Hydroxychloroquine reduces binding of antiphospholipid antibodies to syncytiotrophoblasts and restores annexin A5 expression

Lipid-binding antiphospholipid antibodies: significance for pathophysiology and diagnosis of the antiphospholipid syndrome

The antiphospholipid syndrome (APS) is an autoimmune disease characterized by the presence of pathogenic antiphospholipid antibodies (aPL). Since approximately 30 years ago, lipid-binding aPL, which do not require a protein cofactor, have been regarded as irrelevant for APS pathogenesis even though anticardiolipin are a diagnostic criterion of APS. In this review, we will summarize the available evidence from in vitro studies, animal models, and epidemiologic studies, which suggest that this concept is no longer tenable. Accordingly, we will only briefly touch on the role of other aPL in APS. This topic has been amply reviewed in detail elsewhere. We will discuss the consequences for laboratory diagnostics and future research required to resolve open questions related to the pathogenic role of different aPL specificities.

The Relevance, Predictability, and Utility of Annexin A5 for Human Physiopathology

As an important functional protein molecule in the human body, human annexin A5 (hAnxA5) is widely found in human cells and body fluids. hAnxA5, the smallest type of annexin, performs a variety of biological functions by reversibly and specifically binding phosphatidylserine (PS) in a calcium-dependent manner and plays an important role in many human physiological and pathological processes. The free state hAnxA5 exists in the form of monomers and usually forms a polymer in a specific self-assembly manner when exerting biological activity. This review systematically discusses the current knowledge and understanding of hAnxA5 from three perspectives: physiopathological relevance, diagnostic value, and therapeutic utility. hAnxA5 affects the occurrence and development of many physiopathological processes. Moreover, hAnxA5 can be used independently or in combination as a biomarker of physiopathological phenomena for the diagnosis of certain diseases. Importantly, based on the properties of hAnxA5, many novel drug candidates have been designed and prepared for application in actual medical practice. However, there are also some gaps and shortcomings in hAnxA5 research. This in-depth study will not only expand the understanding of structural and functional relationships but also promote the application of hAnxA5 in the field of biomedicine.

Pregnancy in antiphospholipid syndrome: what should a rheumatologist know?

This review focuses on the management of reproductive issues in women who have antiphospholipid syndrome (APS) or are carriers of antiphospholipid antibodies (aPL). The importance of aPL detection during preconception counselling relies on their pathogenic potential for placental insufficiency and related obstetric complications. The risk of adverse pregnancy outcomes can be minimized by individualized risk stratification and tailored treatment aimed at preventing placental insufficiency. Combination therapy of low-dose acetylsalicylic acid and heparin is the mainstay of prophylaxis during pregnancy; immunomodulation, especially with hydroxychloroquine, should be considered in refractory cases. Supplementary ultrasound surveillance is useful to detect fetal growth restriction and correctly tailor the time of delivery. The individual aPL profile must be considered in the stratification of thrombotic risk, such as during assisted reproduction techniques requiring hormonal ovarian stimulation or during the follow-up after pregnancy in order to prevent the first vascular event.

Deciphering the immunological interactions: targeting preeclampsia with Hydroxychloroquine's biological mechanisms

Preeclampsia (PE) is a complex pregnancy-related disorder characterized by hypertension, followed by organ dysfunction and uteroplacental abnormalities. It remains a major cause of maternal and neonatal morbidity and mortality worldwide. Although the pathophysiology of PE has not been fully elucidated, a two-stage model has been proposed. In this model, a poorly perfused placenta releases various factors into the maternal circulation during the first stage, including pro-inflammatory cytokines, anti-angiogenic factors, and damage-associated molecular patterns into the maternal circulation. In the second stage, these factors lead to a systemic vascular dysfunction with consecutive clinical maternal and/or fetal manifestations. Despite advances in feto-maternal management, effective prophylactic and therapeutic options for PE are still lacking. Since termination of pregnancy is the only curative therapy, regardless of gestational age, new treatment/prophylactic options are urgently needed. Hydroxychloroquine (HCQ) is mainly used to treat malaria as well as certain autoimmune conditions such as systemic lupus and rheumatoid arthritis. The exact mechanism of action of HCQ is not fully understood, but several mechanisms of action have been proposed based on its pharmacological properties. Interestingly, many of them might counteract the proposed processes involved in the development of PE. Therefore, based on a literature review, we aimed to investigate the interrelated biological processes of HCQ and PE and to identify potential molecular targets in these processes.

Antiphospholipid syndrome management: a 2023 update and practical algorithm-based approach

PURPOSE OF REVIEW

Antiphospholipid syndrome (APS) is an acquired thrombo-inflammatory disease that has morbid and sometimes devastating effects on patients and their families. This review will discuss the most recent international societal treatment guidelines and propose practical management algorithms for various APS sub-types.

RECENT FINDINGS

APS represents a disease spectrum. Although thrombosis and pregnancy morbidities are traditional hallmarks of APS, a variety of extra-criteria clinical phenotypes can often be seen, which makes clinical management more challenging. Primary APS thrombosis prophylaxis should take a risk-stratified approach. Although vitamin K antagonists (VKAs) or heparin/low molecular weight heparin (LMWH) remain the preferred treatment for secondary APS thrombosis prophylaxis, some international society guidelines support the use of direct oral anticoagulants (DOACs) in certain circumstances. Careful monitoring and individualized obstetric care with the use of aspirin and heparin/LMWH will improve pregnancy outcomes among pregnant individuals with APS. Treatment of microvascular and catastrophic APS remains challenging. While the addition of various immunosuppressive agents is often utilized, further systemic evaluations of their use are warranted before definitive recommendations can be made. Several new therapeutic strategies are on the horizon that might enable more personalized and targeted APS management in the near future.

SUMMARY

Although the knowledge of APS pathogenesis has grown in recent years, the management principles and strategies are largely unchanged. There is an unmet need for evaluating pharmacological agents, beyond anticoagulants, that target diverse thromboinflammatory pathways.

Hydroxychloroquine as an Immunomodulatory and Antithrombotic Treatment in Antiphospholipid Syndrome

Antiphospholipid syndrome (APS) is an acquired highly prothrombotic disorder in which thrombo-inflammatory antiphospholipid antibodies (aPL) cause thrombosis via multiple mechanisms, including endothelial damage and activation. Obstetric complications in APS are caused by placental thrombosis, inflammation and complement activation. Anticoagulation is poorly effective in some patients especially those with triple positive aPL who are at ~30% risk of thrombosis recurrence within 10 years. Increasing therapeutic anticoagulation intensity may be beneficial but leads to excess bleeding with serious complications, such as intracerebral haemorrhage. Nonetheless, anticoagulation is still the mainstay of treatment despite the autoimmune nature of APS. The antimalarial immunomodulatory drug hydroxychloroquine (HCQ) has been used for many years for the treatment of inflammatory rheumatic diseases. HCQ has complex pleiotropic mechanisms of action upon multiple cell types. The proposed biological processes that HCQ regulates support the hypothesis that it may be a successful adjunctive treatment in the prevention of recurrent thrombosis and pregnancy complications.

