelines. Information on the association between rTMS treatment response and changes of inflammatory markers was extracted. The quality of the studies was assessed using the National Heart, Lung, and Blood Institute for human studies and the Systematic Review Center for Laboratory Animal Experimentation for animal studies.

RESULTS

This review includes 17 studies (2 animal and 15 human studies) on the relationship between rTMS treatment response and changes of inflammatory markers. Positive changes in microglial activity and anti-inflammatory effects were associated with behavioral improvement in animal models of depression. However, these findings have not been consistently replicated in human studies focusing on treatment-resistant depression. While several studies reported rTMS-induced alterations in peripheral inflammatory markers, only two could demonstrate their association to clinical treatment response. Notably, most studies showed poor or moderate quality in the bias assessment.

CONCLUSIONS

While certain human studies suggest an association between rTMS-induced anti-inflammatory effects and improvement in psychopathology, heterogeneity, and underpowered analyses constrain the generalizability of these results. The discrepancy between animal and human findings highlights the need for larger, standardized human studies.

TRIAL REGISTRATION

(PROSPERO Registration: CRD42023492732).

Epigenetic Targeting of Heparan Sulfate 3-O- and 6-O-Sulfation in Breast Cancer Cells: Prospects for Attenuating Prothrombotic Tumor Cell Activities

The deregulation of cell surface heparan sulfate proteoglycans (HSPGs) is a main issue of cancer cells for increasing their malignancy. In these terms, the sulfation pattern of HS, created by an orchestrated activity of enzymes balancing a site-specific sulfation, is of key importance. These enzymes are often deregulated by epigenetic processes in cancer, e.g., being silenced by DNA hypermethylation. Here, we address this issue in human breast cancer cell lines aiming to target epigenetic processes to reactivate HS sulfation, shifting HS into an antithrombotic phenotype for which 3-O-sulfation is particularly important. Treatment of MCF-7 and MDA-MB-231 cells with nontoxic concentrations of 5-azacytidine (azacytidine) and 5-fluoro-2'-deoxycytidine (FdCyd) as DNMT inhibitors or vorinostat for targeting HDAC increased HS3-O-sulfation remarkably, as confirmed by fluorescence microscopy, by upregulating HS3-O-sulfotransferases, detected by quantitative real-time polymerase chain reaction and Western blot. Flow cytometry and microscopic approaches confirm that upon inhibitor treatment, increased HS3-O-sulfation improves cell binding to antithrombin, leading to an antithrombotic activity. Nevertheless, only azacytidine- and vorinostat-treated cells display anticoagulative properties, represented by attenuated thrombin formation, a lower activation of human platelet aggregation, or ATP release. In contrast, FdCyd additionally upregulated tissue factor expression in both cell lines, overshadowing the anticoagulant effects of HS, leading to an overall prothrombotic phenotype. Our data provide evidence for the first time that targeting epigenetic processes in HS sulfation is a valuable means to foster anticoagulative cell properties for decreasing malignancy and metastatic potency. These data warrant further investigations to fine-tune epigenetic targeting and to search for potential biomarkers attributed to these activities.

SerpinB3: A Multifaceted Player in Health and Disease-Review and Future Perspectives

SerpinB3, a member of the serine-protease inhibitor family, has emerged as a crucial player in various physiological and pathological processes. Initially identified as an oncogenic factor in squamous cell carcinomas, SerpinB3's intricate involvement extends from fibrosis progression and cancer to cell protection in acute oxidative stress conditions. This review explores the multifaceted roles of SerpinB3, focusing on its implications in fibrosis, metabolic syndrome, carcinogenesis and immune system impairment. Furthermore, its involvement in tissue protection from oxidative stress and wound healing underscores its potential as diagnostic and therapeutic tool. Recent studies have described the therapeutic potential of targeting SerpinB3 through its upstream regulators, offering novel strategies for cancer treatment development. Overall, this review underscores the importance of further research to fully elucidate the mechanisms of action of SerpinB3 and to exploit its therapeutic potential across various medical conditions.

