Antibodies to tissue-type plasminogen activator (t-PA) in patients with inflammatory bowel disease: high prevalence, interactions with functional domains of t-PA and possible implications in thrombosis

Inflammatory Bowel Disease: An Indication to Screen for Thrombophilia?

Inflammatory bowel diseases (IBD) are systemic conditions characterized by multiple intestinal and extra-intestinal manifestations related to the associated chronic inflammatory state. Among their diverse extra-intestinal complications, venous thromboembolism (VTE) remains one of the most under recognized causes of morbidity and mortality in these patients, highlighting the need for a better understanding of the underlying mechanism of hypercoagulability, in addition to the role of acquired and inherited risk factors that further increase the risk of thrombosis with its impact on patients’ outcomes. We hereby present a review of the data regarding thrombosis in the setting of IBD, elucidating the possible role for screening in this high-risk category of patients and specifically in areas where inherited thrombophilia is expected to be highly prevalent, reporting two patients with IBD, one who developed a cerebrovascular event and another one who had recurrent VTE events; nevertheless, both of them had inherited thrombophilic mutations. The identification of specific genetic abnormalities in those patients reintroduces the controversy related to the need to screen a specific category of patients with IBD for hereditary thrombophilia, especially in regions characterized by a higher prevalence of such thrombophilic alterations.

Homocysteine is potential serological marker for predicting the risk of deep venous thrombosis of the lower extremities in patients received operation of lower limb fracture

Objective

The aim of the study is to investigate the correlations among serum homocysteine (Hcy), D-dimer, and the risk of developing deep venous thrombosis (DVT) of the lower extremities in patients who underwent operation for lower limb fracture.

Methods

Seventy-five cases who underwent operation for lower limb fracture were included and further divided into DVT group (n = 26) and control group (n = 49) based on post-DVT diagnostic criteria. The serum Hcy and D-dimer were examined 48 h after operation. The serum Hcy and D-dimer levels were compared between the two groups. The correlation between serum Hcy and D-dimer was investigated by the Pearson correlation test. The receiver-operating characteristic (ROC) curve was applied to evaluate the diagnostic performance of serum Hcy and D-dimer as serological markers for DVT.

Results

The serum Hcy concentrations were 11.96 ± 3.98 μmol/L and 7.92 ± 3.27 μmol/L for DVT and control groups, respectively, with statistical difference (t = 4.72, P < 0.01). The serum D-dimer in the DVT group was significantly higher than that of the control group (8.99 ± 4.50 vs 1.70 ± 2.11) μg/mL with statistical difference (t = 9.56, P < 0.01). Line regression analysis indicated that serum Hcy was positively correlated with serum D-dimer concentration and can be demonstrated by the equation of Y = 0.6651*X + 1.036 for the DVT group. Using serum Hcy as the biomarker for predicting DVT, the prediction sensitivity and specificity were 76.92 and 71.44%, respectively, with the AUC of 0.7804 under the cut-point of 9.54 μmol/L. For serum D-dimer, the prediction sensitivity and specificity were 96.15 and 73.47%, respectively, with the area under the ROC (AUC) of 0.9455 under the cut-point of 1.66 μg/mL.

Conclusion

Serum Hcy was significantly elevated in DTV patients, and hence, it can be applied as a serological marker for DVT prediction in patients who underwent operation for lower limb fracture. However, the DVT prediction performance of serum Hcy was inferior to D-dimer especially for diagnostic sensitivity.

Coagulation status, fibrinolysis, and platelet dynamics in dogs with chronic inflammatory enteropathy

Background

Coagulation status is poorly understood in dogs with chronic inflammatory enteropathy (CIE). Fibrinolytic activity and platelet dynamics have not been evaluated in CIE dogs.