Protection by hydroxychloroquine prevents placental injury in obstetric antiphospholipid syndrome

Obstetric antiphospholipid syndrome (OAPS) is mediated by antiphospholipid antibodies (aPLs, and anti‐β2 glycoprotein I antibody is the main pathogenic antibody), and recurrent abortion, preeclampsia, foetal growth restriction and other placental diseases are the main clinical characteristics of placental pathological pregnancy. It is a disease that seriously threatens the health of pregnant women. Hydroxychloroquine (HCQ) was originally used as an anti‐malaria drug and has now shown benefit in refractory OAPS where conventional treatment has failed, with the expectation of providing protective clinical benefits for both the mother and foetus. However, its efficacy and mechanism of action are still unclear. After clinical data were collected to determine the therapeutic effect, human trophoblast cells in early pregnancy were prepared and treated with aPL. After the addition of HCQ, the proliferation, invasion, migration and tubule formation of the trophoblast cells were observed so that the therapeutic mechanism of HCQ on trophoblast cells could be determined. By establishing an obstetric APS mouse model similar to the clinical situation, we were able to detect the therapeutic effect of HCQ on pathological pregnancy. The normal function of trophoblast cells is affected by aPL. Antibodies reduce the ability of trophoblast cells to invade and migrate and can impair tubule formation, which are closely related to placental insufficiency. HCQ can partially reverse these side effects. In the OAPS mouse model, we found that HCQ prevented foetal death and reduced the incidence of pathological pregnancy. Therefore, HCQ can improve pregnancy outcomes and reverse the aPL inhibition of trophoblast disease. In OAPS, the use of HCQ needs to be seriously considered.

Pathogenesis, Diagnosis and Management of Obstetric Antiphospholipid Syndrome: A Comprehensive Review

Antiphospholipid syndrome is an autoimmune disorder characterized by vascular thrombosis and/or pregnancy morbidity associated with persistent antiphospholipid antibody positivity. Cases fulfilling the Sydney criteria for obstetric morbidity with no previous thrombosis are known as obstetric antiphospholipid syndrome (OAPS). OAPS is the most identified cause of recurrent pregnancy loss and late-pregnancy morbidity related to placental injury. Cases with incomplete clinical or laboratory data are classified as obstetric morbidity APS (OMAPS) and non-criteria OAPS (NC-OAPS), respectively. Inflammatory and thrombotic mechanisms are involved in the pathophysiology of OAPS. Trophoblasts, endothelium, platelets and innate immune cells are key cellular players. Complement activation plays a crucial pathogenic role. Secondary placental thrombosis appears by clot formation in response to tissue factor activation. New risk assessment tools could improve the prediction of obstetric complication recurrences or thromboses. The standard-of-care treatment consists of low-dose aspirin and prophylactic low molecular weight heparin. In refractory cases, the addition of hydroxychloroquine, low-dose prednisone or IVIG improve pregnancy outcomes. Statins and eculizumab are currently being tested for treating selected OAPS women. Finally, we revisited recent insights and concerns about the pathophysiology, diagnosis and management of OAPS.

Obstetric anti-phospholipid syndrome: from pathogenesis to treatment

Antiphospholipid syndrome (APS) is an autoimmune disease characterized by clinical manifestations such as thrombosis and obstetric complications with documented persistence of antiphospholipid antibodies (aPLs). Recent studies have revealed that the cause of aPL-related obstetric complications is dysfunction of placental trophoblasts and inflammation of the maternal-fetal interface induced by aPLs, not thrombosis. Although aPLs are associated with recurrence of serious complications during pregnancy, appropriate combination therapy with heparin and low-dose aspirin can improve the course of 70-80% of subsequent pregnancies. Preconception counseling and patient-tailored treatment are fundamental to improving maternal and fetal outcomes. Non-anticoagulant treatments such as hydroxychloroquine and statins are being developed for cases refractory to conventional treatment. Risk factors for thrombosis after pregnancy complications were identified based on the analysis of large databases of obstetric APS.

Effect of hydroxychloroquine on antiphospholipid antibodies-inhibited endometrial angiogenesis

BACKGROUND

Antiphospholipid syndrome (APS) is an autoimmune disease characterized by thrombotic events and/or pregnancy morbidity (≥3 recurrent early miscarriage or fetal death or a prematurity <34 weeks of gestation) with persistently positive antiphospholipid antibodies (aPLs). It is reported that aPLs damage the placental tissue by binding to β2-glycoprotein I (β2GPI) on the surface of trophoblast and endothelial cells. Hydroxychloroquine (HCQ) is considered to be beneficial in the treatment of obstetrical APS and shown to restore the aPL-inhibited invasion and differentiation of trophoblast. However, not enough evidence exists regarding the effect of HCQ on endometrial angiogenesis. The aim of our study was to assess whether HCQ has an effect on aPL-inhibited endothelial angiogenesis.

METHODS

In this research, to explore the effect of HCQ for angiogenesis, we investigated: (1) Human umbilical vein endothelial cells (HUVECs) viability by CCK-8; (2) HUVECs migration by wound healing; (3) HUVEC angiogenesis by Matrigel assay in vitro; (4) mRNA expression of MMP-2 and VEGF by real-time quantitative Polymerase Chain Reaction (RT-PCR); (5) protein expression of VEGF, MMP-2 by western blot.

RESULTS

We found that HCQ treatment significantly restored the expression of aPL-inhibited VEGF and MMP-2. HCQ restored aPL-inhibited HUVEC proliferation, migration, and angiogenesis in vitro.

CONCLUSION

In conclusion, aPLs inhibit HUVECs angiogenesis, however, HCQ can restore the effect of aPL-inhibited HUVECs migration and angiogenesis in vitro, demonstrating its beneficial therapeutic role in obstetrical APS.

Treatment Update in Systemic Lupus Erythematous

The recent updates on treatment recommendations for the management of systemic lupus erythematous have provided greater clarity in the way existing anti-inflammatory and immunomodulatory drugs are used, in treating disease activity, preventing flares, and reducing irreversible organ damage and toxicity arising from the treatments themselves. Novel therapies will provide more options in the armamentarium for treating this complex disease, but ongoing studies are needed to improve understanding of the optimal treatment algorithm to maintain quality of life and improve survival for patients.

