Antiphospholipid-exposed trophoblast-derived extracellular vesicles express elevated levels of TLR7/8-activating microRNAs and induce endometrial endothelial activation, in part, through TLR7.

Women with antiphospholipid syndrome (APS) are at high risk for miscarriage and preeclampsia. Unlike pro-thrombotic systemic APS, obstetric APS is associated with insufficient placentation, as well as inflammation and vascular dysfunction at the maternal-fetal interface. Antiphospholipid antibodies (aPL) can target the placental trophoblast and induce inflammation. We reported that aPL trigger trophoblast cells to produce elevated levels of IL-8 through activation of Toll-like receptor 4 (TLR4). Downstream of TLR4, we found this IL-8 response is mediated by a TLR8-activating microRNA (miR), miR-146a-3p, which is also released by the trophoblast via extracellular vesicles (EVs). Since endothelial dysfunction is a feature of obstetric APS, we sought to determine if other miRs that can activate the RNA sensors, TLR7 and/or TLR8, are released by the trophoblast via EVs after exposure to aPL, and if these EVs can activate human endometrial endothelial cells (HEECs). Using a human first trimester extravillous trophoblast cell line we found that aPL elevated their release of small EVs (<150 nm). These extracellular vesicles released from trophoblast cells exposed to aPL expressed elevated levels of TLR7/8-activating miR-21a and miR-29a, in addition to the previously reported miR-146a-3p. Extracellular vesicles from aPL-exposed human trophoblast cells triggered human endometrial endothelial cells to generate an inflammatory IL-8 response, in part through TLR7. This study highlights EVs as a mode of communication between the placenta and the maternal vasculature, as well as a potential role for TLR7/8-activating miRs in contributing to inflammation at the maternal-fetal interface in obstetric APS.

Exosomal miR-146a-5p derived from human umbilical cord mesenchymal stem cells can alleviate antiphospholipid antibody-induced trophoblast injury and placental dysfunction by regulating the TRAF6/NF-κB axis.

Exosomes originating from human umbilical cord mesenchymal stem cells (hucMSC-exos) have become a novel strategy for treating various diseases owing to their ability to regulate intercellular signal communication. However, the potential of hucMSC-exos to improve placental injury in obstetric antiphospholipid syndrome and its underlying mechanism remain unclear. Our objective was to explore the potential application of hucMSC-exos in the treatment of obstetric antiphospholipid syndrome and elucidate its underlying mechanism. In our study, hucMSC-exos ameliorated the functional impairment of trophoblasts caused by antiphospholipid antibodies in vitro and attenuated placental dysfunction in mice with obstetric antiphospholipid syndrome by delivering miR-146a-5p. Exosomal miR-146a-5p suppressed the expression of tumor necrosis factor receptor-associated factor 6 (TRAF6) and inhibited the activation of NF-κB signaling, leading to the down-regulation of IL-1ß and IL-18 to rescue inflammation and modulation of Cleaved-CASP3, BAX, and BCL2 to inhibit apoptosis in HTR8/SVneo cells and mice placenta. This study identified the potential molecular basis of how hucMSC-exos improved antiphospholipid antibody-induced placental injury and highlighted the functional importance of the miR-146a-5p/TRAF6 axis in the progression of obstetric antiphospholipid syndrome. More importantly, this study provided a fresh outlook on the promising use of hucMSC-exos as a novel and effective treatment approach in obstetric antiphospholipid syndrome.

Antiphospholipid Antibodies Increase Endometrial Stromal Cell Decidualization, Senescence, and Inflammation via Toll-like Receptor 4, Reactive Oxygen Species, and p38 MAPK Signaling.