Objectives

To assess coagulation status and fibrinolysis in normoalbuminemic CIE dogs (CIE‐N) and CIE dogs with protein‐losing enteropathy (CIE‐PLE) compared to healthy controls (HC). To evaluate thromboelastography (TEG) variable differences between groups and for correlations with clinicopathologic data. To report platelet dynamics in CIE dogs.

Animals

Twenty‐five client‐owned dogs with CIE (n = 16 CIE‐N; n = 9 CIE‐PLE); 14 HC beagle dogs.

Methods

All dogs had tissue factor + tissue plasminogen activator TEG. Nine of 25 CIE dogs had whole blood impedance platelet aggregometry. The TEG variables and coagulation data were compared between all CIE vs HC dogs, CIE‐N dogs vs HC, and CIE‐PLE dogs vs HC. Clinicopathologic and coagulation data were available for CIE dogs and assessed for correlation to TEG variables.

Results

Dogs with CIE had higher maximum amplitude (MA; P < .001), longer clot lysis times (CLTs; P < .001), lower % lysis after 30 minutes (LY30; P < .001), and % lysis after 60 minutes (LY60; P < .001) compared to HC, suggesting hypercoagulability and hypofibrinolysis. When separated out, both CIE‐N and CIE‐PLE dogs had higher MA, longer CLT, and lower LY30 and LY60 compared to HC. Serum albumin and 25‐hydroxyvitamin D (25[OH]D) concentrations, and plasma antithrombin and fibrinogen concentrations moderately correlated with MA.

Conclusions and Clinical Importance

Normoalbuminemic and hypoalbuminemic CIE dogs were considered hypercoagulable based on TEG compared to HC. Some CIE dogs displayed hypofibrinolytic phenotypes on TEG.

Experimental and Clinical Evidence of Endothelial Dysfunction in Inflammatory Bowel Disease

The endothelium has a crucial role in proper hemodynamics. Inflammatory bowel disease (IBD) is mainly a chronic inflammatory condition of the gastrointestinal tract. However, considerable evidence points to high cardiovascular risk in patients with IBD. This review positions the basic mechanisms of endothelial dysfunction in the IBD setting (both clinical and experimental). Furthermore, we review the main effects of drugs used to treat IBD in endothelial (dys)function. Moreover, we leave challenging points for enlarging the therapeutic arsenal for IBD with new or repurposed drugs that target endothelial dysfunction besides inflammation.

Coagulation and Skin Autoimmunity

Several lines of evidence indicate that the immune system, inflammation, and coagulation are simultaneously activated in autoimmune and immune-mediated skin diseases. Pro-inflammatory cytokines such as interleukin-6 and tumor necrosis factor-alpha induce the expression of the main initiator of coagulation, i.e., tissue factor. The proteases of coagulation in turn act on protease-activated receptors inducing the expression of various pro-inflammatory cytokines triggering inflammation. The cross-talk among immune system, inflammation, and coagulation amplifies and maintains the activation of all three pathways. This review focuses on three skin disorders as chronic spontaneous urticaria (CSU), angioedema, and bullous pemphigoid (BP), in which the relationships among the three systems have been investigated or their clinical consequences are relevant. Markers of thrombin generation, fibrinolysis, and inflammation have been reported to be increased in the plasma during flares of CSU and angioedema, as well as in the active phase of BP, with the marker levels reverting to normal during remission. The coagulation activation seems to be important only at local level in CSU and angioedema while both at local and systemic levels in BP which is the only condition associated with an increased thrombotic risk. The prothrombotic state in autoimmune skin diseases raises the question of the indication of anticoagulant treatment, particularly in the presence of other cardiovascular risk factors.

V617F-independent upregulation of JAK2 gene expression in patients with inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is one of the most important immune-mediated disorders of the gastrointestinal tract. Besides, IBD is associated with numerous extraintestinal complications such as venous thromboembolism (VTE), an important risk factor for vascular complications, which results in the increased morbidity and mortality. The JAK2 (Janus kinase 2) V617F mutation is a well-known point mutation which is involved in the pathogenesis of IBD, and VTE. Therefore, the aims of this study were to evaluate expression of JAK2 and association of V617F mutation in JAK2 of Iranian patients with IBD.