The additional use of hydroxychloroquine can improve the live birth rate in pregnant women with persistent positive antiphospholipid antibodies: A systematic review and meta-analysis

PURPOSE

To evaluate the efficacy of additional treatment with hydroxychloroquine (HCQ) for pregnant women with persistent positive antiphospholipid antibodies or antiphospholipid antibody syndrome (APS).

METHOD

We conducted a systematic search of the PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials databases from inception to 31th December 2019. Two authors performed study selection, data collection, and data analysis independently.

RESULT

Five retrospective studies involving 477 pregnancies were selected. The live birth rate was significantly improved in the experimental group (OR, 3.29; 95 % CI, 1.45-7.49; P = 0.004). Additionally, pregnancy loss was associated with the additional use of HCQ (OR, 0.30;95 % CI, 0.13-0.69; P = 0.004). However, HCQ had no significant association with preterm delivery (OR, 0.43; 95 % CI, 0.13-1.37; P = 0.16) and fetal growth restriction showed an OR of 0.22 (95 % CI, 0.13-1.88; P = 0.55).

CONCLUSION

These data suggest that receiving HCQ as an additional treatment can improve the live birth rate in pregnant women with persistent antiphospholipid antibodies.

Zika Virus-Infected Decidual Cells Elicit a Gestational Age-Dependent Innate Immune Response and Exaggerate Trophoblast Zika Permissiveness: Implication for Vertical Transmission

Vertical transmission of the Zika virus (ZIKV) causes severe fetal defects, but the exact pathogenic mechanism is unclear. We identified up to a 10,480-fold higher expression of viral attachment factors AXL, GAS6, and PROS1 and a 3880-fold increase in ZIKV infectiousness/propagation in human term decidual stromal cells versus trophoblasts. Moreover, levels of viral attachment factors and ZIKV are significantly increased, whereas expression of innate immune response genes are significantly decreased, in human first trimester versus term decidual cells. ZIKV-infected decidual cell supernatants increased cytotrophoblasts infection up to 252-fold compared with directly infected cytotrophoblasts. Tizoxanide treatment efficiently inhibited Zika infection in both maternal and fetal cells. We conclude that ZIKV permissiveness, as well as innate immune responsiveness of human decidual cells, are gestational age dependent, and decidual cells augment ZIKV infection of primary human cytotrophoblast cultures, which are otherwise ZIKV resistant. Human decidual cells may act as reservoirs for trimester-dependent placental transmission of ZIKV, accounting for the higher Zika infection susceptibility and more severe fetal sequelae observed in early versus late pregnancy. Moreover, tizoxanide is a promising agent in preventing perinatal Zika transmission as well as other RNA viruses such as coronavirus.

16th International Congress on Antiphospholipid Antibodies Task Force Report on Obstetric Antiphospholipid Syndrome

Obstetric antiphospholipid syndrome (APS) remains a clinical challenge for practitioners, with several controversial points that have not been answered so far. This Obstetric APS Task Force met on the 16th International Congress on Antiphospholipid Antibodies in Manchester, England, to discuss about treatment, diagnostic and clinical aspects of the disease. This report will address evidence-based medicine related to obstetric APS, including limitations on our current management, the relationship between antibodies against domain 1 of β2GPI and obstetric morbidity, hydroxychloroquine use in patients with obstetric APS and factors associated with thrombosis after obstetric APS. Finally, future directions for better understanding this complex condition are also reported by the Task Force coordinators.

Recommendations of the Spanish Rheumatology Society for Primary Antiphospholipid Syndrome. Part II: Obstetric Antiphospholipid Syndrome and Special Situations

OBJECTIVE

The difficulty in diagnosis and the spectrum of clinical manifestations that can determine the choice of treatment for antiphospholipid syndrome (APS) has fostered the development of recommendations by the Spanish Society of Rheumatology (SER), based on the best possible evidence. These recommendations can serve as a reference for rheumatologists and other specialists involved in the management of APS.

METHODS

A panel of 4rheumatologists, a gynaecologist and a haematologist with expertise in APS was created, previously selected by the SER through an open call or based on professional merits. The stages of the work were: identification of the key areas for the document elaboration, analysis and synthesis of the scientific evidence (using the Scottish Intercollegiate Guidelines Network, SIGN levels of evidence) and formulation of recommendations based on this evidence and formal assessment or reasoned judgement techniques (consensus techniques).

RESULTS

Forty-six recommendations were drawn up, addressing 5main areas: diagnosis and evaluation, measurement of primary thromboprophylaxis, treatment for APS or secondary thromboprophylaxis, treatment for obstetric APS and special situations. These recommendations also include the role of novel oral anticoagulants, the problem of recurrences or the key risk factors identified in these subjects. This document reflects the last 25, referring to the areas of: obstetric APS and special situations. The document provides a table of recommendations and treatment algorithms.

CONCLUSIONS

Update of SER recommendations on APS is presented. This document corresponds to part II, related to obstetric SAF and special situations. These recommendations are considered tools for decision-making for clinicians, taking into consideration both the decision of the physician experienced in APS and the patient. A part I has also been prepared, which addresses aspects related to diagnosis, evaluation and treatment.

Complementemia in pregnancies with antiphospholipid syndrome

Prognosis of pregnancies in women with antiphospholipid syndrome has dramatically improved over the past two decades using conventional treatment with low molecular weight heparin and low-dose aspirin. However, despite this regimen, 10-15% of antiphospholipid syndrome patients experience pregnancy losses. Several studies have been performed in order to identify risk factors predictive of complications. Thrombosis has been generally accepted as the key pathogenetic mechanism underlying pregnancy morbidity. However, the thrombogenic state alone is not able to explain all the different mechanisms leading to pregnancy failure. In fact, emerging evidence shows that complement pathway could play an important role in mediating clinical events in antiphospholipid syndrome. However, the exact mechanism through which complement mediates antiphospholipid syndrome complications remains unknown. Low complement levels (C3 and C4) are associated with poor pregnancy outcome in women with antiphospholipid syndrome in different studies. Hypocomplementemia could be indicated as an early predictor of adverse pregnancy outcome, available at the beginning of pregnancy for starting, if necessary, additional treatment to conventional therapy. However, future studies need to better understand the impact of low complement level on antiphospholipid syndrome pregnancy outcome.

