Interferon-α and angiogenic dysregulation in pregnant lupus patients who develop preeclampsia

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.

Understanding the Pathophysiology of Preeclampsia: Exploring the Role of Antiphospholipid Antibodies and Future Directions

Preeclampsia (PE) is a hypertensive disorder in pregnancy associated with significant fetal and maternal complications. Antiphospholipid syndrome (APS) is an acquired form of thrombophilia characterized by recurrent venous or arterial thrombosis and obstetric complications that significantly increases morbidity and mortality rates. While preeclampsia may not be the most prevalent obstetric complication in APS, it significantly impacts the long-term health of both mother and child. The treatment of preeclampsia in antiphospholipid syndrome is different from the treatment of preeclampsia as an independent disease. Despite current treatments involving anticoagulants, antiplatelet agents, and antihypertensive drugs, obstetric complications may persist, underscoring the need for cohesive management and effective treatments. The objective of our review is to briefly present knowledge about the physiopathology of preeclampsia and the role of antiphospholipid antibodies in this process. Based on the existing literature, our review aims to identify future directions in molecular pathology toward the discovery of biomarkers and targeted treatments. The application of multidisciplinary approaches and prognostic models, including new biomarkers, could be beneficial in the prediction of PE.

Pregnancy and the Autoimmune Patient

PURPOSE OF REVIEW

This article will review the current understanding of the immunologic changes that occur during pregnancy. It will discuss the impact of pregnancy on the disease activity of autoimmune or inflammatory rheumatic diseases (AIRD). Lastly, it will highlight the most recent data on pre-conception and pregnancy management practices that can improve pregnancy outcomes in autoimmune patients.

RECENT FINDINGS

Pregnancy is an immunologically complex and dynamic state that may affect the activity of AIRDs, with more patients having active disease during pregnancy than previously thought. Uncontrolled inflammatory diseases are associated with poor pregnancy outcomes such as preeclampsia, small for gestational age infants, and prematurity. Pre-conception counseling and early pregnancy planning discussions can help ensure optimal disease control and medication management prior to attempting conception. Adequate control of AIRDs on pregnancy-compatible medications during the pre-conception, pregnancy, and postpartum periods is required for optimal pregnancy outcomes.

Type I interferon alters invasive extravillous trophoblast function

Inappropriate type I interferon (IFN) signaling during embryo implantation and placentation is linked to poor pregnancy outcomes. Here, we evaluated the consequence of elevated type I IFN exposure on implantation using a biomimetic model of human implantation in an organ-on-a-chip device. We found that type I IFN reduced extravillous trophoblast (EVT) invasion capacity. Analyzing single-cell transcriptomes, we uncovered that IFN truncated endovascular EVT emergence in the implantation-on-a-chip device by stunting EVT epithelial-to-mesenchymal transition. Disruptions to the epithelial-to-mesenchymal transition is associated with the pathogenesis of preeclampsia, a life-threatening hypertensive disorder of pregnancy. Strikingly, unwarranted IFN stimulation induced genes associated with increased preeclampsia risk and a preeclamptic gene-like signature in EVTs. These dysregulated EVT phenotypes ultimately reduced EVT-mediated endothelial cell vascular remodeling in the implantation-on-a-chip device. Overall, our work indicates IFN signaling can alter EVT epithelial-to-mesenchymal transition progression which results in diminished EVT-mediated spiral artery remodeling and a preeclampsia gene signature upon sustained stimulation. Our work implicates unwarranted type I IFN as a maternal disturbance that can result in abnormal EVT function that could trigger preeclampsia.