Influence of Substrate Structure and Associated Properties on Endothelial Cell Behavior in the Context of Behaviors Associated with Laminar Flow Conditions

In order to treat most vascular diseases, arterial grafts are commonly employed for replacing small-diameter vessels, yet they often cause thrombosis. The growth of endothelial cells along the interior surfaces of these grafts (substrates) is critical to mitigate thrombosis. Typically, endothelial cells are cultured inside these grafts under laminar flow conditions to emulate the native environment of blood vessels and produce an endothelium. Alternatively, the substrate structure could have a similar influence on endothelial cell behavior as laminar flow conditions. In this study, we investigated whether substrates with aligned fiber structures could induce responses in human umbilical vein endothelial cells (HUVECs) akin to those elicited by laminar flow. Our observations revealed that HUVECs on aligned substrates displayed significant morphological changes, aligning parallel to the fibers, similar to effects reported under laminar flow conditions. Conversely, HUVECs on random substrates maintained their characteristic cobblestone appearance. Notably, cell migration was more significant on aligned substrates. Also, we observed that while vWF expression was similar between both substrates, the HUVECs on aligned substrates showed more expression of platelet/endothelial cell adhesion molecule-1 (PECAM-1/CD31), laminin, and collagen IV. Additionally, these cells exhibited increased gene expression related to critical functions such as proliferation, extracellular matrix production, cytoskeletal reorganization, autophagy, and antithrombotic activity. These findings indicated that aligned substrates enhanced endothelial growth and behavior compared to random substrates. These improvements are similar to the beneficial effects of laminar flow on endothelial cells, which are well-documented compared to static or turbulent flow conditions.

Mutual Inhibition of Antithrombin III and SARS-CoV-2 Cellular Attachment to Syndecans: Implications for COVID-19 Treatment and Vaccination

Antithrombin III (ATIII) is a potent endogenous anticoagulant that binds to heparan sulfate proteoglycans (HSPGs) on endothelial cells' surfaces. Among these HSPGs, syndecans (SDCs) are crucial as transmembrane receptors bridging extracellular ligands with intracellular signaling pathways. Specifically, syndecan-4 (SDC4) has been identified as a key receptor on endothelial cells for transmitting the signaling effects of ATIII. Meanwhile, SDCs have been implicated in facilitating the cellular internalization of SARS-CoV-2. Given the complex interactions between ATIII and SDC4, our study analyzed the impact of ATIII on the virus entry into host cells. While ATIII binds to all SDC isoforms, it shows the strongest affinity for SDC4. SDCs' heparan sulfate chains primarily influence ATIII's SDC attachment, although other parts might also play a role in ATIII's dominant affinity toward SDC4. ATIII significantly reduces SARS-CoV-2's cellular entry into cell lines expressing SDCs, suggesting a competitive inhibition mechanism at the SDC binding sites, particularly SDC4. Conversely, the virus or its spike protein decreases the availability of SDCs on the cell surface, reducing ATIII's cellular attachment and hence contributing to a procoagulant environment characteristic of COVID-19.

Interaction of Serum and Plasma Proteins with Polyelectrolyte Microparticles with Core/Shell and Shell-Only Structures

Polyelectrolyte microparticles (MPs) synthesized on calcium carbonate cores are considered a promising basis for new drug delivery systems. It is known that microparticles entering a physiological environment absorb proteins on their surface, which can change the properties of the microparticles and alter their functional activity. This study aimed to compare the compositions of the adsorbed protein layer formed on microparticles with the core/shell and shell structures obtained by layer-by-layer deposition. The difference in the microparticle structure was associated with changes in their surface topography and ζ-potential. These microparticles were incubated with human serum or plasma at 37°C for 24 h. The adsorbed proteins were eluted and analyzed by means of SDS-PAGE. The protein composition of the eluates was determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS); a total of 357 proteins were identified, and 183 of them were detected in all samples. Our results demonstrate that the relative abundance of proteins of different functional groups (immunoglobulins, complement proteins, and apolipoproteins) varied depending on the structure and surface characteristics of the polyelectrolyte microparticles and the incubation medium. Our findings expand the understanding of the influence of the physicochemical properties of the microparticles on their interaction with proteins, which can help to improve the design of microparticles for drug delivery.