Effects of hydroxychloroquine on the human placenta-Findings from in vitro experimental data and a systematic review

Hydroxychloroquine (HCQ), a toll like receptor (TLR) 7 and 9 antagonist, is used during pregnancy for inflammatory conditions with limited understanding of its placental toxicology. We hypothesized that HCQ does not have toxic effects on the placenta and can modulate cytokine release in response to TLR7/9 activation. A systematic review was conducted and no studies of HCQ on multicellular human placental tissue were identified. Accordingly, placental villous explants were cultured for 7 days with HCQ +/- TLR7/9 agonists. HCQ did not affect cell turnover, nutrient transport or cytokine release but increased IL-10 (anti-inflammatory) secretion and promoted syncytiotrophoblast regeneration. Cytokine release stimulated by TLR7/9 agonists was unaffected by HCQ. In conclusion, HCQ did not adversely affect placental tissue and may have a protective anti-inflammatory function. Further research is needed to determine the mechanisms of HCQ actions on human placenta and whether they could be utilized to improve pregnancy outcomes.

HIBISCUS: Hydroxychloroquine for the secondary prevention of thrombotic and obstetrical events in primary antiphospholipid syndrome

The relapse rate in antiphospholipid syndrome (APS) remains high, i.e. around 20%-21% at 5 years in thrombotic APS and 20-28% in obstetrical APS [2, 3]. Hydroxychloroquine (HCQ) appears as an additional therapy, as it possesses immunomodulatory and anti-thrombotic various effects [4-16]. Our group recently obtained the orphan designation of HCQ in antiphospholipid syndrome by the European Medicine Agency. Furthermore, the leaders of the project made the proposal of an international project, HIBISCUS, about the use of Hydroxychloroquine in secondary prevention of obstetrical and thrombotic events in primary APS. This study has been launched in several countries and at now, 53 centers from 16 countries participate to this international trial. This trial consists in two parts: a retrospective and a prospective study. The French part of the trial in thrombosis has been granted by the French Minister of Health in December 2015 (the academic trial independent of the pharmaceutical industry PHRC N PAPIRUS) and is coordinated by one of the members of the leading consortium of HIBISCUS.

Reimagining the antiphospholipid syndrome, an enigmatic thrombophilic disorder, through the looking glass of microscopic imaging

The antiphospholipid syndrome (APS) is an autoimmune thrombophilic disorder that was described as a diagnostic entity over 30 years ago. And yet the pathogenic mechanisms that are responsible for its clinical manifestations remain to be definitively established. The syndrome is defined by (1) the concurrence of vascular thrombosis and/or pregnancy complications together with (2) positivity for immunoassays and coagulation tests that were derived from clinical observations of two anomalous laboratory test results-specifically, false positivity for syphilis infection in uninfected individuals and the finding of inhibitors of blood coagulation in patients who lacked any bleeding tendencies. Over the years, these were standardized into immunoassays and coagulation assays for APS. Here, we describe how prior knowledge of the immunologic and coagulation aspects of the disorder led to research involving a range of imaging modalities including light microscopy, immunohistochemistry, confocal scanning laser microscopy, transmission and scanning electron microscopy, and atomic force microscopy. In turn, the results from those studies led to a "reimagining" of APS that has advanced the understanding of pathogenic mechanisms of the disorder and has led to the development of novel mechanistically based diagnostics along with potential new treatment approaches that target disease mechanisms.

Obstetric Anti-phospholipid Syndrome: State of the Art

PURPOSE OF REVIEW

This review focuses on new pathogenesis and clinical-therapeutic aspects of obstetric anti-phospholipid syndrome (ob-APS) in the last 5 years.

RECENT FINDINGS

The pathogenesis of ob-APS is multifactorial, including placental infarctions, infiltration of inflammatory cells that cause acute and chronic inflammation, leading to uncontrolled inflammation and poor pregnancy outcomes. A preconception counseling and a patient-tailored treatment are fundamental to improve maternal and fetal outcomes. Thanks to conventional treatment, based on low-dose aspirin and heparin, 70% of women with ob-APS can have successful pregnancies. Women with positive anti-phospholipid antibodies (aPL) without clinical manifestations ("aPL carriers") or with obstetric manifestation not fulfilling ob-APS criteria need to be further investigated in order to assess their best management. Great interest has been given to drugs that could interact in the pathophysiological mechanisms, such as hydroxychloroquine, statins, and eculizumab. These drugs could be considered for patients refractory to conventional therapy.

Treatment of antiphospholipid syndrome beyond anticoagulation

Antiphospholipid syndrome (APS) is a systemic autoimmune disorder marked by thrombosis and/or pregnancy morbidity in the presence of antiphospholipid antibodies (aPL). At the present time, treatment is primarily focused on anticoagulation. However, there is increasing awareness of the mechanisms involved in APS pathogenesis, which has led to the trial of novel therapies targeting those mechanisms. Following a brief review of the etiopathogenesis of and current management strategies in APS, this paper focuses on the evidence for these potential, targeted APS treatments, e.g., hydroxychloroquine, statins, rituximab, belimumab, eculizumab, defibrotide, sirolimus, and peptide therapy.

The treatment of anti-phospholipid syndrome: A comprehensive clinical approach

Anti-phospholipid syndrome (APS) is an acquired pro-thrombotic autoimmune disease that predisposes to thrombotic events and/or obstetric complications, in the persistent presence of anti-phospholipid antibodies (aPL). Life long moderate-intensity anticoagulation is the option of choice for aPL-positive patients with a previous thrombosis; critical issues concern the management of those with a history of arterial event due to the high rate of recurrence. Alternatives comprise anti-platelet agents and high-intensity anticoagulation. Low dose aspirin (LDASA) and low molecular weight heparin provide the mainstay of the treatment of obstetric APS, allowing a birth rate in 70% of cases. The management of refractory APS, thrombotic as well as obstetric, is highly debated, but an increasing burden of evidence points towards the beneficial effects of multiple treatments. Similarly, a management envisaging multiple drugs (anticoagulation, steroids, plasma exchange and/or intravenous immunoglobulins) is the most effective approach in catastrophic APS. Asymptomatic aPL carriers are at higher risk of thrombotic and obstetric complications compared to the general population, thus potentially benefitting of a pharmacological intervention. LDASA and hydroxychloroquine can be considered as options, in particular in case of high risk aPL profile, concomitant cardiovascular risk factors or associated autoimmune disease. APS is apparently a simple condition, but its multifaceted nature requires a complex and tailored treatment.

Catastrophic Antiphospholipid Syndrome: Candidate Therapies for a Potentially Lethal Disease

Catastrophic antiphospholipid syndrome (CAPS) is a potentially lethal disease that presents with rapidly progressive multiple organ thromboses. Anticoagulation, corticosteroids, intravenous immunoglobulin, and plasma exchange are the most commonly used treatments for CAPS patients. However, the high mortality despite these medications necessitates new treatment strategies. Following a brief review of current diagnostic and management strategies, we discuss the candidate therapies, i.e., hydroxychloroquine, rituximab, eculizumab, sirolimus, and defibrotide, that can be considered in CAPS patients refractory to traditional treatment.