OBJECTIVE: Miscarriage affects 1 in 7 pregnancies, and antiphospholipid autoantibodies (aPLs) are one of the biggest risk factors for recurrent pregnancy loss. While aPLs target the endometrial stroma, little is known about their impact. Endometrial stromal cells (EnSCs) undergo decidualization each menstrual cycle, priming the uterus to receive implanting embryos. Thus, appropriate decidualization and EnSC function is key for establishment of a successful pregnancy. This study was undertaken to explore the effects of aPL on EnSC decidualization, senescence, and inflammation. METHODS: EnSCs under decidualizing conditions were exposed to aPL or control IgG alone or in the presence of either a Toll-like receptor 4 (TLR-4) antagonist, a p38 MAPK inhibitor, a reactive oxygen species (ROS) inhibitor, low molecular weight heparin (LMWH), or acetyl salicylic acid. Secretion of decidualization markers and inflammatory interleukin-8 were quantified by enzyme-linked immunosorbent assay, and senescence-associated ß-galactosidase activity was evaluated. In a mouse model of decidualization, aPL or control IgG was administered, and uterine expression levels of decidualization and inflammatory markers were quantified by real-time quantitative polymerase chain reaction. RESULTS: Antiphospholipid antibodies increased human EnSC decidualization, senescence, and inflammation. This phenotype was recapitulated in the mouse model. The decidualization and inflammatory responses were partially mediated by TLR-4 and p38 MAPK, while the decidualization and senescence responses were ROS-dependent. LMWH, commonly used to treat aPL-positive women at risk of obstetric complications, reduced the ability of aPL to increase EnSC decidualization and inflammation. CONCLUSION: These findings shed new light on the pathogenesis of pregnancy complications in women with aPLs and underscore the benefit of heparin in preventing pregnancy loss in this high-risk population.

High Incidence of Antiphospholipid Antibodies in Newly Diagnosed Patients With Lymphoma and a Proposed aPL Predictive Score.

Given that the presence of antiphospholipid (aPL) antibodies has been proposed to be associated with thrombosis in newly diagnosed patients with lymphoma, we conducted a prospective cohort study on these patients. In all, 154 patients were enrolled. More than half were advanced-stage diffuse large B-cell lymphoma. Approximately one-third (35.7%) of the patients had the presence of aPLs, with single-, double-, and triple-aPL positivities of 29.9%, 5.2%, and 0.6%, respectively. Of the 154 patients, 8 (5.19%) developed symptomatic thrombosis during follow-up. There were no significant differences in the incidences of thrombosis for the aPL-positive and aPL-negative groups (5.5% vs 5.1%; P = 1.000). In a multivariate analysis, patients with male sex and lymphoma stage IV were significant risk factors for aPL positivity, with odds ratio [OR] = 2.22 (95% CI: 1.11-4.45), P = .025, and OR: 2.34 (95% CI: 1.17-4.67), P = .016, respectively. An aPL predictive score of ≥-1 was predictive of aPL positivity, with a sensitivity of 83.6% and specificity of 34.3%.

Amniotic fluid antiphospholipid antibodies: potential role in antiphospholipid syndrome-independent aberrant implantation process.

BACKGROUND: The direct role of antiphospholipid antibodies (aPL) at maternal-fetal interface has not been fully investigated, especially whether they are involved in physiological and pathological implantation conditions, in an antiphospholipid syndrome (APS)-independent manner. In fact, trophoblast cells and placental endothelial cells at the implantation site express potential aPL targeted-phospholipid antigens (PL Ags); thus, the local production and presence of their specific antibodies, not related to APS (characterized by aPL presence in the peripheral blood), could be a potential marker of aberrant invasion, implantation and fetal-maternal immune tolerance processes. METHODS: Anti-Beta2glycoprotein I (anti-ß2GPI) and anticardiolipin (aCL Ab) antibodies (the most clinically relevant aPL) were detected by immunoenzymatic assay (ELISA), in the amniotic fluid (AF) of 167 women with physiological and complicated common pregnancy conditions, sharing an aberrant implantation process, such as recurrent pregnancy loss (RPL), autoimmune hypothyroidism (ahT) and smoking. All women included in the study were negative to peripheral blood aPL. RESULTS: aCL and anti-ß2GPI antibodies were detectable in all the AF samples. RPL, ahT and smoking patients had higher level of anti-ß2GPI Abs (IgM) compared to women with physiological pregnancies (p < 0.0001). Since IgM cannot cross the placenta, their local production in response to maternal-fetal interface stimuli, could be hypothesized. CONCLUSIONS: The presence of aPL in the AF (not related to APS) could reveal a potential clinical significance at maternal-fetal interface in selected pregnancy complications, in which an aberrant implantation process, and in turn an impaired fetal-maternal immune tolerance cross-talk, could occur.