Sex differences in innate and adaptive immunity impact fetal, placental, and maternal health†

The differences between males and females begin shortly after birth, continue throughout prenatal development, and eventually extend into childhood and adult life. Male embryos and fetuses prioritize proliferation and growth, often at the expense of the fetoplacental energy reserves. This singular focus on growth over adaptability leaves male fetuses and neonates vulnerable to adverse outcomes during pregnancy and birth and can have lasting impacts throughout life. Beyond this prioritization of growth, male placentas and fetuses also respond to infection and inflammation differently than female counterparts. Pregnancies carrying female fetuses have a more regulatory immune response, whereas pregnancies carrying male fetuses have a stronger inflammatory response. These differences can be seen as early as the innate immune response with differences in cytokine and chemokine signaling. The sexual dimorphism in immunity then continues into the adaptive immune response with differences in T-cell biology and antibody production and transfer. As it appears that these sex-specific differences are amplified in pathologic pregnancies, it stands to reason that differences in the placental, fetal, and maternal immune responses in pregnancy contribute to increased male perinatal morbidity and mortality. In this review, we will describe the genetic and hormonal contributions to the sexual dimorphism of fetal and placental immunity. We will also discuss current research efforts to describe the sex-specific differences of the maternal-fetal interface and how it impacts fetal and maternal health.

IFITM1 inhibits trophoblast invasion and is induced in placentas associated with IFN-mediated pregnancy diseases

Interferon-induced transmembrane proteins (IFITMs) are restriction factors that block many viruses from entering cells. High levels of type I interferon (IFN) are associated with adverse pregnancy outcomes, and IFITMs have been shown to impair the formation of syncytiotrophoblast. Here, we examine whether IFITMs affect another critical step of placental development, extravillous cytotrophoblast (EVCT) invasion. We conducted experiments using in vitro/ex vivo models of EVCT, mice treated in vivo with the IFN-inducer poly (I:C), and human pathological placental sections. Cells treated with IFN-β demonstrated upregulation of IFITMs and reduced invasive abilities. Transduction experiments confirmed that IFITM1 contributed to the decreased cell invasion. Similarly, migration of trophoblast giant cells, the mouse equivalent of human EVCTs, was significantly reduced in poly (I:C)-treated mice. Finally, analysis of CMV- and bacterial-infected human placentas revealed upregulated IFITM1 expression. These data demonstrate that high levels of IFITM1 impair trophoblast invasion and could explain the placental dysfunctions associated with IFN-mediated disorders.

Correlation of placental lesions in patients with systemic lupus erythematosus, antiphospholipid syndrome and non-criteria obstetric antiphospholipid syndrome and adverse perinatal outcomes

INTRODUCTION

We aimed to describe the pattern of placental injuries in women with systemic lupus erythematosus (SLE), antiphospholipid antibody syndrome (APS) and non-criteria obstetric APS (NC-OAPS), and to correlate the placental findings with the occurrence of adverse perinatal outcomes.

METHODS

The perinatal outcomes and placental findings of pregnancies of women with SLE, APS, and NC-OAPS and gestational-age matched healthy controls were analyzed and classified according to the 2015 Redline - Classification of placental lesions.

RESULTS

91 women with SLE, APS, and NC-OAPS and 91 controls were included. Mean values of placental weight differed between groups, being significantly lower in NC-OAPS and APS groups compared to controls. Furthermore, 14.3% of placentas in the APS group were under the 3rd percentile, which was significantly higher in comparison with other groups. Regarding histopathological placental findings, maternal-side malperfusion was significantly increased in APS (46.4%) compared to NC-OAPS (14.3%) and SLE (9.5%). Fetal-side maldevelopment was significantly increased in NC-OAPS (19.1%) compared to controls (1.1%) and SLE (2.4%). A significantly increased prevalence of adverse perinatal outcomes (APOs) was observed in all studied groups compared to healthy controls (controls 3.3%, SLE 52.4%, NC-OAPS 57.1%, APS 64.3%). Overall, both maternal (OR 6.8, 95%CI 2.1-22) and fetal-side (OR 4.1, 95%CI 1.3-13.5) lesions were significantly associated with APO. Maternal malperfusion and fetal maldevelopment were the lesions most strongly associated with APOs.