Recommendations on Monitoring and Replacement of Antithrombin, Fibrinogen, and Von Willebrand Factor in Pediatric Patients on Extracorporeal Membrane Oxygenation: The Pediatric Extracorporeal Membrane Oxygenation Anticoagulation CollaborativE Consensus Conference

OBJECTIVES

To derive systematic review informed, modified Delphi consensus regarding monitoring and replacement of specific coagulation factors during pediatric extracorporeal membrane oxygenation (ECMO) support for the Pediatric ECMO Anticoagulation CollaborativE.

DATA SOURCES

A structured literature search was performed using PubMed, Embase, and Cochrane Library (CENTRAL) databases from January 1988 to May 2020, with an update in May 2021.

STUDY SELECTION

Included studies assessed monitoring and replacement of antithrombin, fibrinogen, and von Willebrand factor in pediatric ECMO support.

DATA EXTRACTION

Two authors reviewed all citations independently, with conflicts resolved by a third reviewer if required. Twenty-nine references were used for data extraction and informed recommendations. Evidence tables were constructed using a standardized data extraction form.

DATA SYNTHESIS

Risk of bias was assessed using the Quality in Prognosis Studies tool. The evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation system. A panel of 48 experts met over 2 years to develop evidence-based recommendations and, when evidence was lacking, expert-based consensus statements. A web-based modified Delphi process was used to build consensus via the Research And Development/University of California Appropriateness Method. Consensus was defined as greater than 80% agreement. We developed one weak recommendation and four expert consensus statements.

CONCLUSIONS

There is insufficient evidence to formulate recommendations on monitoring and replacement of antithrombin, fibrinogen, and von Willebrand factor in pediatric patients on ECMO. Optimal monitoring and parameters for replacement of key hemostasis parameters is largely unknown.

Hemostasis and endothelial functionality: the double face of coagulation factors

Hemostasis is a sophisticated sequence of events aimed at repairing vessel injury. This process occurs in combination with angiogenesis, which leads to new blood vessel formation, helping in wound repair and facilitating tissue healing. The fine mechanisms that regulate hemostasis and angiogenesis are well described, but for a long time, coagulation factors (CF) have been considered merely players in the coagulation cascade. However, evidence from several experiments highlights the crucial functions of these CF in regulating endothelial functionality, especially in the angiogenic process. Some of these CF (e.g., thrombin and tissue factor) have been widely investigated and have been described as triggering intracellular signaling related to endothelial cell (EC) functionality. For others (e.g., factor VIII and thrombomodulin), potential receptors and molecular mechanisms have not been fully elucidated but some data show their potential to induce EC response. This review focuses on the emerging roles of selected CF in regulating EC functions, highlighting in particular their ability to activate signaling pathways involved in angiogenesis, migration, proliferation and endothelial barrier stability.

Characterization of the plasma proteomic profile of Fabry disease: Potential sex- and clinical phenotype-specific biomarkers

Fabry disease (FD) is a X-linked rare lysosomal storage disorder caused by deficient α-galactosidase A (α-GalA) activity. Early diagnosis and the prediction of disease course are complicated by the clinical heterogeneity of FD, as well as by the frequently inconclusive biochemical and genetic test results that do not correlate with clinical course. We sought to identify potential biomarkers of FD to better understand the underlying pathophysiology and clinical phenotypes. We compared the plasma proteomes of 50 FD patients and 50 matched healthy controls using DDA and SWATH-MS. The >30 proteins that were differentially expressed between the 2 groups included proteins implicated in processes such as inflammation, heme and haemoglobin metabolism, oxidative stress, coagulation, complement cascade, glucose and lipid metabolism, and glycocalyx formation. Stratification by sex revealed that certain proteins were differentially expressed in a sex-dependent manner. Apolipoprotein A-IV was upregulated in FD patients with complications, especially those with chronic kidney disease, and apolipoprotein C-III and fetuin-A were identified as possible markers of FD with left ventricular hypertrophy. All these proteins had a greater capacity to identify the presence of complications in FD patients than lyso-GB3, with apolipoprotein A-IV standing out as being more sensitive and effective in differentiating the presence and absence of chronic kidney disease in FD patients than renal markers such as creatinine, glomerular filtration rate and microalbuminuria. Identification of these potential biomarkers can help further our understanding of the pathophysiological processes that underlie the heterogeneous clinical manifestations associated with FD.