METHODS

Two hundred and forty-six patients with IBD (209 UC and 37 CD) and 206 healthy controls were enrolled in this study. The genomic DNA and total RNA were extracted from peripheral blood mononuclear cells (PBMCs). Then, the JAK2 V617F mutation detection was performed using the restriction fragment length polymorphism (RFLP) method. In addition, the JAK2 mRNA expression was evaluated using a quantitative polymerase chain reaction (q-PCR) using the SYBR Green assay.

RESULTS

There was no association of V61F mutation in patients with IBD with or without thrombosis compared with healthy control. However, the relative mRNA expression of JAK2 was significantly upregulated in patients with IBD in comparison with healthy control (P < 0.0001). In addition, the JAK2 mRNA expression was significantly decreased in patients with IBD having thrombosis compared with those without thrombosis ( P < 0.0001).

CONCLUSIONS

Taken together our findings suggested that JAK2 V61F-independent upregulation of JAK2 mRNA expression in patients with IBD. Moreover, despite the absence of JAK2 V617F mutation in patients with IBD, the increased gene expression of JAK2 can be explained by another molecular mechanism such as regulation of gene expression at the transcriptional level which may play crucial roles in the pathogenesis of IBD.

Assessment of Anti-Tissue Type Plasminogen Activator Antibodies in Patients With Prosthetic Heart Valve Thrombosis: The ATA Trial

BACKGROUND

Thrombolysis is an effective treatment strategy for prosthetic valve thrombosis (PVT). Recombinant tissue-type plasminogen activator (rt-PA) is widely used as a thrombolytic agent. Infusion of rt-PA may trigger the production of anti-tissue plasminogen activator (tPA) antibodies (ATAs). We aimed to evaluate the possible relationship between ATA levels and PVT formation, and the role of baseline ATA levels on outcomes of thrombolytic therapy in patients with PVT.

METHODS

This prospective, single-center cohort study included 28 patients with PVT undergoing thrombolysis and 31 controls with normal prostheses. Plasma samples were collected from patients with PVT at baseline and at 15th, 30th, 90th, and 180th days after thrombolysis and from controls at baseline only. The ATA levels were assessed in human plasma by an enzyme-linked immunosorbent assay.

RESULTS

Baseline ATA-immunoglobulin (Ig) G and IgM were significantly higher in patients with PVT than in controls. The levels of IgM and IgG peaked at 15th and 30th days after rt-PA infusion, respectively. Subtherapeutic international normalized ratio and baseline ATA-IgM were independent predictors of PVT. Thrombolysis failed in 6 patients (21%) in whom baseline IgM levels were significantly higher than successfully lysed patients. Rethrombosis occurred in 9 patients (32%) in whom baseline IgG levels were significantly higher than those without rethrombosis. There was a moderate positive correlation between baseline and 15th-day IgM levels and the dose of rt-PA needed for successful lysis.

CONCLUSION

The ATA levels tended to be higher in patients with PVT at the time of initial diagnosis compared to controls without PVT. In addition, such patients with PVT and high ATA levels may be at high risk for failed thrombolysis or rethrombosis.

Activation of Blood Coagulation in Two Prototypic Autoimmune Skin Diseases: A Possible Link with Thrombotic Risk