Lucio phenomenon mimicking antiphospholipid syndrome: The occurrence of antiphospholipid antibodies in a leprosy patient.

Lucio phenomenon is an atypical reaction of leprosy, characterized by vasculitic lesions that can mimic antiphospholipid syndrome (APS) clinically. Distinguishing the two can be difficult as antiphospholipid autoantibodies may be present in patients with leprosy. We report on a 32-year-old female patient presenting with a sudden onset of fever, hemorrhagic bullae, and skin necrosis on her lower legs. She was treated for APS due to the presence of antiphospholipid antibodies but had an inadequate response. A skin biopsy revealed thrombotic vasculopathy and necrotizing vasculitis associated with aggregation of foam cells in the perivascular area and subcutis, with acid-fast bacilli in the histiocytes and blood vessel walls. Direct immunofluorescence showed IgM, C3, and fibrinogen deposition in the superficial and deep dermal blood vessels. The pathology confirmed the diagnosis of Lucio phenomenon, and appropriate therapy was given. It is essential to evaluate the patient comprehensively, including clinical, serological, and pathological aspects, to obtain the correct diagnosis.

Antiphospholipid antibodies associated with nodal marginal zone lymphoma and its progression to diffuse large B-cell lymphoma-A case report.

An association between autoimmune events, as well as the development of antiphospholipid (aPL) antibodies and lymphoproliferative disorders is well recognized. We present the patient with coagulation abnormalities and non-Hodgkin lymphoma (NHL), primarily diagnosed as nodal marginal zone B-cell lymphoma (NMZL), and in relapse as diffuse large B-cell lymphoma (DLBCL). In the follow-up period, the patient simultaneously developed different aPL antibodies. The presence of aPL antibodies in NHL is frequent but it is not common in the NMZL. The aim of the present case report is to highlight the possible underlying increase of aPL antibodies in NMZL patients with coagulation tests abnormalities.

Role of NOD2 in antiphospholipid antibody-induced and bacterial MDP amplification of trophoblast inflammation.

Women with antiphospholipid antibodies (aPL) are at high risk for pregnancy complications, such as preeclampsia. We previously demonstrated that aPL recognizing ß2GPI promote an extravillous trophoblast pro-inflammatory, anti-migratory and anti-angiogenic profile similar to that seen in preeclampsia. Since preeclampsia in the absence of aPL may have an underlying infectious element, women with aPL may be at increased risk for preeclampsia or other adverse outcomes if an infection is present. Our objective was to determine the impact the common bacterial component, muramyl dipeptide (MDP), has on trophoblast responses to aPL. Herein, we report that bacterial MDP amplifies trophoblast IL-1ß expression, processing, and secretion in the presence of aPL through activation of NOD2. In the absence of MDP, NOD2 also mediates anti- ß2GPI antibody-induced trophoblast IL-1ß and VEGF secretion. Additionally, we report a role for extravillous trophoblast vimentin as a novel danger signal that contributes to the aPL-induced trophoblast IL-1ß production. Together our data indicate that NOD2 mediates trophoblast inflammatory and angiogenic responses to aPL alone, and mediates trophoblast inflammation in the presence of bacterial MDP. These findings suggest that a bacterial infection at the maternal-fetal interface may exacerbate the impact aPL have on trophoblast inflammation and, thus, on pregnancy outcome.