CRISPR-Cas9 system: a novel and promising era of genotherapy for beta-hemoglobinopathies, hematological malignancy, and hemophilia

Gene therapy represents a significant potential to revolutionize the field of hematology with applications in correcting genetic mutations, generating cell lines and animal models, and improving the feasibility and efficacy of cancer immunotherapy. Compared to different genetic engineering tools, clustered regularly interspaced short palindromic repeats (CRISPR) CRISPR-associated protein 9 (Cas9) emerged as an effective and versatile genetic editor with the ability to precisely modify the genome. The applications of genetic engineering in various hematological disorders have shown encouraging results. Monogenic hematological disorders can conceivably be corrected with single gene modification. Through the use of CRISPR-CAS9, restoration of functional red blood cells and hemostasis factors were successfully attained in sickle cell anemia, beta-thalassemia, and hemophilia disorders. Our understanding of hemato-oncology has been advanced via CRIPSR-CAS9 technology. CRISPR-CAS9 aided to build a platform of mutated genes responsible for cell survival and proliferation in leukemia. Therapeutic application of CRISPR-CAS9 when combined with chimeric antigen receptor (CAR) T cell therapy in multiple myeloma and acute lymphoblastic leukemia was feasible with attenuation of CAR T cell therapy pitfalls. Our review outlines the latest literature on the utilization of CRISPR-Cas9 in the treatment of beta-hemoglobinopathies and hemophilia disorders. We present the strategies that were employed and the findings of preclinical and clinical trials. Also, the review will discuss gene engineering in the field of hemato-oncology as a proper tool to facilitate and overcome the drawbacks of chimeric antigen receptor T cell therapy (CAR-T).

Mediation effect of antithrombin III between chronic renal insufficiency and chronic coronary artery disease in T2DM patients

PURPOSE

The study aimed to investigate the potential effect of Antithrombin III (ATIII) between chronic renal insufficiency and chronic coronary artery disease (chronic CAD) in type 2 diabetes mellitus (T2DM) patients.

METHODS

T2DM patients hospitalized in ZhongDa Hospital from 2013 to 2018 were enrolled. Relationships between renal function, ATIII, and chronic CAD risk were explored using multivariate regression models. Multiplicative and additive interactions were investigated between ATIII and renal function for CAD risk, and the role of ATIII was determined by bootstrap mediation analysis in patients with chronic renal dysfunction.

RESULTS

A total of 4197 patients were included in the study, with a chronic CAD prevalence of 23.02%. Low ATIII level was statistically associated with chronic renal insufficiency and elevated CAD risk even after adjustments (P < 0.05). A positive correlation between renal function and ATIII was demonstrated, and each 1 SD increase in renal function, ATIII increased by 2.947% (2.406-3.488%, P < 0.001) and 0.969% (0.297-1.642%, P < 0.001) in crude and adjusted models respectively. Patients with decreased renal function and ATIII were at the highest chronic CAD risk (OR = 1.51, 95%CI:1.15-1.98, P < 0.05), while no multiplicative and additive interaction effects were significant. Bootstrap mediation analysis estimated that ATIII mediated approximately 4.27% of the effect of chronic renal insufficiency on chronic CAD risk.

CONCLUSION

ATIII may serve as a mediator between chronic renal insufficiency and chronic CAD, providing mechanistic clues for renal-heart association and new insight into clinical therapies.