The effect of hydroxychloroquine on haemostasis, complement, inflammation and angiogenesis in patients with antiphospholipid antibodies

Objectives

HCQ has been described as having a beneficial effect in patients with APS but its mechanism of action is unclear. We hypothesized that HCQ may have effects on subnormal angiogenesis, inflammation and haemostatic biomarkers seen in APS. The aim of our study was to assess laboratory markers [annexin A5 (AnxA5) anticoagulant activity, tissue factor (TF) levels, thromboelastography (TEG), CRP, Bb, C3a and VEGF] in HCQ-naïve patients with aPL at baseline and after commencing HCQ.

Methods

Twenty-two patients with aPL [20 female, 2 male, median age 55 (range 18-70) years] had blood taken pre- and 3 months after starting HCQ 200 mg daily.

Results

Soluble TF levels were significantly reduced comparing baseline and 3 months after HCQ commencement [401.8 (152.8) vs 300.9 (108) pg/ml (P = 0.010)]. No significant changes were found in the following [reported as pre- and post-HCQ commencement, mean (s.d.)]: AnxA5 anticoagulant ratio [187.1 (29.5) vs 193 (31) (P = 0.157)], anti-domain1 β2 glycoprotein1 IgG activity [1.8 (2) vs 1.2 (1.4) μg/ml (P = 0.105)], complement C3a-des-Arg [147.8 (84.5) vs 154.4 (88.1) ng/ml (P = 0.905)], complement Bb [1.3 (0.7) vs 1.1 (0.7) μg/ml (P = 0.422)], VEGF [68.8 (40) vs 59.4 (19.6) pg/ml (P = 0.454)] and CRP [7 (3.5) vs 7 (3.9) μg/ml (P = 0.917)]. TEG results including TEG reaction time, achievement of clot firmness, TEG maximum amplitude and TEG percentage lysis 30 and 60 min after maximum amplitude showed no significant difference.

Conclusion

HCQ significantly reduced soluble TF levels in patients with aPL. No significant change was observed in AnxA5 activity, anti-domain 1 IgG activity, TEG, CRP, complement Bb and C3a-des-Arg, and VEGF. Further studies of a larger patient cohort are needed.

Diagnosis and management of the antiphospholipid syndrome

Antiphospholipid syndrome (APS) is characterized by thrombosis and/or pregnancy complications in the presence of persistent antiphospholipid antibodies (APLA). Laboratory diagnosis of APLA depends upon the detection of a lupus anticoagulant, which prolongs phospholipid-dependent anticoagulation tests, and/or anticardiolipin (aCL) and anti-β2-glycoprotein-1 (β2GPI) antibodies. APLA are primarily directed toward phospholipid binding proteins. Pathophysiologic mechanisms underlying thrombosis and pregnancy loss in APS include APLA induced cellular activation, inhibition of natural anticoagulant and fibrinolytic systems, and complement activation, among others. There is a high rate of recurrent thrombosis in APS, especially in triple positive patients (patients with lupus anticoagulant, aCL and anti-β2GPI antibodies), and indefinite anticoagulation with a vitamin K antagonist is the standard of care for thrombotic APS. There is currently insufficient evidence to recommend the routine use of direct oral anticoagulants (DOAC) in thrombotic APS. Aspirin with low molecular weight or unfractionated heparin may reduce the incidence of pregnancy loss in obstetric APS. Recent insights into the pathogenesis of APS have led to the identification of new potential therapeutic interventions, including anti-inflammatory and immunomodulatory therapies. Additional research is needed to better understand the effects of APLA on activation of signaling pathways in vascular cells, to identify more predictive biomarkers that define patients at greatest risk for a first or recurrent APLA-related clinical event, and to determine the safety and efficacy of DOACs and novel anti-inflammatory and immune-modulatory therapies for refractory APS.

Recent advances in understanding antiphospholipid syndrome

Antiphospholipid syndrome (APS), also known as Hughes Syndrome, is a systemic autoimmune disease characterized by thrombosis and/or pregnancy morbidity in the presence of persistently positive antiphospholipid antibodies. A patient with APS must meet at least one of two clinical criteria (vascular thrombosis or complications of pregnancy) and at least one of two laboratory criteria including the persistent presence of lupus anticoagulant (LA), anticardiolipin antibodies (aCL), and/or anti-b2 glycoprotein I (anti-b2GPI) antibodies of IgG or IgM isotype at medium to high titres in patient’s plasma. However, several other autoantibodies targeting other coagulation cascade proteins (i.e. prothrombin) or their complex with phospholipids (i.e. phosphatidylserine/prothrombin complex), or to some domains of β2GPI, have been proposed to be also relevant to APS. In fact, the value of testing for new aPL specificities in the identification of APS in thrombosis and/or pregnancy morbidity patients is currently being investigated.

Emerging Therapies in Antiphospholipid Syndrome

Antiphospholipid syndrome (APS) is a hypercoagulable state characterized by arterial and venous thromboses and pregnancy morbidity in the presence of antiphospholipid antibodies. Although warfarin remains the main therapeutic choice in APS, there is still concern about its efficacy, safety, and patient compliance. Patients with refractory APS to conventional therapy as well as patients with non-classical manifestations of APS may have alternative treatment approaches. APS pathogenesis has been further elucidated over the past years identifying new molecules as potential new treatment targets. This review summarizes available data from in vitro and animal models and clinical studies on the role of new potential treatment approaches including new oral anticoagulants and immunoregulatory agents: direct thrombin or factor Xa inhibitors, hydroxychloroquine, statins, B cell inhibition, complement inhibition, peptide therapy, nuclear factor κB and p38 mitogen-activated kinase inhibitors, defibrotide, abciximab, mTOR inhibitor, and other potential targets. Large multicenter prospective studies of well-characterized APS patients are needed to assess the efficacy and safety profile of these potential treatment alternatives.