DISCUSSION

Pregnant women with SLE, APS, or NC-OAPS showed a different pattern of histopathological findings. Compared to controls, SLE, APS, and NC-OAPS conferred an increased risk of APOs that was strongly associated with placental maternal-side malperfusion and fetal-side maldevelopment.

Pregnancy-associated systemic gene expression compared to a pre-pregnancy baseline, among healthy women with term pregnancies

Background

Pregnancy is known to induce extensive biological changes in the healthy mother. Little is known, however, about what these changes are at the molecular level. We have examined systemic expression changes in protein-coding genes and long non-coding (lnc) RNAs during and after pregnancy, compared to before pregnancy, among healthy women with term pregnancies.

Methods

Blood samples were collected from 14 healthy women enrolled in our prospective pregnancy cohort at 7 time-points (before, during and after pregnancy). Total RNA from frozen whole blood was used for RNA sequencing. Following raw read alignment and assembly, gene-level counts were obtained for protein-coding genes and long non-coding RNAs. At each time-point, cell type proportions were estimated using deconvolution. To examine associations between pregnancy status and gene expression over time, Generalized Estimating Equation (GEE) models were fitted, adjusting for age at conception, and with and without adjusting for changes in cell type proportions. Fold-changes in expression at each trimester were examined relative to the pre-pregnancy baseline.

Results

Numerous immune-related genes demonstrated pregnancy-associated expression, in a time-dependent manner. The genes that demonstrated the largest changes in expression included several that were neutrophil-related (over-expressed) and numerous immunoglobulin genes (under-expressed). Estimated cell proportions revealed a marked increase in neutrophils, and less so of activated CD4 memory T cells, during pregnancy, while most other cell type proportions decreased or remained unchanged. Adjusting for cell type proportions in our model revealed that although most of the expression changes were due to changes in cell type proportions in the bloodstream, transcriptional regulation was also involved, especially in down-regulating expression of type I interferon inducible genes.

Conclusion

Compared to a pre-pregnancy baseline, there were extensive systemic changes in cell type proportions, gene expression and biological pathways associated with different stages of pregnancy and postpartum among healthy women. Some were due to changes in cell type proportions and some due to gene regulation. In addition to providing insight into term pregnancy among healthy women, these findings also provide a "normal" reference for abnormal pregnancies and for autoimmune diseases that improve or worsen during pregnancy, to assess deviations from normal.

Control of lupus activity during pregnancy via the engagement of IgG sialylation: novel crosstalk between IgG sialylation and pDC functions

Immunoglobulin (IgG) glycosylation affects the effector functions of IgG in a myriad of biological processes and has been closely associated with numerous autoimmune diseases, including systemic lupus erythematosus (SLE), thus underlining the pathogenic role of glycosylation aberration in autoimmunity. This study aims to explore the relationship between IgG sialylation patterns and lupus pregnancy. Relative to that in serum samples from the control cohort, IgG sialylation level was aberrantly downregulated in serum samples from the SLE cohort at four stages (from preconception to the third trimester of pregnancy) and was significantly associated with lupus activity and fetal loss during lupus pregnancy. The type I interferon signature of pregnant patients with SLE was negatively correlated with the level of IgG sialylation. The lack of sialylation dampened the ability of IgG to suppress the functions of plasmacytoid dendritic cells (pDCs). RNA-seq analysis further revealed that the expression of genes associated with the spleen tyrosine kinase (SYK) signaling pathway significantly differed between IgG- and deSia-IgG-treated pDCs. This finding was confirmed by the attenuation of the ability to phosphorylate SYK and BLNK in deSia-IgG. Finally, the coculture of pDCs isolated from pregnant patients with SLE with IgG/deSia-IgG demonstrated the sialylation-dependent anti-inflammatory function of IgG. Our findings suggested that IgG influences lupus activity through regulating pDCs function via the modulation of the SYK pathway in a sialic acid-dependent manner.

