Analysis of coagulation factors in angioedema/urticaria: increased values of D-dimer and fibrinogen in isolated angioedema.

INTRODUCTION: Recent research has shown that blood coagulation and the extrinsic coagulation cascade are involved in the pathogenesis of chronic spontaneous urticaria (CSU), but little is known about the coagulation factors in angioedema. METHODS: This study included 58 participants: 29 patients with chronic angioedema (14 with isolated angioedema and 15 with angioedema with wheals) and 29 healthy controls (HCs). We compared the values of coagulation factors in patients with isolated angioedema to those with wheals. Plasma levels of D-dimer, fibrinogen, and factor VII were measured by enzyme-linked immunosorbent assay (ELISA) for all participants. RESULTS: Significantly higher D-dimer (p = 0.016; ε² = 0.381) and fibrinogen (p = 0.044; ε² = 0.331) levels were recorded in patients with angioedema (both groups) than in the HCs, with higher levels for angioedema with wheals. Factor VII and fibrinogen levels did not differ significantly between the groups with angioedema, but coagulation factors were more often elevated in both angioedema groups than in HCs. CONCLUSIONS: One characteristic of angioedema is an elevated blood coagulation potential, which may help produce fibrin and may be important in controlling angioedema attacks.

Post-Translational Oxidative Modifications of Hemostasis Proteins: Structure, Function, and Regulation.

Reactive oxygen species (ROS) are constantly generated in a living organism. An imbalance between the amount of generated reactive species in the body and their destruction leads to the development of oxidative stress. Proteins are extremely vulnerable targets for ROS molecules, which can cause oxidative modifications of amino acid residues, thus altering structure and function of intra- and extracellular proteins. The current review considers the effect of oxidation on the structural rearrangements and functional activity of hemostasis proteins: coagulation system proteins such as fibrinogen, prothrombin/thrombin, factor VII/VIIa; anticoagulant proteins - thrombomodulin and protein C; proteins of the fibrinolytic system such as plasminogen, tissue plasminogen activator and plasminogen activator inhibitor-1. Structure and function of the proteins, oxidative modifications, and their detrimental consequences resulting from the induced oxidation or oxidative stress in vivo are described. Possible effects of oxidative modifications of proteins in vitro and in vivo leading to disruption of the coagulation and fibrinolysis processes are summarized and systematized, and the possibility of a compensatory mechanism in maintaining hemostasis under oxidative stress is analyzed.

Human platelet concentrates treated with microbicidal 405 nm light retain hemostasis activity.

Chemical and UV light-based pathogen reduction technologies are currently in use for human platelet concentrates (PCs) to enhance safety from transfusion-transmitted infections. Relative to UV light, 405 nm violet-blue light in the visible spectrum is known to be less harmful. Hence, in this report for the first time, we have assessed the global hemostasis activity of PCs stored in plasma and the activities of six plasma coagulation factors (CFs) as a measure of in vitro hemostatic activity following exposure to the microbicidal 405 nm light. Apheresis PC samples collected from each screened human donor (n = 22) were used for testing of PCs and platelet poor plasma (PPP). Both PCs and PPPs were treated for 5 h with 405 nm light to achieve a previously established microbicidal light dose of 270 J/cm2. Activated partial thromboplastin time and prothrombin time-based potency assays using a coagulation analyzer and hemostatic capacity via Thromboelastography were analyzed. Thromboelastography analysis of the light-treated PCs and plasma present in the PCs showed little difference between the treated and untreated samples. Further, plasma present in the PCs during the light treatment demonstrated a better stability in potency assays for several coagulation factors compared to the plasma alone prepared from PCs first and subjected to the light treatment separately. Overall, PCs stored in plasma treated with 405 nm violet-blue light retain activity for hemostasis.

Emicizumab promotes factor Xa generation on endothelial cells.