Complement inhibition by hydroxychloroquine prevents placental and fetal brain abnormalities in antiphospholipid syndrome

Placental ischemic disease and adverse pregnancy outcomes are frequently observed in patients with antiphospholipid syndrome (APS). Despite the administration of conventional antithrombotic treatment a significant number of women continue to experience adverse pregnancy outcomes, with uncertain prevention and management. Efforts to develop effective pharmacological strategies for refractory obstetric APS cases will be of significant clinical benefit for both mothers and fetuses. Although the antimalarial drug, hydroxychloroquine (HCQ) is increasingly used to treat pregnant women with APS, little is known about its efficacy and mechanism of action of HCQ. Because complement activation plays a crucial and causative role in placental ischemia and abnormal fetal brain development in APS we hypothesised that HCQ prevents these pregnancy complications through inhibition of complement activation. Using a mouse model of obstetric APS that closely resembles the clinical condition, we found that HCQ prevented fetal death and the placental metabolic changes -measured by proton magnetic resonance spectroscopy in APS-mice. Using 111In labelled antiphospholipid antibodies (aPL) we identified the placenta and the fetal brain as the main organ targets in APS-mice. Using this same method, we found that HCQ does not inhibit aPL binding to tissues as was previously suggested from in vitro studies. While HCQ did not affect aPL binding to fetal brain it prevented fetal brain abnormal cortical development. HCQ prevented complement activation in vivo and in vitro. Complement C5a levels in serum samples from APS patients and APS-mice were lower after treatment with HCQ while the antibodies titres remained unchanged. HCQ prevented not only placental insufficiency but also abnormal fetal brain development in APS. By inhibiting complement activation, HCQ might also be an effective antithrombotic therapy.

Immunity and early atherosclerosis in the course of systemic lupus erythematosus, mixed connective tissue disease and antiphospholipid syndrome

Atherosclerosis is a chronic inflammatory disease of the arteries associated with various risk factors that promote lipid abnormalities, development and progression of atherosclerotic lesions, plaque rupture, and vascular thrombosis. Atherosclerosis is accelerated in autoimmune diseases. Non-invasive investigations showed increased intima-media thickness (IMT), carotid plaque, and coronary artery calcifications in patients with antiphospholipid syndrome, systemic lupus erythematosus and mixed connective tissue disease compared to controls. The balance between the proinflammatory and anti-inflammatory cytokines allows the immune equilibrium to be maintained. In autoimmune diseases the prevalence of proinflammatory factors leads to premature atherosclerosis. This review presents complementary knowledge on innate and adaptive immunity, cytokines and the role of inflammasomes in progression of early atherosclerosis.

Reproductive outcomes following hydroxychloroquine use for autoimmune diseases: a systematic review and meta-analysis

AIMS

The objective of this meta-analysis was to determine whether gestational use of hydroxychloroquine (HCQ) for autoimmune disorders leads to an increase in the risk for adverse pregnancy outcomes.

METHODS

MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials databases were searched from inception to November 21 2014. Studies which reported the outcomes of pregnant women after exposure to HCQ during pregnancy and including a control (unexposed) group were included. Two independent reviewers carried out the review and the quality assessment using the Methodological Index for Non-Randomized Studies (MINORS). A random effects method was used to calculate the odds ratios (OR) for the outcomes.

RESULTS

The meta-analysis reported no significant increases in rates of major congenital (OR 1.13, 95% confidence interval (CI) 0.59, 2.17), craniofacial (OR 0.62, 95% CI 0.13, 3.03), cardiovascular (OR 1.06, 95% CI 0.29, 3.86), genitourinary (OR 1.38, 95% CI 0.42, 4.53), nervous system malformations (OR 1.81, 95% CI 0.31, 10.52), stillbirth (OR 0.69, 95% CI 0.35, 1.34), low birth weight (OR 0.69, 95% CI 0.21, 2.27) or prematurity (OR 1.75, 95% CI 0.95, 3.24). The rate of spontaneous abortions, however, was found to be significantly increased in HCQ exposed pregnancies (OR 1.85, 95% CI 1.10, 3.13). No significant heterogeneity was detected among the studies for the evaluated outcomes except prematurity.

CONCLUSIONS

Prenatal exposure to HCQ for autoimmune diseases does not appear to increase the risk of adverse pregnancy outcomes except spontaneous abortion rate, which may be associated with the underlying disease activity (bias by indication) and needs further investigation.

The impact of hydroxychloroquine treatment on pregnancy outcome in women with antiphospholipid antibodies

BACKGROUND

Antiphospholipid syndrome is defined by the combination of thrombotic events and/or obstetric morbidity in patients who have tested positive persistently for antiphospholipid antibodies. With good treatment, approximately 70% of pregnant women with antiphospholipid syndrome will deliver a viable live infant. However, current management does not prevent all maternal, fetal, and neonatal complications of antiphospholipid syndrome.

OBJECTIVES

This observational, retrospective, single-center cohort study aimed to assess pregnancy outcome in women with antiphospholipid antibodies who were treated with hydroxychloroquine in addition to conventional treatment during pregnancy.

STUDY DESIGN

One-hundred seventy pregnancies in 96 women with persistent antiphospholipid antibodies were analyzed: (1) 51 pregnancies that occurred in 31 women were treated with hydroxychloroquine for at least 6 months before pregnancy, and the therapy continued throughout gestation (group A); (2) 119 pregnancies that occurred in 65 women with antiphospholipid antibodies that were not treated with hydroxychloroquine were included as controls (group B).

RESULTS

Hydroxychloroquine-treatment was associated with a higher rate of live births (67% group A vs 57% group B; P = .05) and a lower prevalence of antiphospholipid antibodies-related pregnancy morbidity (47% group A vs 63% B; P = .004). The association of hydroxychloroquine with a lower rate of any complication in pregnancy was confirmed after multivariate analysis (odds ratio, 2.2; 95% confidence interval, 1.2-136; P = .04). Fetal losses at >10 weeks of gestation (2% vs 11%; P = .05) and placenta-mediated complications (2% vs 11%; P = .05) were less frequent in group A than group B. Pregnancy duration was longer in group A than group B (27.6 [6-40] vs 21.5 [6-40] weeks; P = .03). There was a higher rate of spontaneous vaginal labor in hydroxychloroquine-treated women compared with group B (37.3% vs 14.3%; P = .01).

CONCLUSIONS

Despite the heterogeneity in the 2 groups in terms of systemic lupus erythematosus prevalence and previous pregnancy history, our results support the concept that women with antiphospholipid antibodies may benefit from treatment with hydroxychloroquine during pregnancy to improve pregnancy outcome. The addition of hydroxychloroquine to conventional treatment is worthy of further assessment in a proper designed randomized controlled trial.

Antiphospholipid syndrome: an update

BACKGROUND

Antiphospholipid syndrome (APS) or 'Hughes syndrome' is a prothrombotic disease characterized by thrombosis and pregnancy morbidity in the presence of antiphospholipid antibodies (aPL). More than three decades have passed, and experts are still uncovering new pieces of this disease complex pathogenesis and management.

MATERIALS AND METHODS

We searched in literature using MEDLINE and PubMed databases focusing on the latest development on disease pathogenesis, risk assessment of thrombosis and treatment of APS.