Antiphospholipid Syndrome Nephropathy: From Pathogenesis to Treatment.

Kidney damage is a well-recognized complication of the antiphospholipid syndrome (APS), either primary or systemic lupus erythematosus (SLE)-associated APS. Kidney involvement in APS involves a variety of manifestations, such as renal artery thrombosis or stenosis, renal vein thrombosis, allograft loss due to thrombosis after kidney transplantation, and injury to the renal microvasculature, also known as APS nephropathy. Biopsy in patients with APS nephropathy includes acute thrombotic microangiopathy lesions and chronic intrarenal vascular lesions such as interlobular fibrous intimal hyperplasia, arterial and arteriolar recanalizing thrombosis, fibrous arterial occlusion, and focal cortical atrophy. The most frequent clinical features are hypertension, microscopic hematuria, proteinuria (ranging from mild to nephritic levels), and renal insufficiency. It is uncertain whether antiphospholipid antibodies or other factors are implicated in the development of APS nephropathy, and whether it is driven mainly by thrombotic or by inflammatory processes. Experimental models and clinical studies of thrombotic microangiopathy lesions implicate activation of the complement cascade, tissue factor, and the mTORC pathway. Currently, the management of APS nephropathy relies on expert opinion, and consensus is lacking. There is limited evidence about the effect of anticoagulants, and their use remains controversial. Treatment approaches in patients with APS nephropathy lesions may include the use of heparin based on its role on complement activation pathway inhibition or the use of intravenous immunoglobulin and/or plasma exchange. Targeted therapies may also be considered based on potential APS nephropathy pathogenetic mechanisms such as B-cell directed therapies, complement inhibition, tissue factor inhibition, mTOR pathway inhibition, or anti-interferon antibodies, but prospective multicenter studies are needed to address their role.

The diagnosis and clinical management of the catastrophic antiphospholipid syndrome: A comprehensive review.

The catastrophic antiphospholipid syndrome (CAPS) is a life-threating variant of the antiphospholipid syndrome characterized by the development of multiple thrombosis in a short period of time, usually ending up in the failure of function of several vital organs. Most CAPS episodes are related to a prothrombotic situation or precipitating factor such as infections, surgical procedures or malignant diseases. In patients with CAPS, the development of multiple thrombosis leads to an important cytokine release that worsens the already critical patient's situation. The disease usually involves the kidneys, the lungs and the heart, although any organ system can be affected. Although occasionally the disease affects large vessels, in the majority of cases it affects small vessels, leading to a disseminated microangiopathic syndrome resembling thrombotic thrombocytopenic purpura. Treatment is based on the administration of anticoagulants, corticosteroids, plasma exchange and/or intravenous immunoglobulins. Cyclophosphamide is recommended in those CAPS cases associated to systemic lupus erythematosus. Additionally, rituximab and eculizumab have been used in refractory cases. Mortality is still around 30% despite current treatment.

Therapy for antiphospholipid miscarriages: Throwing the baby out with the bathwater?

PROBLEM: The association of low molecular weight heparin (LMWH) with low-dose aspirin (LDASA) provides the therapeutic cornerstone of obstetric anti-phospholipid syndrome (APS). This combo approach is not effective in all patients, and few women still experience recurrences. METHOD OF STUDY: In an elegant in vitro study, Chiombori Quao and colleagues demonstrated that anti-phospholipid antibodies (aPL) affect the functionality of endometrial endothelial cells interfering with angiogenesis. LMWH and LDASA, in combination or alone, did not display any protective activity but exacerbated aPL-mediated effects. RESULTS: The above data were advocated as a demonstration of the inefficacy of LMWH and LDASA in obstetric APS. Given the lack of thrombotic lesions in APS placentae, this treatment is mainly empirical. However, clinical practice clearly shows that LMWH and LDASA are effective in most patients. Non-responsive women represent a peculiar subgroup, with a high-risk aPL profile. All experimental models, including in vitro models of obstetric APS, display limitations that should be considered before translating data to patients. In particular, the use of a monoclonal antibody specific for Domain (D) 5 does not fit with the evidence that anti-D1, but not anti-D4,5, are associated with both vascular and obstetric APS manifestations. CONCLUSION: The association of LMWH and LDASA is the most effective therapeutic option for pregnant aPL-positive women. The lack of a clear demonstration of the pharmacological action of LMWH/LDASA should urge to further invtrestigate the pathophysiology of aPL-associated miscarriages.