BACKGROUND: Until recently, the treatment of hemophilia A relied on factor (F)VIII replacement. However, up to one-third of patients with severe hemophilia A develop neutralizing alloantibodies that render replacement therapies ineffective. The development of emicizumab, a bispecific antibody that partially mimics FVIIIa, has revolutionized the treatment of these patients. However, the use of an activated prothrombin complex concentrate [FEIBA (Takeda)] to treat breakthrough bleeding in patients on emicizumab has been associated with thrombotic complications including a unique microangiopathy. OBJECTIVES: We hypothesized that the thrombotic complications observed with the combination of emicizumab and FEIBA might be due to excessive expression of procoagulant activity on the surface of endothelial cells. METHODS: We examined the ability of emicizumab to promote FX activation on endothelial cells using 2 cell culture models. RESULTS: We found that endothelial cells readily support emicizumab-mediated activation of FX by FIXa. The level of FXa generation depends on the concentration of available FIXa. The addition of FEIBA to emicizumab increased FXa generation in a dose-dependent manner on endothelial cells in both models. The rate of FXa generation was further enhanced by endothelial cell activation. However, unlike emicizumab, we found limited FXa generation in the presence of FVIII(a), which followed a significant lag time and was not dependent on FIXa concentration under these conditions. CONCLUSION: Emicizumab promotes FXa generation on the surface of endothelial cells, which is markedly enhanced in the presence of FEIBA. These findings demonstrate a potential mechanism for the thrombotic complications seen with the combined use of emicizumab and FEIBA.

Mathematical models of coagulation-are we there yet?

BACKGROUND: Mathematical models of coagulation have been developed to mirror thrombin generation in plasma, with the aim of investigating how variation in coagulation factor levels regulates hemostasis. However, current models vary in the reactions they capture and the reaction rates used, and their validation is restricted by a lack of large coherent datasets, resulting in questioning of their utility. OBJECTIVES: To address this debate, we systematically assessed current models against a large dataset, using plasma coagulation factor levels from 348 individuals with normal hemostasis to identify the causes of these variations. METHODS: We compared model predictions with measured thrombin generation, quantifying and comparing the ability of each model to predict thrombin generation, the contributions of the individual reactions, and their dependence on reaction rates. RESULTS: We found that no current model predicted the hemostatic response across the whole cohort and all produced thrombin generation curves that did not resemble those obtained experimentally. Our analysis has identified the key reactions that lead to differential model predictions, where experimental uncertainty leads to variability in predictions, and we determined reactions that have a high influence on measured thrombin generation, such as the contribution of factor XI. CONCLUSION: This systematic assessment of models of coagulation, using large dataset inputs, points to ways in which these models can be improved. A model that accurately reflects the effects of the multiple subtle variations in an individual's hemostatic profile could be used for assessing antithrombotics or as a tool for precision medicine.

TGFß macrophage reprogramming: a new dimension of macrophage plasticity.

The August 2023 article in Science Signaling, "TGF-ß uncouples glycolysis and inflammation in macrophages and controls survival during sepsis," challenges the traditional M1/M2 macrophage classification by investigating the impact of transforming growth factor ß on macrophage metabolism and function. Despite its conventional anti-inflammatory role, transforming growth factor ß-treated macrophages exhibit a distinct phenotype marked by heightened glycolysis, suppressed proinflammatory cytokines, and increased coagulation factor expression. The study identifies phosphofructokinase, liver type as a crucial glycolytic enzyme regulated by transforming growth factor ß via the mTOR-c-MYC pathway. Epigenetic changes induced by transforming growth factor ß, such as increased Smad3 activation and reduced proinflammatory transcription factor motif enrichment, contribute to the anti-inflammatory profile. The research extends its implications to sepsis, revealing the role of transforming growth factor ß in exacerbating coagulation and reducing survival in mouse models. This effect involves upregulation of coagulation factor F13A1, dependent on phosphofructokinase, liver type activity and glycolysis in macrophages. Connections to COVID-19 pathology are drawn, as transforming growth factor ß-treated macrophages and SARS-CoV-2 E protein-exposed cells display similar metabolic profiles. Bioinformatic analysis of COVID-19 patient data suggests correlations between myeloid expression of TGFßR1, PFKL, and F13A1 with disease severity. The study challenges the M1/M2 classification, emphasizing the complexity of macrophage responses influenced by transforming growth factor ß, proposing transforming growth factor ß as a potential therapeutic target for conditions like sepsis and COVID-19 where dysregulated coagulation is significant. Overall, the research provides valuable insights into transforming growth factor ß-mediated immunometabolic regulation, paving the way for future investigations and potential therapeutic interventions.

Coagulation management during liver transplantation: monitoring and decision making for hemostatic interventions.