RESULTS

The phosphatidylinositol 3-kinase (PI3K)-AKT-mTORC pathway was most recently identified to have a crucial role in activating inflammation among endothelial vessel wall causing vascular lesions in APS. Additionally, new variables are being implemented to assess the risk of thrombosis in patients with APS. Global APS Score (GAPSS) utilizes cardiovascular risk factors and new autoimmune antibodies as part of the score assessment and is the most valid so far. It can be a promising tool in the future for prediction of thrombosis. Anticoagulation remains the cornerstone in APS; however, many new potential therapeutic agents are developing and are currently under investigation.

CONCLUSIONS

The most recent advances in pathogenesis, risk stratification and treatment provide a platform for high yield studies with the ultimate goal of providing the optimal management to patients with APS.

Is there any role for the hydroxychloroquine (HCQ) in refractory obstetrical antiphospholipid syndrome (APS) treatment?

The best therapy regimen for refractory obstetrical antiphospholipid syndrome remains to be determined. Additional treatments with steroids, plasma exchanges and immunoglobulins failed to show any beneficial effect. We present a case of a woman who had a better pregnancy outcome after the administration of hydroxychloroquine (HCQ) as additional treatment. Furthermore, we highlighted that HCQ was able to dramatically reduce the antiphospholipid antibodies levels.

The efficacy of hydroxychloroquine for obstetrical outcome in anti-phospholipid syndrome: Data from a European multicenter retrospective study

In European multicenter study, we aimed to describe the real-life hydroxychloroquine use in APS patients during pregnancy and determine its benefit in refractory obstetrical APS. We analyzed the outcome of pregnancies treated by hydroxychloroquine in patients with APS or asymptomatic antiphospholipid (aPL) antibodies carriers. Thirty patients with APS with 35 pregnancies treated by hydroxychloroquine were analyzed. Comparing the outcome of pregnancies treated by the addition of hydroxychloroquine to previous pregnancies under the conventional treatment, pregnancy losses decreased from 81% to 19% (p<0.05), without differences in the associated treatments. The univariate analysis showed that the previous intrauterine deaths and higher hydroxychloroquine amount (400mg per day) were the factors associated with pregnancy outcome. Considering 14 patients with previous refractory obstetrical APS (n=5 with obstetrical and thrombotic primary APS and n=9 with purely obstetrical APS), all with previous pregnancy losses under treatment (aspirin with LMWH in 11 cases and LMWH in 3 cases), the addition of hydroxychloroquine resulted in live born babies in 11/14 (78%) cases (p<0.05). Our study shows the benefit of hydroxychloroquine addition in patients with refractory obstetrical APS and raises the need of prospective studies to confirm our preliminary study.

The antiphospholipid syndrome: still an enigma

Antiphospholipid syndrome (APS) is defined by clinical manifestations that include thrombosis and/or fetal loss or pregnancy morbidity in patients with antiphospholipid antibodies (aPL). Antiphospholipid antibodies are among the most common causes of acquired thrombophilia, but unlike most of the genetic thrombophilias are associated with both venous and arterial thrombosis. Despite an abundance of clinical and basic research on aPL, a unified mechanism that explains their prothrombotic activity has not been defined; this may reflect the heterogeneity of aPL and/or the fact that they may influence multiple pro- and/or antithrombotic pathways. Antiphospholipid antibodies are directed primarily toward phospholipid binding proteins rather than phospholipid per se, with the most common antigenic target being β2-glycoprotein 1 (β2GPI) although antibodies against other targets such as prothrombin are well described. Laboratory diagnosis of aPL depends upon the detection of a lupus anticoagulant (LA), which prolongs phospholipid-dependent anticoagulation tests, and/or anticardiolipin and anti-β2-glycoprotein 1 antibodies. Indefinite anticoagulation remains the mainstay of therapy for thrombotic APS, although new strategies that may improve outcomes are emerging. Preliminary reports suggest caution in the use of direct oral anticoagulants in patients with APS-associated thrombosis. Based on somewhat limited evidence, aspirin and low molecular weight heparin are recommended for obstetrical APS. There remains a pressing need for better understanding of the pathogenesis of APS in humans, for identification of clinical and laboratory parameters that define patients at greatest risk for APS-related events, and for targeted treatment of this common yet enigmatic disorder.

Antiphospholipid antibodies and the placenta: a systematic review of their in vitro effects and modulation by treatment

BACKGROUND

Antiphospholipid antibodies (aPL) are a family of auto-antibodies that are associated with an increased risk of recurrent miscarriage, intrauterine growth restriction and preterm birth. The placenta is a major target of aPL and it is likely that these antibodies promote pregnancy morbidity by affecting trophoblast function. Numerous studies have investigated the effect of aPL on trophoblast function in vitro. However, different trophoblast models and a variety of culture conditions have been employed, resulting in a myriad of different reported findings. This review systematically summarized those published studies that have investigated the effect of aPL on trophoblast function in vitro. In addition, the reported effects of pharmacological treatment on trophoblast function in the presence of aPL were also systematically reviewed.

METHODS

PubMed, Scopus, Embase and Web of Science databases were searched using the keywords 'placenta OR trophoblast' AND 'antiphospholipid antibody OR antiphospholipid syndrome' up to 25 April 2014. Studies were excluded based on the absence of appropriate controls. The effects of aPL on trophoblast proliferation, death, syncytialization, invasion, hormone production, cytokine production, coagulation and complement activation were recorded. The effects of different treatments on the function of trophoblasts in the presence of aPL were also recorded.

RESULTS

A total of 1071 records were retrieved from the four databases. After removing duplicates, the titles and abstracts of 529 articles were reviewed. Of those, 48 articles were read and relevant experimental results were extracted from 47 articles.

CONCLUSIONS

This systematic review provides an overview of all the studies performed to date on the effects of aPL on trophoblast function in vitro. There is considerable support for aPL decreasing trophoblast viability, syncytialization and invasion in vitro. Some work has also suggested that aPL may affect the production of hormones and signalling molecules by trophoblasts, and may stimulate coagulation and complement activation in vitro. Current reports of the in vitro effects of therapeutic treatments on trophoblast function in the presence of aPL are inconclusive. This systematic review has highlighted many gaps in our knowledge of how aPL work and may direct future research in this area.

Obstetrical APS: is there a place for hydroxychloroquine to improve the pregnancy outcome?