Exploring single-molecule interactions: heparin and FGF-1 proteins through solid-state nanopores

Detection and characterization of protein-protein interactions are essential for many cellular processes, such as cell growth, tissue repair, drug delivery, and other physiological functions. In our research, we have utilized emerging solid-state nanopore sensing technology, which is highly sensitive to better understand heparin and fibroblast growth factor 1 (FGF-1) protein interactions at a single-molecule level without any modifications. Understanding the structure and behavior of heparin-FGF-1 complexes at the single-molecule level is very important. An abnormality in their formation can lead to life-threatening conditions like tumor growth, fibrosis, and neurological disorders. Using a controlled dielectric breakdown pore fabrication approach, we have characterized individual heparin and FGF-1 (one of the 22 known FGFs in humans) proteins through the fabrication of 17 ± 1 nm nanopores. Compared to heparin, the positively charged heparin-binding domains of some FGF-1 proteins translocationally react with the pore walls, giving rise to a distinguishable second peak with higher current blockade. Additionally, we have confirmed that the dynamic FGF-1 is stabilized upon binding with heparin-FGF-1 at the single-molecule level. The larger current blockades from the complexes relative to individual heparin and the FGF-1 recorded during the translocation ensure the binding of heparin-FGF-1 proteins, forming binding complexes with higher excluded volumes. Taken together, we demonstrate that solid-state nanopores can be employed to investigate the properties of individual proteins and their complex interactions, potentially paving the way for innovative medical therapies and advancements.

The role of inflammation and antithrombin supplementation on thromboelastographic parameters during veno-venous ECMO for respiratory failure

INTRODUCTION

Extracorporeal membrane oxygenation (ECMO) may act as a driver or propagator of systemic inflammation. In turn, cytokine release can modify thromboelastographic (TEG) tests which are commonly used for anticoagulation monitoring. In this context, antithrombin (AT) supplementation might further modify TEG.

METHODS

This is a pre-specified sub-study of the "Randomized Controlled Trial of Antithrombin Supplementation During Extracorporeal Membrane Oxygenation" study (investigator-initiated, randomized, single-blind, two-arm trial) conducted in two Italian ECMO referral ICUs. Adult patients requiring vv-ECMO for respiratory failure and undergoing unfractioned heparin (UFH) administration were enrolled and randomized whether to receive AT supplementation. Plasma samples for cytokine assay (IL-8, IL-10, IL-6, IL-1β, TNF-α and Pro-ADM) and heparinase TEG were collected from every patient before ECMO start, 24 h and 72 h after ECMO start, before ECMO removal, and 7 days after ECMO removal or upon ICU discharge whichever happened first. AT concentration, coagulation and clinical data were collected before ECMO start and at pre-fixed time points.

RESULTS

Thirty-nine patients were enrolled (21 treatments, 18 controls). TEG-R had a weak-to-moderate positive correlation with IL-8, IL-6, IL-10 and TNF-α and a moderate positive correlation with Pro-ADM. TEG-ANG showed a weak negative correlation with IL-8, IL-6 and TNF-α, while TEG-MA negatively correlated with IL-8, TNF-α and Pro-ADM. AT supplementation seemed to modify the association between TEG-MA and IL-8, IL-10 and Pro-ADM; conversely, AT did not affect the relationship among TEG-R or TEG-ANG and the studied cytokines.

CONCLUSIONS

High concentrations of systemic cytokines correlated with longer reaction times and decreased angle and amplitude at TEG, suggesting that an increase in inflammation is related with hypocoagulability as revealed by thromboelastography.

Clinical and functional characterization of rare compound heterozygous mutations in the SERPINC1 gene causing severe thrombophilia

INTRODUCTION

Hereditary antithrombin (AT) deficiency is a rare autosomal dominant disorder with significant clinical heterogeneity. In the study, we identified a patient with AT deficiency caused by compound heterozygous mutations in the SERPINC1 gene.

METHODS

A total of 9 individuals from three generations were investigated. The mutations were identified by direct sequencing of SERPINC1. Multiple in silico tools were programmed to predict the conservation of mutations and the effect on the AT structure. The coagulation state was evaluated by the thrombin generation assay. Recombinant AT was overexpressed in HEK293T cells; the mRNA level was determined using RT-qPCR. Western blotting, ELISA, and immunocytofluorescence were applied to characterize the recombinant AT protein.