CD39 and CD73 activity are protective in a mouse model of antiphospholipid antibody-induced miscarriages.

OBJECTIVE: Antiphospholipid syndrome (APS) is a systemic autoimmune disorder of young adults associated with devastating pregnancy complications (recurrent miscarriages, preeclampsia and low birth weight) and vascular complications including thrombosis. The key components implicated in pathogenesis of APS are the complement cascade and tissue factor (TF) activity causing inflammation and coagulation. Purinergic signalling involving catabolism of ATP to adenosine by cell-surface enzymes CD39 and CD73 has anti-inflammatory and anti-thrombotic effects. We studied whether activities of CD39 and CD73 are important in preventing the development of miscarriages in APS. METHODS: We studied frequency of miscarriages and decidual pathology following passive transfer of human aPL-ab to pregnant wildtype mice, and mice deficient in CD39 and CD73, and also transgenic mice exhibiting 2-3X higher CD39 activity. RESULTS: aPL-ab infusion in pregnant CD39-or CD73-knockout mice triggers an increase in miscarriages, associated with increased TF expression and complement deposition as well as elevated oxidative stress and pro-inflammatory TNF-α and IL-10 expression within the placental decidua. In contrast, aPL-ab induced miscarriages are prevented in mice over-expressing CD39, with reduced decidual TF expression and C3d deposition, diminished lipid peroxidation (4-hydroxynonenal or 4-HNE positive lipid adducts), and reduced TNF-α expression. CONCLUSION: We demonstrate a protective role for CD39 in APS and provide rationale for both the development of endothelial cell-targeted soluble CD39 as a novel therapeutic for APS and analysis of perturbations in the purinergic pathway to explain human disease.

Low molecular weight heparin and aspirin exacerbate human endometrial endothelial cell responses to antiphospholipid antibodies.

PROBLEM: Women with antiphospholipid antibodies (aPL) are at risk for pregnancy complications despite treatment with low molecular weight heparin (LMWH) or aspirin (ASA). aPL recognizing beta2 glycoprotein I can target the uterine endothelium, however, little is known about its response to aPL. This study characterized the effect of aPL on human endometrial endothelial cells (HEECs), and the influence of LMWH and ASA. METHOD OF STUDY: HEECs were exposed to aPL or control IgG, with or without low-dose LMWH and ASA, alone or in combination. Chemokine and angiogenic factor secretion were measured by ELISA. A tube formation assay was used to measure angiogenesis. RESULTS: aPL increased HEEC secretion of pro-angiogenic VEGF and PlGF; increased anti-angiogenic sFlt-1; inhibited basal secretion of the chemokines MCP-1, G-CSF, and GRO-α; and impaired angiogenesis. LMWH and ASA, alone and in combination, exacerbated the aPL-induced changes in the HEEC angiogenic factor and chemokine profile. There was no reversal of the aPL inhibition of HEEC angiogenesis by either single or combination therapy. CONCLUSION: By aPL inhibiting HEEC chemokine secretion and promoting sFlt-1 release, the uterine endothelium may contribute to impaired placentation and vascular transformation. LMWH and ASA may further contribute to endothelium dysfunction in women with obstetric APS.

[Different Symptoms and Course of Coronary Heart Disease in Men and Women]. / Koronare Herzerkrankung ­ Unterschiede in Symptomatik und Verlauf bei Männern und Frauen.