Coagulation activation has been demonstrated in two prototypic autoimmune skin diseases, chronic autoimmune urticaria and bullous pemphigoid, but only the latter is associated with increased thrombotic risk. Two markers of coagulation activation (prothrombin fragment F1+2 and fibrin fragment D-dimer) were measured by immunoenzymatic methods in plasma samples from 30 patients with active chronic autoimmune urticaria, positive for autologous serum skin test, 30 patients with active bullous pemphigoid and 30 healthy subjects. In skin biopsies, tissue factor expression was evaluated by both immunohistochemistry and in situ hybridization. F1+2 and D-dimer levels were higher in active chronic autoimmune urticaria (276.5±89.8 pmol/L and 5.56±4.40 nmol/L, respectively) than in controls (145.2±38.0 pmol/L and 1.06±0.25 nmol/L; P=0.029 and P=0.011) and were much higher in active bullous pemphigoid (691.7±318.7 pmol/L and 15.24±9.09 nmol/L, respectively) (P<0.0001). Tissue factor positivity was evident in skin biopsies of both disorders with higher intensity in bullous pemphigoid. F1+2 and D-dimer, during remission, were markedly reduced in both disorders. These findings support the involvement of coagulation activation in the pathophysiology of both diseases. The strong systemic activation of coagulation in bullous pemphigoid may contribute to increase the thrombotic risk and provides the rationale for clinical trials on anticoagulant treatments in this disease.

The relationship between coagulation state and inflammatory bowel disease: current understanding and clinical implications

Inflammatory bowel disease (IBD) is associated with a hypercoagulable state and subsequently with an increased risk for venous thromboembolism (VTE). VTE in IBD is characterized by a high recurrence rate and is associated with the disease activity. Acquired endothelial dysfunction, abnormalities of platelets, activation of coagulation system and impaired fibrinolysis are the main changes in the coagulation state in IBD. The development of VTE in IBD has been considered to be the result of multiple interactions between acquired and inherited risk factors. The treatment of VTE in IBD patients is recommended to be similar and to follow the same protocols as for non-IBD patients. In the clinical practice, the management of IBD patients and especially the hospitalized patients should include thromboprophylaxis.

Inflammatory bowel disease: epidemiology, pathology and risk factors for hypercoagulability

Hypercoagulability observed in patients with inflammatory bowel diseases (IBD) may lead to thromboembolic events (TE), which affect the venous and arterial systems alike and are an important factor in patients' morbidity and mortality. The risk of TE in IBD patients has been demonstrated to be approximately three-fold higher as compared to the general population. The pathogenesis of thrombosis in IBD patients is multifactorial and not fully explained. The most commonly listed factors include genetic and immune abnormalities, disequilibrium between procoagulant and anticoagulant factors, although recently, the role of endothelial damage as an IBD-triggering factor is underlined. Several studies report that the levels of some coagulation enzymes, including fibrinogen, factors V, VII, VIII, active factor XI, tissue factor, prothrombin fragment 1 + 2 and the thrombin-antithrombin complex, are altered in IBD patients. It has been demonstrated that there is a significant decrease of tissue plasminogen activator level, a marked increase of plasminogen activator inhibitor type 1 and thrombin-activable fibrinolysis inhibitor, a significantly lower level of antithrombin III and tissue factor pathway inhibitor. IBD patients have been also observed to produce an increased amount of various anticoagulant antibodies. Hyperhomocysteinemia, which is a potential risk factor for TE was also observed in some IBD patients. Further studies are necessary to assess the role of coagulation abnormalities in IBD etiology and to determine indications for thromboprophylactic treatment in patients at high risk of developing TE.

Cerebral arterial infarction in inflammatory bowel diseases

It has been estimated that up to 10% of hypercoagulable state manifestations in patients with inflammatory bowel disease (IBD) are ischemic strokes. The literature search through MEDLINE and EMBASE highlighted 33 case reports of IBD patients complicated with cerebral arterial infarction during the course of their disease. Most of these patients presented with either left or right sided hemiparesis on admission, while the most common site of arterial infarction was either the right or the left middle cerebral artery. Thrombocytosis and anemia were the most commonly observed potential risk factors for stroke in the laboratory analysis. Other coagulation abnormalities, hereditary thrombotic mutations, hyperhomocysteinemia, hyperlipidemia, structural cardiac abnormalities, endocarditis and cerebral artery vasculitis have also been reported in some of the cases that were reviewed. Even though many of these findings are commonly observed in IBD patients, literature data is still controversial about their causal relationship to ischemic stroke. Similarly, there is also lack of steady evidence and official guidelines for stroke management in both children and adults with IBD comorbidity. Finally, an algorithm based on both the American Heart Association and European Stroke Organization guidelines for stroke management and prevention in the general population, is presented as a reference point for the treatment of IBD patients who are complicated by an ischemic cerebral event.