PURPOSE OF REVIEW: Rebalanced hemostasis describes the precarious balance of procoagulant and antithrombotic proteins in patients with severe liver failure. This review is aimed to discuss currently available coagulation monitoring tests and pertinent decision-making process for plasma coagulation factor replacements during liver transplantation (LT). RECENT FINDINGS: Contemporary viscoelastic coagulation monitoring systems have demonstrated advantages over conventional coagulation tests in assessing the patient's coagulation status and tailoring hemostatic interventions. There is increasing interest in the use of prothrombin complex and fibrinogen concentrates, but it remains to be proven if purified factor concentrates are more efficacious and safer than allogeneic hemostatic components. Furthermore, the decision to use antifibrinolytic therapy necessitates careful considerations given the risks of venous thromboembolism in severe liver failure. SUMMARY: Perioperative hemostatic management and thromboprophylaxis for LT patients is likely to be more precise and patient-specific through a better understanding and monitoring of rebalanced coagulation. Further research is needed to refine the application of these tools and develop more standardized protocols for coagulation management in LT.

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.

Self-anticoagulant sponge for whole blood auto-transfusion and its mechanism of coagulation factor inactivation.

Clinical use of intraoperative auto-transfusion requires the removal of platelets and plasma proteins due to pump-based suction and water-soluble anticoagulant administration, which causes dilutional coagulopathy. Herein, we develop a carboxylated and sulfonated heparin-mimetic polymer-modified sponge with spontaneous blood adsorption and instantaneous anticoagulation. We find that intrinsic coagulation factors, especially XI, are inactivated by adsorption to the sponge surface, while inactivation of thrombin in the sponge-treated plasma effectively inhibits the common coagulation pathway. We show whole blood auto-transfusion in trauma-induced hemorrhage, benefiting from the multiple inhibitory effects of the sponge on coagulation enzymes and calcium depletion. We demonstrate that the transfusion of collected blood favors faster recovery of hemostasis compared to traditional heparinized blood in a rabbit model. Our work not only develops a safe and convenient approach for whole blood auto-transfusion, but also provides the mechanism of action of self-anticoagulant heparin-mimetic polymer-modified surfaces.

The international normalised ratio to monitor coagulation factor production during normothermic machine perfusion of human donor livers.

BACKGROUND: Normothermic machine perfusion (NMP) of donor livers allows for new diagnostic and therapeutic strategies. As the liver produces most of the haemostatic proteins, coagulation assays such as the International Normalised Ratio (INR) performed in perfusate may be useful to assess hepatocellular function of donor livers undergoing NMP. However, high concentrations of heparin and low levels of fibrinogen may affect coagulation assays. METHODS: Thirty donor livers that underwent NMP were retrospectively included in this study, of which 18 were subsequently transplanted. We measured INRs in perfusate in presence or absence of exogenously added fibrinogen and/or polybrene. Additionally, we prospectively included 14 donor livers that underwent NMP (of which 11 were transplanted) and measured INR using both a laboratory coagulation analyser and a point-of-care device. RESULTS: In untreated perfusate samples, the INR was above the detection limit in all donor livers. Addition of both fibrinogen and polybrene was required for adequate INR assessment. INRs decreased over time and detectable perfusate INR values were found in 17/18 donor livers at the end of NMP. INR results were similar between the coagulation analyser and the point-of-care device, but did not correlate with established hepatocellular viability criteria. CONCLUSIONS: Most of the donor livers that were transplanted showed a detectable perfusate INR at the end of NMP, but samples require processing to allow for INR measurements using laboratory coagulation analysers. Point-of-care devices bypass this need for processing. The INR does not correlate with established viability criteria and might therefore have additional predictive value.

Quantification of proteomic profile changes in the hemolymph of crayfish during in vitro coagulation.

Hemolymph is the circulatory fluid that fills the body cavity of crustaceans, analogous to blood in vertebrates. Hemolymph coagulation, similar to blood clotting in vertebrates, plays a crucial role in wound healing and innate immune responses. Despite extensive studies on the clotting process in crustaceans, no comparative quantitative analysis of the protein composition of non-clotted and clotted hemolymph in any decapod has been reported. In this study, we used label-free protein quantification with high-resolution mass spectrometry to identify the proteomic profile of hemolymph in crayfish and quantify significant changes in protein abundances between non-clotted and clotted hemolymph. Our analysis identified a total of two-hundred and nineteen proteins in both hemolymph groups. Furthermore, we discussed the potential functions of the top most high and low-abundant proteins in hemolymph proteomic profile. The quantity of most of the proteins was not significantly changed during coagulation between non-clotted and clotted hemolymph, which may indicate that clotting proteins are likely pre-synthesized, allowing for a swift coagulation response to injury. Four proteins still showed abundance differences (p < 0.05, fold change>2), including C-type lectin domain-containing proteins, Laminin A chain, Tropomyosin, and Reverse transcriptase domain-containing proteins. While the first three proteins were down-regulated, the last one was up-regulated. The down-regulation of structural and cytoskeletal proteins may affect the process of hemocyte degranulation needed for coagulation, while the up-regulation of an immune-related protein might be attributed to the phagocytosis ability of viable hemocytes during coagulation.