RESULTS

The proband was a 26-year-old male who experienced recurrent venous thrombosis. He presented the type I deficiency with 33 % AT activity and a synchronized decrease in AT antigen. Genetic screening revealed that he carried a heterozygous c.318_319insT (p.Asn107*) in exon 2 and a heterozygous c.922G > T (p.Gly308Cys) in exon 5, both of which were completely conserved in homologous species and resulted in enhanced thrombin generation capability. Hydrophobicity analysis suggested that the p.Gly308Cys mutation may interfere with the hydrophobic state of residues 307-313. In vitro expression studies indicated that the levels of the recombinant protein AT-G308C decreased to 46.98 % ± 2.94 % and 41.35 % ± 1.48 % in transfected cell lysates and media, respectively. After treatment with a proteasome inhibitor (MG132), the quantity of AT-G308C protein in the cytoplasm was replenished to a level comparable to that of the wild type. The mRNA level of AT-N107* was significantly reduced and the recombinant protein AT-N107* was not detected in either the lysate or the culture media.

CONCLUSION

These two mutations were responsible for the AT defects and clinical phenotypes of the proband. The p.Gly308Cys mutation could lead to proteasome-dependent degradation of the AT protein in the cytoplasm by altering local residue hydrophobicity. The c.318_319insT could eliminate aberrant transcripts by triggering nonsense-mediated mRNA degradation. Both mutations resulted in type I AT deficiency.

Coagulation and platelet biology at the intersection of health and disease: illustrated capsules of the 11th Symposium on Hemostasis at the University of North Carolina

The University of North Carolina Symposia on Hemostasis began in 2002, with The First Symposium on Hemostasis with a Special Focus on FVIIa and Tissue Factor. They have occurred biannually since and have maintained the primary goal of establishing a forum for the sharing of outstanding advances made in the basic sciences of hemostasis. The 2024 11th Symposium on Hemostasis will bring together leading scientists from around the globe to present and discuss the latest research related to coagulation factors and platelet biology. In keeping with the tradition of the conference, we expect novel cross-disciplinary collaborations to result from bringing together fundamental scientists and physician-scientists from different backgrounds and perspectives. The aim of these collaborations is to springboard the next generation of important advances in the field. This year's program was designed to discuss Coagulation and Platelet Biology at the Intersection of Health and Disease. The goal is to develop a better understanding of the pathophysiologic mechanisms leading to hemostatic and thrombotic disorders as this understanding is critical for the continued development of safe and efficacious therapeutics. Included in this review article are illustrated capsules provided by our speakers that highlight the main conclusions of the invited talks.

The Inhibition of Serine Proteases by Serpins Is Augmented by Negatively Charged Heparin: A Concise Review of Some Clinically Relevant Interactions

Serine proteases are members of a large family of hydrolytic enzymes in which a particular serine residue in the active site performs an essential role as a nucleophile, which is required for their proteolytic cleavage function. The array of functions performed by serine proteases is vast and includes, among others, the following: (i) the ability to fight infections; (ii) the activation of blood coagulation or blood clot lysis systems; (iii) the activation of digestive enzymes; and (iv) reproduction. Serine protease activity is highly regulated by multiple families of protease inhibitors, known collectively as the SERine Protease INhibitor (SERPIN). The serpins use a conformational change mechanism to inhibit proteases in an irreversible way. The unusual conformational change required for serpin function provides an elegant opportunity for allosteric regulation by the binding of cofactors, of which the most well-studied is heparin. The goal of this review is to discuss some of the clinically relevant serine protease-serpin interactions that may be enhanced by heparin or other negatively charged polysaccharides. The paired serine protease-serpin in the framework of heparin that we review includes the following: thrombin-antithrombin III, plasmin-anti-plasmin, C1 esterase/kallikrein-C1 esterase inhibitor, and furin/TMPRSS2 (serine protease Transmembrane Protease 2)-alpha-1-antitrypsin, with the latter in the context of COVID-19 and prostate cancer.

Persistent complement dysregulation with signs of thromboinflammation in active Long Covid

Long Covid is a debilitating condition of unknown etiology. We performed multimodal proteomics analyses of blood serum from COVID-19 patients followed up to 12 months after confirmed severe acute respiratory syndrome coronavirus 2 infection. Analysis of >6500 proteins in 268 longitudinal samples revealed dysregulated activation of the complement system, an innate immune protection and homeostasis mechanism, in individuals experiencing Long Covid. Thus, active Long Covid was characterized by terminal complement system dysregulation and ongoing activation of the alternative and classical complement pathways, the latter associated with increased antibody titers against several herpesviruses possibly stimulating this pathway. Moreover, markers of hemolysis, tissue injury, platelet activation, and monocyte-platelet aggregates were increased in Long Covid. Machine learning confirmed complement and thromboinflammatory proteins as top biomarkers, warranting diagnostic and therapeutic interrogation of these systems.