Assessment of anti-prothrombin antibodies in thrombosis complicating inflammatory bowel diseases

PURPOSE

In inflammatory bowel diseases (IBD), risk of thrombosis and production of antibodies are increased. In autoimmune and inflammatory disorders, a role of anti-prothrombin (aPT) antibodies in developing thrombosis has been hypothesised. The aim of the study is to evaluate the prevalence of aPT antibodies in IBD patients, with and without thrombosis.

METHODS

Thirty-three IBD patients with thrombosis, 33 IBD patients without thrombosis matched for sex, age, diagnosis and disease activity and 66 sex- and age-matched healthy controls were enrolled. Thrombosis was considered recent when blood sample was obtained within 3 months from the event.

RESULTS

Prevalence of aPT antibodies in thrombotic IBD patients (3/33, 9.1 %), non-thrombotic IBD patients (4/33, 12.1 %) and in healthy subjects (3/66, 4.5 %) did not result significantly different (p = 0.377). The prevalence of aPT antibodies was more frequent in ulcerative colitis (6/32, 18.7 %) than in Crohn's disease (1/34, 2.9 %) and healthy controls (p = 0.022). Among thrombotic IBD patients, the prevalence of aPT antibodies was higher in those with recent (2/9, 22.2 %) than in those with previous thrombosis (1/24, 4.2 %) (p = 0.103). All thrombotic IBD patients with aPT antibodies were affected by ulcerative colitis with previous history of deep venous thrombosis.

CONCLUSIONS

aPT antibodies do not appear to play a relevant role in thrombosis complicating IBD course. A possible association in ulcerative colitis patients with DVT could not be excluded.

Prothrombotic state and impaired fibrinolysis in bullous pemphigoid, the most frequent autoimmune blistering disease

Bullous pemphigoid (BP) is a potentially life-threatening autoimmune blistering disease that is burdened with an increased risk of cardiovascular events. In BP, there is an interplay between inflammation and coagulation both locally, which contributes to skin damage, and systemically, which leads to a prothrombotic state. Fibrinolysis is an important defence mechanism against thrombosis, but has only been studied locally in BP and no systemic data are available. The aim of this observational study was to evaluate systemic fibrinolysis and coagulation activation in patients with BP. We measured parameters of fibrinolysis and coagulation by immunoenzymatic methods in plasma from 20 patients with BP in an active phase and during remission after corticosteroid treatment. The controls were 20 age- and sex-matched healthy subjects. Plasma levels of plasminogen activator inhibitor type 1 (PAI-1) antigen, PAI-1 activity and tissue plasminogen activator (t-PA) antigen were significantly higher in the BP patients with active disease than in healthy controls (P = 0·0001 for all), as were the plasma levels of the fibrin fragment d-dimer and prothrombin fragment F1+2 (P = 0·0001 for both). During remission after treatment, levels of PAI-1 antigen and PAI-1 activity decreased significantly (P = 0·008 and P = 0·006, respectively), and there was also a significant decrease in plasma levels of d-dimer (P = 0·0001) and F1+2 (P = 0·0001). Fibrinolysis is inhibited in patients with active BP, due mainly to an increase in plasma levels of PAI-1. Corticosteroids not only induce the regression of BP lesions, but also reduce the inhibition of fibrinolysis, which may contribute to decreasing thrombotic risk.