The use of the conventional APS treatment (the combination of low-dose aspirin and LMWH) dramatically improved the obstetrical prognosis in primary obstetrical APS (OAPS). The persistence of adverse pregnancy outcome raises the need to find other drugs to improve obstetrical outcome. Hydroxychloroquine is widely used in patients with various autoimmune diseases, particularly SLE. Antimalarials have many anti-inflammatory, anti-aggregant and immune-regulatory properties: they inhibit phospholipase activity, stabilize lysosomal membranes, block the production of several pro-inflammatory cytokines and, in addition, impair complement-dependent antigen-antibody reactions. There is ample evidence of protective effects of hydroxychloroquine in OAPS similar to the situation in SLE arising from in vitro studies of pathophysiological working mechanism of hydroxychloroquine. However, the clinical data on the use of hydroxychloroquine in primary APS are lacking and prospective studies are necessary.

A new trick for an ancient drug: quinine dissociates antiphospholipid immune complexes

Quinine, a quinoline derivative, is an ancient antipyretic drug with antimalarial properties that has been phased out by more effective synthetic candidates. In previous studies we discovered that hydroxychloroquine (HCQ), a synthetic antimalarial with structural similarities to quinine, reduced the binding of antiphospholipid (aPL) immune complexes to phospholipid bilayers. We performed ellipsometry and atomic force microscopy (AFM) studies to measure the effect of quinine on dissociation of anti-β2-glycoprotein I (anti-β2GPI) immune complexes. We found that quinine desorbed pre-formed β2GPI-aPL immunoglobulin (Ig)G complexes from phospholipid bilayers at significantly lower molar concentrations than HCQ. Quinine also inhibited the formation of immune complexes with a higher efficacy than HCQ at equivalent drug concentrations of 0.2 mg/ml (0.192 ± 0.025 µg/cm(2) for quinine vs. 0.352 ± 0.014 µg/cm(2) for HCQ, p < 0.001). Furthermore, AFM imaging experiments revealed that addition of quinine disintegrated immune complexes bound to planar phospholipid layers. The desorptive and inhibitory effects of the old drug, quinine, toward β2GPI-aPL IgG complexes and β2GPI were significantly more pronounced compared to the synthetic antimalarial, HCQ. The results suggest that the quinoline core of the molecule is a critical domain for this activity and that side chains may further modulate this effect. The results also indicate that there may yet be room for considering new activities of very old drugs in devising clinical trials on potential non-anticoagulant treatments for antiphospholipid syndrome (APS).

Pregnancy morbidity in antiphospholipid syndrome: what is the impact of treatment?

Women with persistently circulating antiphospholipid antibodies (aPL) have a higher incidence of recurrent abortions, fetal losses, pre-eclampsia, and placental insufficiency. Current treatment of patients with antiphospholipid syndrome (APS) during pregnancy with heparin and aspirin can act by preventing clot formation and improving live birth rates, but other obstetric morbidities remain high, especially in patients with a history of thrombotic events. In addition to the classical thrombotic placental events, other factors involving inflammation and complement activation seem to play a role in certain complications. In this article, we will review how medications interfere in the pathogenic mechanisms of APS, discuss the impact of current recommended treatment on pregnancy morbidity, and analyze new promising therapies.

Hydroxychloroquine restores trophoblast fusion affected by antiphospholipid antibodies

BACKGROUND

Obstetric antiphospholipid syndrome (APS) is defined by pregnancy complications associated with antiphospholipid antibodies (aPL). The mechanisms of the pathogenic effects of aPL in pregnancy are poorly understood. Toll-like receptors (TLR) have been implicated previously in APS.

OBJECTIVES

The aims of our study were (1) to determine aPL effects on trophoblastic cell fusion and differentiation, (2) to identify which TLR is involved in this process, and (3) to evaluate the efficacy of hydroxychloroquine (HCQ) to counteract the effects of aPL.

METHODS

BeWo cells are a model for trophoblast fusion and differentiation. Fusion index was assessed by immunocytochemical examination, and biochemical differentiation by using ELISA-measured β-human choronic gonadotropin hormone (β-hCG) secretion. We used three types of aPL to study their effect on cell fusion and differentiation: aPL derived from obstetric APS patients and affinity purified and polyclonal rabbit anti-β2-glycoprotein-1 (anti-β2GP1) antibodies. Experiments on fusion were confirmed using primary cytotrophoblastic cells.

RESULTS

All of the types of aPL used decreased the fusion index in BeWo and primary trophoblastic cells (64%, 52%, and 41% for BeWo cells and 67% and 62% for primary cells, respectively), and anti-β2GP1 antibodies decreased hCG secretion in BeWo cells (41%). To block TLR4 antibodies or to abolish TLR4 cell surface expression restored fusion index in both cell types and β-human choronic gonadotropin hormone excretion in BeWo cells. HCQ treatment induced the same effect and decreased TLR4 mRNA (40% and 35%, respectively) and protein expressions (62% and 42%, respectively) in BeWo cells.

CONCLUSION

Anti-β2GP1 antibodies decrease trophoblastic differentiation via TLR4. This effect is restored by HCQ, suggesting its therapeutic interest in APS pregnancies.

Effect of hydroxychloroquine on antiphospholipid antibody-induced changes in first trimester trophoblast function

PROBLEM

Women with antiphospholipid syndrome (APS) are at risk for pregnancy complications. Antiphospholipid antibodies (aPL) alter trophoblast function by triggering an inflammatory cytokine response; modulating angiogenic factor secretion; and inhibiting migration. While patients with APS are often treated with hydroxychloroquine (HCQ), its effect on trophoblast function is poorly understood.

METHOD OF STUDY

A human first trimester trophoblast cell line was treated with or without antihuman β2GPI mAbs in the presence or absence of HCQ. Supernatants were analyzed by ELISA. Cell migration was measured using a colormetric assay.

RESULTS

Antiphospholipid antibodies-induced trophoblast IL-8, IL-1 β, PlGF, and sEndoglin secretion were not altered by HCQ. aPL-induced inhibition of trophoblast migration was partially reversed by HCQ, even though HCQ significantly increased secretion of pro-migratory IL-6 to greater than baseline. aPL-induced upregulation of TIMP2 appears to inhibit trophoblast migration; the inability of HCQ to prevent aPL-induced TIMP2 may explain why migration was only partially restored.

CONCLUSION

Hydroxychloroquine reversed the aPL-inhibition of trophoblast IL-6 secretion and partially limited aPL-inhibition of cell migration. Thus, some form of combination therapy that includes HCQ may be beneficial to pregnant APS patients.

[Conventional basis therapy of rheumatoid arthritis. Effects within and outside cells]

Conventional disease-modifying antirheumatic drugs (DMARDs) were formerly introduced into the treatment of rheumatoid arthritis and other rheumatic disorders on an empirical basis. In many cases their mode of action is only partially understood but as a rule of thumb they act on more than one point within the cellular metabolism. Less often they exert biological effects in the extracellular space or on the cell membrane.