Deficiency of coagulation factors is associated with the bleeding diathesis of severe yellow fever.

Yellow fever (YF) is an acute tropical infectious disease caused by an arbovirus and can manifest as a classic hemorrhagic fever. The mechanism of the bleeding diathesis in YF is not well understood. We assessed clinical and laboratory data (including a panel of coagulation tests) from 46 patients with moderate (M) and severe (S) YF admitted to a local hospital between January 2018 and April 2018. Among 46 patients, 34 had SYF of whom 12 (35%) patients died. A total of 21 (45%) patients developed some type of bleeding manifestation and 15 (32%) presented severe bleeding. Patients with SYF had more severe thrombocytopenia (p = 0.001); prolonged activated partial thromboplastin time (aPTT) and thrombin time (TT) (p = 0.03 and p = 0.005, respectively); reduced plasma levels of coagulation factor (F) II (p < 0.01), FIX (p = 0.01), and FX (p = 0.04); and D-dimer levels almost 10 times higher (p < 0.01) when compared with patients with MYF. Patients who died had more bleeding (p = 0.03), more major bleeding (p = 0.03), prolonged international normalized ratio (INR) and aPTT (p = 0.003 and p = 0.002, respectively), as well as lower activity of FII (p = 0.02), FV (p = 0.001), FVII (p = 0.005), FIX (p = 0.01), and protein C (p = 0.01) than the ones who survived. FVIII levels were either normal or increased in all patients studied. Our results suggest that the bleeding diathesis of SYF is associated with the deficiency of coagulation factors produced by the liver. Prolonged INR and aPTT and reduced FII, FV, FVII, FIX, and protein C were associated with death.

Status of major hemostatic components in the setting of COVID-19: the effect on endothelium, platelets, coagulation factors, fibrinolytic system, and complement.

The coagulation, fibrinolytic, anticoagulation, and complement systems are in delicate balance with the vessel wall endothelium ensuring appropriate hemostasis. Coagulopathy in coronavirus disease 2019 (COVID-19) is not a simple disorder of one hemostatic component but a complicated process affecting most of the hemostasis system. COVID-19 disturbs the balance between the procoagulant systems and the regulatory mechanisms. Here, we investigate the effect of COVID-19 on key hemostatic components, including platelets, endothelial cells, coagulation factors, fibrinolytic system, anticoagulant protein system, and complement system, to improve our understanding of the pathophysiological processes underlying COVID-19 coagulopathy based on evidence.

Potential utility of a multi-component coagulation factor panel to calculate MELD scores and assess the risk of portal vein thrombosis in chronic liver disease.

BACKGROUND: Current quantitative approaches to assess chronic liver disease (CLD) severity have limitations. Further, portal vein thrombosis (PVT) pre-liver transplant (LT) is a major contributor to morbidity in CLD; the means of detecting and/or predicting PVT are limited. We sought to explore whether plasma coagulation factor activity levels can serve as a substitute for prothrombin time/international normalized ratio (PT/INR) in the Model for End-stage Liver Disease (MELD), and/or help assess the risk of PVT. METHODS: Plasma activity levels of Factor V (FV), Factor VIII (FVIII), Protein C (PC), and Protein S (PS) and the concentrations of D-dimer, sP-selectin, and asTF were assessed in two cohorts of CLD patients (ambulatory, n = 42; LT, n = 43). RESULTS: FV and PC activity levels strongly correlated with MELD scores, which enabled the development of a novel scoring system based on multiple linear regressions of the correlations of FV and PC activity with MELD-Na that substitutes PT/INR. Six-month and 1-year follow-up revealed that our novel approach was non-inferior to MELD-Na at predicting mortality. A significant inverse correlation between FVIII activity levels and PVT was found in the LT cohort (p = 0.010); FV and PS activity levels were in-trend (p = 0.069, p = 0.064). We developed a logistic regression-based compensation score to identify patients at risk of PVT. CONCLUSIONS: We demonstrate that FV and PC activity levels may be used to replace PT/INR in MELD scoring. We also show the potential of using the combination of FV, FVIII, and PS activity levels to assess the risk of PVT in CLD.