Anti-t-PA antibodies in acute myocardial infarction after thrombolysis with rt-PA

BACKGROUND

Thrombolysis with recombinant tissue-type plasminogen activator (rt-PA) is successfully used in acute myocardial infarction with ST elevation (STEMI). Reocclusions follow rt-PA treatment in up to 30% of patients within one year. The infusion of rt-PA may induce the production of anti-t-PA antibodies which could interfere with the function of the native t-PA molecule.

METHODS

In order to detect and characterise anti-t-PA antibodies, plasma samples were collected from 30 STEMI patients (20 treated and 10 not treated with rt-PA) at baseline before rt-PA infusion and then 15, 30, 90 and 180 days after STEMI and from 40 healthy subjects at baseline only. Immunoenzymatic, chromatographic and chromogenic methods were employed.

RESULTS

An increase of anti-t-PA antibodies was observed 15 days (IgM, p=0.0001) and 30 days (IgG, p=0.0001) after rt-PA infusion. Six patients had large increases of anti-t-PA IgG which bound the catalytic domain of t-PA (two cases) or kringle 2 domain (four cases), were of IgG1 or IgG3 subclasses and interacted with the t-PA molecule in fluid phase.

CONCLUSION

The infusion of rt-PA may induce the production of specific antibodies that bind active sites of t-PA, thus potentially reducing its in vivo function.

Plasma thrombin-activatable fibrinolysis inhibitor and plasminogen activator inhibitor-1 levels in inflammatory bowel disease

BACKGROUND

Patients with inflammatory bowel disease (IBD) have an increased risk of thromboembolic events. Imbalance of fibrinolysis has been suggested as one of the possible pathogenetic mechanisms. As plasminogen activator inhibitor-1 (PAI-1) and thrombin-activatable fibrinolysis inhibitor (TAFI) are inhibitors of fibrinolysis, we studied TAFI as well as PAI-1 plasma levels in IBD patients compared with healthy controls.

METHODS

A total of 132 IBD patients [68 ulcerative colitis (UC) and 64 Crohn's disease (CD)] and 50 healthy controls were enrolled. PAI-1 and TAFI plasma levels were assessed by commercially available enzyme-linked immunosorbent assay kits. Their relationship with clinical parameters of UC and CD was assessed.

RESULTS

Mean plasma PAI-1 levels were significantly higher in both UC patients (3.9+/-1.3 IU/ml) and CD patients (4.0+/-1.5 IU/ml) compared with healthy controls (3.1+/-1.1 IU/ml) (P=0.01). On the other hand, mean plasma TAFI levels were significantly lower in both UC patients (14.7+/-3.1 microg/ml) and CD patients (13.3+/-3.4 microg/ml) compared with healthy controls (17.4+/-3.0 microg/ml) (P<0.0001). Patients with active disease had significantly higher PAI-1 levels compared with patients with inactive disease for both diseases (P=0.03 and P=0.01, respectively). No significant association between plasma TAFI levels and disease activity was also found. Plasma TAFI levels were significantly lower in patients with ileal CD compared with patients with colonic CD.

CONCLUSION

PAI-1 plasma levels are increased whereas TAFI levels are decreased in IBD patients. These results suggest an imbalance of fibrinolysis in IBD.

Associations of seroreactivity against crystallin proteins with disease activity and cataract in patients with uveitis

PURPOSE

betaB1-crystallin is a putative target of an autoantibody observed in a subset of patients with uveitis. The purpose of this study was to determine whether seroreactivity against betaB1 or other specific purified crystallin proteins is observed in patients with uveitis and whether this reactivity is associated with either cataract or active intraocular inflammation.

METHODS

Sera from patients with uveitis were tested for IgG antibodies with reactivity against alphaA-, alphaB-, betaB1-, or betaB2-crystallin proteins using a modified slot-blot protocol. Ophthalmic evaluations included analysis of the degree of intraocular inflammation and assessment of lens opacity by the Lens Opacities Classification System (LOCS) III. Positive anti-crystallin reactivity was defined as greater than the mean + 2 SD of the reactivity of a commercially available control serum panel. Statistical analysis was performed with the Fisher exact test, Kruskal-Wallis test, and Student's t-test.