Type I interferon pathway assays in studies of rheumatic and musculoskeletal diseases: a systematic literature review informing EULAR points to consider

OBJECTIVES

To systematically review the literature for assay methods that aim to evaluate type I interferon (IFN-I) pathway activation and to harmonise-related terminology.

METHODS

Three databases were searched for reports of IFN-I and rheumatic musculoskeletal diseases. Information about the performance metrics of assays measuring IFN-I and measures of truth were extracted and summarised. A EULAR task force panel assessed feasibility and developed consensus terminology.

RESULTS

Of 10 037 abstracts, 276 fulfilled eligibility criteria for data extraction. Some reported more than one technique to measure IFN-I pathway activation. Hence, 276 papers generated data on 412 methods. IFN-I pathway activation was measured using: qPCR (n=121), immunoassays (n=101), microarray (n=69), reporter cell assay (n=38), DNA methylation (n=14), flow cytometry (n=14), cytopathic effect assay (n=11), RNA sequencing (n=9), plaque reduction assay (n=8), Nanostring (n=5), bisulphite sequencing (n=3). Principles of each assay are summarised for content validity. Concurrent validity (correlation with other IFN assays) was presented for n=150/412 assays. Reliability data were variable and provided for 13 assays. Gene expression and immunoassays were considered most feasible. Consensus terminology to define different aspects of IFN-I research and practice was produced.

CONCLUSIONS

Diverse methods have been reported as IFN-I assays and these differ in what elements or aspects of IFN-I pathway activation they measure and how. No 'gold standard' represents the entirety of the IFN pathway, some may not be specific for IFN-I. Data on reliability or comparing assays were limited, and feasibility is a challenge for many assays. Consensus terminology should improve consistency of reporting.

Association between type I interferon pathway activation and clinical outcomes in rheumatic and musculoskeletal diseases: a systematic literature review informing EULAR points to consider

BACKGROUND

Type I interferons (IFN-I) contribute to a broad range of rheumatic and musculoskeletal diseases (RMDs). Compelling evidence suggests that the measurement of IFN-I pathway activation may have clinical value. Although several IFN-I pathway assays have been proposed, the exact clinical applications are unclear. We summarise the evidence on the potential clinical utility of assays measuring IFN-I pathway activation.

METHODS

A systematic literature review was conducted across three databases to evaluate the use of IFN-I assays in diagnosis and monitor disease activity, prognosis, response to treatment and responsiveness to change in several RMDs.

RESULTS

Of 366 screened, 276 studies were selected that reported the use of assays reflecting IFN-I pathway activation for disease diagnosis (n=188), assessment of disease activity (n=122), prognosis (n=20), response to treatment (n=23) and assay responsiveness (n=59). Immunoassays, quantitative PCR (qPCR) and microarrays were reported most frequently, while systemic lupus erythematosus (SLE), rheumatoid arthritis, myositis, systemic sclerosis and primary Sjögren's syndrome were the most studied RMDs. The literature demonstrated significant heterogeneity in techniques, analytical conditions, risk of bias and application in diseases. Inadequate study designs and technical heterogeneity were the main limitations. IFN-I pathway activation was associated with disease activity and flare occurrence in SLE, but their incremental value was uncertain. IFN-I pathway activation may predict response to IFN-I targeting therapies and may predict response to different treatments.

CONCLUSIONS

Evidence indicates potential clinical value of assays measuring IFN-I pathway activation in several RMDs, but assay harmonisation and clinical validation are urged. This review informs the EULAR points to consider for the measurement and reporting of IFN-I pathway assays.