Blood coagulation factors and platelet response to drug-induced hepatitis and hepatosis in rats.

BACKGROUND: Knowing the variability of blood coagulation responses to liver damage of different origins can provide a key to curing liver tissues or to mitigating treatment side effects. The aim of the present work was to compare the changes in the main components of hemostasis under experimental drug-induced hepatosis and hepatitis in rats. METHODS: We modeled diclofenac-induced hepatitis and tetracycline-induced hepatosis. Hemostasis response was gauged by measuring fibrinogen, factor X, protein C (PC), and prothrombin in plasma. The decarboxylated form of prothrombin was detected by measuring prothrombin index and ecamulin index. Platelet reactivity was studied using aggregometry. RESULTS: Both hepatitis and hepatosis decreased the synthesis of fibrinogen, factor X, and prothrombin. However, protein carboxylation was not disrupted in hepatosis but was much impaired in hepatitis. PC decreased in both models as a consequence of its consumption possibly during inflammatory response. Platelet aggregation rate was lower in hepatosis but higher in hepatitis. CONCLUSIONS: Our findings imply the need for a thorough monitoring of the hemostasis system in liver diseases to avoid possible thrombotic complications. Its state indicates the disorder's rate and character.

Composition of plasma in apheresis-derived platelet concentrates under cold storage.

BACKGROUND: Compared to room temperature (RT, 22-24°C) storage, refrigeration of platelet concentrates (PC) may provide advantages due to lower risks of bacterial growth and increased responsiveness of platelets. However, storage at cold temperature (CT, 2-6°C) may also strongly influence the plasmatic composition of PC. This study analysed the content of plasma in apheresis-derived platelet concentrates (APC). MATERIALS AND METHODS: APC were stored under blood bank conditions at CT or RT. On days 0 and 6, samples were drawn for analysis. Coagulation parameters comprised global coagulation assays, single factors or inhibitors. The distribution pattern of von Willebrand multimers was investigated by immunoblotting. Thrombin generation was assessed with a fluorescence assay. Immunological and clinical chemistry parameters were determined on automated analysers. RESULTS: After storage at CT, coagulation factors V, VII, IX or protein S activity are partially reduced, but less compromised than under RT. There was a large reduction in Factor VIII levels and this was similar at both temperatures. In contrast to RT, von Willebrand Factor (vWF) activity was remarkably decreased at CT, and this was accompanied by the shift from high molecular to low molecular weight multimers. Thrombin generation showed improved preservation at CT. Other plasma proteins like immunoglobulins were stable at both conditions. DISCUSSION: Refrigeration mediates a bivalent effect on plasmatic coagulation in APC. At CT, the partial reduction of labile coagulation factors is less emphasised. However, CT does not prevent Factor VIII depletion, but induces an additional loss of vWF activity by multimer cleavage. Preserved thrombin generation may indicate a higher hemostatic capacity for cold storage.

Sex-specific associations between serum lipids and hemostatic factors: the cross-sectional population-based KORA-fit study.

BACKGROUND: Studies on the associations between lipid parameters and different hemostatic factors in men and women from the general population are scarce. It was therefore examined whether there are possible relationships between routinely measured serum lipids (total cholesterol, HDL-cholesterol, non-HDL-cholesterol, LDL-cholesterol, and triglycerides) and different hemostatic factors (activated partial thromboplastin time (aPTT), fibrinogen, factor VIII, antithrombin III (AT III), protein C, protein S, and D-dimer). METHODS: The analysis was based on data from the Cooperative Health Research in the Region of Augsburg (KORA)-Fit study, which included 805 participants (378 men, 427 women) with a mean age of 63.1 years. Sex-specific associations between serum lipids and coagulation factors were investigated using multivariable linear regression models. RESULTS: In men, total cholesterol was inversely related to aPTT but positively associated with protein C activity. HDL cholesterol was inversely related to aPTT and fibrinogen. LDL cholesterol, non-HDL cholesterol, and triglycerides showed a positive association with protein C and protein S activity. In women, LDL-cholesterol, total cholesterol, and non-HDL-cholesterol were positively related to AT III concentrations and protein C and S activity. Additionally, non-HDL-cholesterol was positively associated with factor VIII activity. HDL cholesterol was inversely related to fibrinogen. Triglycerides showed a positive relationship with protein C activity. CONCLUSIONS: There seem to be sex differences regarding various associations between blood lipid levels and hemostatic factors. Further studies are needed to address the possible impact of these associations on cardiovascular risk and the underlying mechanisms.