According to the federal statistical office, cardiovascular disorders are still the leading cause of death in Germany. Chronic ischemic heart disease and acute myocardial infarction are the most important subgroups. In addition to evidence-based and personalized medicine, in recent years gender medicine has been established as an independent research area. Gender differences are evident in the majority of prevalent diseases, including cardiovascular disorders. The following article provides an insight into the diagnostically and therapeutically specific aspects of coronary heart disease in men and women.

Antiphospholipid Antibodies and Renal Impairment Parameters in Diabetic Nephropathy: Preliminary Data.

OBJECTIVE: Antiphospholipid antibodies (aPL Abs) represented an independent factor that was associated with the occurrence and/or progression of nephropathy in patients with antiphospholipid syndrome, but their role in diabetic nephropathy is not elucidated. Therefore, we evaluated the association of aPL Abs with the renal impairment parameters in patients with diabetic nephropathy. METHODS: Concentrations of analyzed antibodies were measured by enzyme-linked immunosorbent assay. RESULTS: Cystatin C and anticardiolipin (aCL) antibodies of the immunoglobulin (Ig) G ( r = .349, P = .004) and the IgM isotype ( r = .316, P = .009) were in positive correlation. The IgG isotype of the aCL Abs was in positive correlation with creatinine ( r = .252, P = .038), urea ( r = .241, P = .048), and uric acid ( r = .271, P = .025). The concentrations of the IgG isotype of the aCL Abs were significantly different between subgroups of patients with diabetic polyneuropathy and patients without this clinical finding (Mann-Whitney, P = .033). CONCLUSION: This is the first report on positive correlation between aCL Abs and renal impairment parameters. Larger studies are necessary for elucidation whether this association is involved in further progression of the disease.

Infertility and miscarriage: common pathways in manifestation and management.

The relationship between miscarriage and fertility is complex. While most healthcare settings treat miscarriage as a problem of subfertility in assisted reproduction units, others believe that miscarriage occurs in super-fertile women. Infertile women undergoing assisted reproduction are at a greater risk of having a miscarriage especially at an advanced age compared with women conceiving naturally. Aberrant expression of immunological factors and chromosomal abnormalities underlie both infertility and miscarriage. Common risk factors include increased maternal age, obesity, smoking, alcohol, pre-existing medical conditions and anatomical abnormalities of the reproductive system. Management pathways of both conditions may be similar with pre-implantation genetic testing and assisted reproductive technology used in both conditions. This paper discusses the synergies and differences between the two conditions in terms of their epidemiology, etiopathogenesis, risk factors and management strategies. The two conditions are related as degrees of severity of reproductive failure with common pathways in manifestation and management.

Inhibition of the mTORC pathway in the antiphospholipid syndrome.

BACKGROUND: Although thrombosis is considered the cardinal feature of the antiphospholipid syndrome, chronic vascular lesions are common, particularly in patients with life-threatening complications. In patients who require transplantation, vascular lesions often recur. The molecular pathways involved in the vasculopathy of the antiphospholipid syndrome are unknown, and adequate therapies are lacking. METHODS: We used double immunostaining to evaluate pathway activation in the mammalian target of rapamycin complex (mTORC) and the nature of cell proliferation in the vessels of patients with primary or secondary antiphospholipid syndrome nephropathy. We also evaluated autopsy specimens from persons who had catastrophic antiphospholipid syndrome. The molecular pathways through which antiphospholipid antibodies modulate the mTORC pathway were evaluated in vitro, and potential pharmacologic inhibitors were also tested in vitro. Finally, we studied the effect of sirolimus in kidney-transplant recipients with the antiphospholipid syndrome. RESULTS: The vascular endothelium of proliferating intrarenal vessels from patients with antiphospholipid syndrome nephropathy showed indications of activation of the mTORC pathway. In cultured vascular endothelial cells, IgG antibodies from patients with the antiphospholipid syndrome stimulated mTORC through the phosphatidylinositol 3-kinase (PI3K)-AKT pathway. Patients with antiphospholipid syndrome nephropathy who required transplantation and were receiving sirolimus had no recurrence of vascular lesions and had decreased vascular proliferation on biopsy as compared with patients with antiphospholipid antibodies who were not receiving sirolimus. Among 10 patients treated with sirolimus, 7 (70%) had a functioning renal allograft 144 months after transplantation versus 3 of 27 untreated patients (11%). Activation of mTORC was also found in the vessels of autopsy specimens from patients with catastrophic antiphospholipid syndrome. CONCLUSIONS: Our results suggest that the mTORC pathway is involved in the vascular lesions associated with the antiphospholipid syndrome. (Funded by INSERM and others.).