Mouse models of Zika virus transplacental transmission

Seven years after the onset of the Zika virus (ZIKV) epidemic in the Americas, longitudinal studies are beginning to demonstrate that children infected in utero and born without severe birth defects exhibit motor skill deficits at up to 3 years of age. Long term health and socioeconomic impacts of fetal ZIKV infection appear imminent. ZIKV continues to circulate in low levels much as the virus did for decades prior to the 2015 epidemic, and the timing of the ZIKV outbreak is unknown. Thus, in the continued absence of ZIKV vaccines or antivirals, small animal models of ZIKV transplacental transmission have never been more necessary to test antiviral strategies for both mother and fetuses, and to elucidate mechanisms of immunity at the maternal-fetal interface. Here we review the state of ZIKV transplacental transmission models, highlight key unanswered questions, and set goals for the next generation of mouse models.

Early Prediction of Adverse Pregnancy Outcome in Women with Systemic Lupus Erythematosus, Antiphospholipid Syndrome, or Non-Criteria Obstetric Antiphospholipid Syndrome

A prospectively study of pregnant women with systemic lupus erythematosus (SLE), antiphospholipid syndrome, or non-criteria obstetric antiphospholipid syndrome was conducted to describe the characteristics of women followed in a referral unit and to derive a predictive tool for adverse pregnancy outcome (APO). Demographic characteristics, treatments, SLE activity, and flares were recorded. Laboratory data included a complete blood cell count, protein-to-creatinine urinary ratio (Pr/Cr ratio), complement, anti dsDNA, anti-SSA/Ro, anti-SSB/La, and antiphospholipid antibodies status. A stepwise regression was used to identify baseline characteristics available before pregnancy and during the 1st trimester that were most predictive of APO and to create the predictive model. A total of 217 pregnancies were included. One or more APO occurred in 45 (20.7%) women. A baseline model including non-Caucasian ethnicity (OR 2.78; 95% CI [1.16-6.62]), smoking (OR 4.43; 95% CI [1.74-11.29]), pregestational hypertension (OR 16.13; 95% CI [4.06-64.02]), and pregestational corticosteroids treatment OR 2.98; 95% CI [1.30-6.87]) yielded an AUC of 0.78 (95% CI, [0.70-0.86]). Among first-trimester parameters, only Pr/Cr ratio improved the model fit, but the predictive performance was not significantly improved (AUC of 0.78 vs. 0.81; p = 0.16). Better biomarkers need to be developed to efficiently stratify pregnant women with the most common autoimmune diseases.

Evaluation of anifrolumab safety in systemic lupus erythematosus: A meta-analysis and systematic review

Objectives

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease, and type I interferon plays an important role in its pathogenesis. Anifrolumab is a new strategy for the treatment of systemic lupus erythematosus. It could antagonize the activity of all type 1 interferons by binding with type I interferon receptor subunit 1. The aim of our study was to evaluate the safety of anifrolumab in patients with moderate to severe SLE (excluding patients with active severe lupus nephritis or central nervous system lupus).

Methods

Four databases (Embase, Cochrane, PubMed, Web of Science) were systematically searched from inception until December 2021 for randomized controlled trials (RCTs) evaluating the safety of anifrolumab versus placebo in SLE patients. Then, the incidence of adverse events in each study was aggregated using meta-analysis.

Results

A total of 1160 SLE patients from four RCTs were included in the analysis. Serious adverse events were less common in the anifrolumab group than in the placebo group (RR: 0.76, 95% CI: 0.59-0.98, p<0.03). The most common adverse events included upper respiratory tract infection (RR: 1.48, 95% CI: 1.13-1.94, P=0.004), nasopharyngitis (RR: 1.66, 95% CI: 1.25-2.20, P=0.0004), bronchitis (RR: 1.96, 95% CI: 1.32-2.92, P=0.0009), and herpes zoster (RR: 3.40, 95% CI: 1.90-6.07, P<0.0001).

Conclusion

Anifrolumab is considered a well-tolerated option for the treatment of SLE patients with good safety.

Systematic Review Registration

https://inplasy.com, identifier 202230054.