Domain Evolution of Vertebrate Blood Coagulation Cascade Proteins.

Vertebrate blood coagulation is controlled by a cascade containing more than 20 proteins. The cascade proteins are found in the blood in their zymogen forms and when the cascade is triggered by tissue damage, zymogens are activated and in turn activate their downstream proteins by serine protease activity. In this study, we examined proteomes of 21 chordates, of which 18 are vertebrates, to reveal the modular evolution of the blood coagulation cascade. Additionally, two Arthropoda species were used to compare domain arrangements of the proteins belonging to the hemolymph clotting and the blood coagulation cascades. Within the vertebrate coagulation protein set, almost half of the studied proteins are shared with jawless vertebrates. Domain similarity analyses revealed that there are multiple possible evolutionary trajectories for each coagulation protein. During the evolution of higher vertebrate clades, gene and genome duplications led to the formation of other coagulation cascade proteins.

Delivery of Cas9-guided ABE8e into stem cells using poly(l-lysine) polypeptides for correction of the hemophilia-associated FIX missense mutation.

The coagulation factor 9 gene (FIX) point mutation contributes to most hemophilia B cases, providing ideal gene correction models. Here we identified the frequent mutation G20519A (R226Q) in FIX, which resulted in many severe and moderate hemophilia B patients. This study aimed to investigate the effect of HDR and base editing in correcting FIX mutant. We first constructed HEK293 and liver-derived cell lines Huh7 cells stabling carrying mutated FIX containing G20519A (HEK293-FIXmut and Huh7-FIXmut). Then, CRISPR/Cas9-based homology-directed repair (HDR) and base editing were used for the correction of this mutated point. We used Cas9 nickase (nCas9) mediated HDR and the advanced base editor ABE8e to correct G20519A and then measured the concentration and activity of FIX. Furthermore, we used the star-shaped poly(lysine) gene nanocarriers to deliver the ABE8e correction systems into HEK293-FIXmut and Huh7-FIXmut stem cells to correct mutated FIX. As a result, we found that gRNAs directed inefficient HDR in correcting G20519A. The ABE8e corrected the mutation efficiently in both HEK293-FIXmut and Huh7-FIXmut stem cells. In addition, the star-shaped poly(lysine) carriers delivered non-viral vectors into stem cells efficiently. The nanocarriers-delivered ABE8e system corrected mutated FIX in stem cells, and the stem cells secreted active FIX in high concentration. In conclusion, our study provides a potential alternative for correcting mutated FIX in hemophilia B patients.

Salvianolic acid A alleviates lipopolysaccharide-induced disseminated intravascular coagulation by inhibiting complement activation.

INTRODUCTION: Disseminated intravascular coagulation (DIC) is a syndrome characterized by coagulopathy, microthrombus, and multiple organ failure. The complement system in DIC is overactivated, and the functions of complement and coagulation pathways are closely related. Our previous screening revealed that salvianolic acid A (SAA) has anti-complement activity. The hyper-activated complement system was involved in the lipopolysaccharide (LPS) induced DIC in rats. The effects of SAA anti-complement action on LPS-induced DIC in rats were investigated. METHODS: The complement activity of the classical pathway and alternative pathway was detected through an in vitro hemolysis assay. The binding sites of SAA and complement C3b were predicted by molecular docking. LPS-induced disseminated coagulation experiments were performed on male Wistar rats to assess coagulation function, complement activity, inflammation, biochemistry, blood routine, fibrinolysis, and survival. RESULTS: SAA had an anti-complement activity in vivo and in vitro and inhibited the complement activation in the classical and alternative pathway of complement. The infusion of LPS into the rats impaired the coagulation function, increased the plasma inflammatory cytokine level, complemented activation, reduced the clotting factor levels, fibrinogen, and platelets, damaged renal, liver, and lung functions, and led to a high mortality rate (85%). SAA treatment of rats inhibited complement activation and attenuated the significant increase in D-dimer, interleukin-6, alanine aminotransferase, and creatinine. It ameliorated the decrease in plasma levels of fibrinogen and platelets and reversed the decline in activity of protein C and antithrombin III. The treatment reduced kidney, liver, and lung damage, and significantly improved the survival rate of rats (46.2 and 78.6% for the low- and high-dose groups, respectively). CONCLUSION: SAA reduced LPS-induced DIC by inhibiting complement activation. It has considerable potential in DIC treatment.