Antiphospholipid antibodies affect human endometrial angiogenesis: protective effect of a synthetic peptide (TIFI) mimicking the phospholipid binding site of ß(2) glycoprotein I.

PROBLEM: Aim of our study was to investigate whether TIFI, a syntetic peptide able to compete with anti-phospholipid antibodies (aPL) in the binding to endothelium, may restore aPL-inhibited endometrial angiogenesis. METHODS: The protective role of TIFI was evaluated on: i) aPL-inhibited of human endometrial endothelial cells (HEEC) angiogenesis in vitro; ii) aPL-inhibited vascular endothelial growth factor (VEGF) and metalloproteases (MMPs) expression; iii) aPL-inhibited Nuclear Factor-κB (NF-κB) and Extracellular signal-Regulated Kinase (ERK) activation and (iv) angiogenesis in vivo. RESULTS: TIFI restores in a dose-dependent manner: i) aPL-mediated inhibition of HEEC angiogenesis in vitro and in vivo (P < 0.05), ii) VEGF (P < 0.001) and MMP-2 (P < 0.05) expression and iii) NF-κB DNA binding and ERK-1/2 activation (P < 0.05) inhibited by aPL. CONCLUSION: Our results show for the first time the protective effects of TIFI, as represented by its ability to interfere with aPL mediated anti-angiogenic activity.

Both NF-κB and c-Jun/AP-1 involved in anti-ß2GPI/ß2GPI-induced tissue factor expression in monocytes.

Our previous data has demonstrated that Toll-like receptor 4 (TLR4) and its signalling pathway can contribute to anti-ß2-glycoprotein I/ß2-glycoprotein I (anti-ß2GPI/ß2GPI) -induced tissue factor (TF) expression in human blood monocytes and acute monocytic leukaemia cell line THP-1. However, its downstream nuclear transcription factors have not been well explored. In the current study, we further investigated whether nuclear factor kappa B (NF-κB) and activator protein (AP-1) were activated and their roles in anti-ß2GPI/ß2GPI complex stimulating TF expression. The results showed that treatment of the cells with anti-ß2GPI (10µg/ml)/ß2GPI (100 mg/ml) complex could markedly increase the levels of phosphorylated NF-κB (p-NF-κB p65) and c-Jun/AP-1 (p-c-Jun), as well as TF expression. Both NF-κB inhibitor PDTC (20 µM) and AP-1 inhibitor curcumin (25 mM) could attenuate TF expression induced by anti-ß2GPI/ß2GPI or APS-IgG/ß2GPI complex. Combination of any two inhibitors of MAPKs (SB203580/U0126 or SB203580/SP600125 or U0126/SP600125) could decrease activation of NF-κB. SB203580/SP600125 or U0126/SP600125, but not SB203580/U0126, could reduce the phosphorylation of c-Jun/AP-1. Neither NF-κB nor c-Jun/AP-1 activation caused by anti-ß2GPI/ß2GPI complex could be affected by TLR4 inhibitor TAK-242. In conclusion, our results indicate that both NF-κB and c-Jun/AP-1 can be activated and play important roles in the process of anti-ß2GPI/ß2GPI-induced TF expression in monocytes, thereby contributing to the pathological processes of antiphospholipid syndrome.