Regulation of the innate immune system by fragmented heparin-conjugated lipids on lipid bilayered membranes in vitro

Surface modification with heparin is a powerful biomaterial coating strategy that protects against innate immunity activation since heparin is a part of the proteoglycan heparan sulfate on cell surfaces in the body. We studied the heparinization of cellular and material surfaces via lipid conjugation to a heparin-binding peptide. In the present study, we synthesized fragmented heparin (fHep)-conjugated phospholipids and studied their regulation of the innate immune system on a lipid bilayered surface using liposomes. Liposomes have versatile applications, such as drug-delivery systems, due to their ability to carry a wide range of molecules. Owing to their morphological similarity to cell membranes, they can also be used to mimic a simple cell-membrane to study protein-lipid interactions. We investigated the interaction of complement-regulators, factor H and C4b-binding protein (C4BP), as well as the coagulation inhibitor antithrombin (AT), with fHep-lipids on the liposomal surface. Herein, we studied the ability of fHep-lipids to recruit factor H, C4BP, and AT using a quartz crystal microbalance with dissipation monitoring. With dynamic light scattering, we demonstrated that liposomes could be modified with fHep-lipids and were stable up to 60 days at 4 °C. Using a capillary western blot-based method (Wes), we showed that fHep-liposomes could recruit factor H in a model system using purified proteins and assist in the degradation of the active complement protein C3b to iC3b. Furthermore, we found that fHep-liposomes could recruit factor H and AT from human plasma. Therefore, the use of fHep-lipids could be a potential coating for liposomes and cell surfaces to regulate the immune system on the lipid surface.

Complement and coagulation crosstalk - Factor H in the spotlight

The immune complement and the coagulation systems are blood-based proteolytic cascades that are activated by pathway-specific triggers, based on protein-protein interactions and enzymatic cleavage reactions. Activation of these systems is finely balanced and controlled through specific regulatory mechanisms. The complement and coagulation systems are generally viewed as distinct, but have common evolutionary origins, and several interactions between these homologous systems have been reported. This complement and coagulation crosstalk can affect activation, amplification and regulatory functions in both systems. In this review, we summarize the literature on coagulation factors contributing to complement alternative pathway activation and regulation and highlight molecular interactions of the complement alternative pathway regulator factor H with several coagulation factors. We propose a mechanism where factor H interactions with coagulation factors may contribute to both complement and coagulation activation and regulation within the haemostatic system and fibrin clot microenvironment and introduce the emerging role of factor H as a modulator of coagulation. Finally, we discuss the potential impact of these protein interactions in diseases associated with factor H dysregulation or deficiency as well as evidence of coagulation dysfunction.

Identification of thrombin inhibiting antithrombin-III like protein from Punica granatum using in silico approach and in vitro validation of thrombin inhibition activity in crude protein

Thrombosis is characterized by the formation of clots in the blood vessels. Antithrombin-III deficiency in the blood causes thrombus formation. Supplementing antithrombin-III may serve as anticoagulant therapy. In the present studies, an antithrombin like Protein from Punica granatum has been identified and characterized using in silico approach. Based on sequence homology, an ALPP was selected depending upon its highest binding affinity of -41.28 kcal/mol with thrombin. Thrombin structure complexed with ALPP was docked with TAME using AutoDock Vina. No binding was observed for TAME at Ser195 of thrombin. MD simulation (50 ns) was performed to evaluate the flexibility and stability of docked complexes. In vitro assays with crude protein showed 78% thrombin inhibition at 5 µg and calculated IC50 value was 0.188 µg. The presence of thrombin inhibitors in crude protein was also confirmed by reverse zymography. Thus, it is very likely that the protein identified from P. granatum may act as thrombin inhibitor.