RESULTS

IgG antibodies against alphaA-, alphaB-, or betaB1-crystallin were identified in 70% of 39 subjects; in contrast, only 30% of the control sera exhibited reactivity against one or more of these crystallin proteins (P <or= 0.01). Seroreactivity against alphaA-, alphaB-, or betaB1-, but not betaB2-crystallin was related to active anterior segment inflammation. Seroreactivity against alphaB and betaB1 was significantly related to cortical cataract (P <or= 0.05).

CONCLUSIONS

Serum antibodies against specific crystallin proteins are present in most patients with uveitis. The relationship between the presence of specific anti-crystallin antibodies and active inflammation may indicate a role for these autoantibodies in uveitis pathogenesis.

Autoantibodies to plasminogen and tissue plasminogen activator in women with recurrent pregnancy loss

Reduced fibrinolytic activity has been described in primary anti-phospholipid syndrome (PAPS), and may be responsible for thrombotic events. Antibodies to tissue type plasminogen activator (t-PA) or plasminogen (PLG) might contribute to the hypofibrinolytic state in autoimmune diseases, but the clinical significance of these antibodies is still unclear in recurrent pregnancy loss (RPL). The aim of this study is to evaluate the prevalence and clinical significance of anti-PLG and anti-t-PA antibodies in 87 patients with a history of RPL: 54 women with well-defined PAPS (mean age 32.5 years; range 26-38) and 33 women with unexplained RPL (mean age 30 years; range 24-39). IgG anti-PLG antibodies were found in 20 and four patients from the group with RPL/PAPS and unexplained RPL, respectively; IgG anti-t-PA antibodies were found in 11 and two patients from the above two groups, respectively. IgG anti-PLG antibodies were associated with the high risk of RPL (OR 7.2, P = 0.004), especially with RPL/PAPS (OR 11.2, P < 0.001) evaluated by Fisher's exact test, while IgG anti-t-PA were associated with RPL/PAPS (OR 10.0, P = 0.01) but not with RPL (OR 6.8, P = 0.06). A significant inhibition of exogenous fibrinolysis was observed by IgG fractions from patients with anti-PLG or anti-t-PA antibodies on microplates and on the human umbilical vein endothelial cells, compared with those from healthy controls. The prevalence of IgG anti-PLG antibodies was high in RPL patients, especially in RPL/PAPS, while the prevalence of IgG anti-t-PA antibodies was high in RPL/PAPS but not in RPL, and some of them might inhibit fibrinolysis in patients.

Inflammation and coagulation in inflammatory bowel disease: The clot thickens

Inflammation and coagulation play crucial roles in the pathogenesis of multiple chronic inflammatory disorders. Growing evidence highlights a tight mutual network in which inflammation, coagulation, and fibrinolysis play closely related roles. Crohn's disease (CD) and ulcerative colitis (UC), the two major forms of inflammatory bowel disease (IBD), are chronic inflammatory conditions, characterized by a hypercoagulable state and prothrombotic conditions, and accompanied by abnormalities in coagulation. From a pathophysiological point of view, cells and molecules classically implicated in the physiological process of coagulation have now been shown to behave abnormally in IBD and possibly to also play an active role in disease pathogenesis and/or disease progression. This paper reviews studies performed on the coagulation profile and risk factors for thrombosis in IBD. In particular, an overview is provided of the epidemiology, clinical features, and etiology of thromboembolic complications in IBD. Furthermore, we review hemostatic abnormalities in IBD, as well as the cell types involved in such processes. Finally, we highlight the coagulation system as a dynamic participant in the multifaceted process of chronic intestinal inflammation. Overall, an overview is provided that the coagulation system represents an important, though previously underestimated, component of IBD pathogenesis, and may be a possible target for therapeutic intervention.