Placental damage in pregnancies with systemic lupus erythematosus: A narrative review

Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease of unknown cause, which mainly affects women of childbearing age, especially between 15 and 55 years of age. During pregnancy, SLE is associated with a high risk of perinatal morbidity and mortality. Among the most frequent complications are spontaneous abortion, fetal death, prematurity, intrauterine Fetal growth restriction (FGR), and preeclampsia (PE). The pathophysiology underlying obstetric mortality and morbidity in SLE is still under investigation, but several studies in recent years have suggested that placental dysfunction may play a crucial role. Understanding this association will contribute to developing therapeutic options and improving patient management thus reducing the occurrence of adverse pregnancy outcomes in this group of women. In this review, we will focus on the relationship between SLE and placental insufficiency leading to adverse pregnancy outcomes.

Pregnancy-related complications in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a systemic autoimmune inflammatory disease that predominantly affects women of childbearing age and results in various adverse pregnancy outcomes (APOs). Pregnancy was formerly discouraged in patients with SLE because of unstable disease activity during the gestation period, increased thrombosis risk, severe organ damage, and inevitable side effects of immunosuppressive agents. Currently, most patients with SLE have successful pregnancies due to preconception counselling, strict monitoring, and improved therapy with minimised complications for both the mother and foetus. Hydroxychloroquine (HCQ) is extensively used and is beneficial for improving pregnancy outcomes. However, pregnant women with SLE have a high-risk of APOs, such as disease flare, preterm birth, intrauterine growth restriction (IUGR), preeclampsia, and pregnancy loss. Better understanding of the changes in maternal immunity and serum biomarkers, as well as their relationships with SLE-related APOs progression, would facilitate the investigation of molecular mechanisms for triggering and ameliorating APOs. Furthermore, it would enable us to explore and develop novel and effective therapeutic strategies to prevent disease activation. Therefore, this review briefly introduces the interaction between pregnancy outcomes and SLE, elucidates pathophysiological and immunological changes during SLE pregnancy. Furthermore, this review systematically expounds on the effective predictors of APOs and the molecular mechanisms underlying the SLE-related APOs to provide a solid foundation for the advanced management of lupus pregnancy.

Interferon Lambda Signals in Maternal Tissues to Exert Protective and Pathogenic Effects in a Gestational Stage-Dependent Manner

Interferon lambda (IFN-λ) (type III IFN) is constitutively secreted from human placental cells in culture and reduces Zika virus (ZIKV) transplacental transmission in mice. However, the roles of IFN-λ during healthy pregnancy and in restricting congenital infection remain unclear. Here, we used mice lacking the IFN-λ receptor (Ifnlr1^-/-) to generate pregnancies lacking either maternal or fetal IFN-λ responsiveness and found that the antiviral effect of IFN-λ resulted from signaling exclusively in maternal tissues. This protective effect depended on gestational stage, as infection earlier in pregnancy (E7 rather than E9) resulted in enhanced transplacental transmission of ZIKV. In Ifnar1^-/- dams, which sustain robust ZIKV infection, maternal IFN-λ signaling caused fetal resorption and intrauterine growth restriction. Pregnancy pathology elicited by poly(I·C) treatment also was mediated by maternal IFN-λ signaling, specifically in maternal leukocytes, and also occurred in a gestational stage-dependent manner. These findings identify an unexpected effect of IFN-λ signaling, specifically in maternal (rather than placental or fetal) tissues, which is distinct from the pathogenic effects of IFN-αβ (type I IFN) during pregnancy. These results highlight the complexity of immune signaling at the maternal-fetal interface, where disparate outcomes can result from signaling at different gestational stages. IMPORTANCE Pregnancy is an immunologically complex situation, which must balance protecting the fetus from maternal pathogens with preventing maternal immune rejection of non-self fetal and placental tissue. Cytokines, such as interferon lambda (IFN-λ), contribute to antiviral immunity at the maternal-fetal interface. We found in a mouse model of congenital Zika virus infection that IFN-λ can have either a protective antiviral effect or cause immune-mediated pathology, depending on the stage of gestation when IFN-λ signaling occurs. Remarkably, both the protective and pathogenic effects of IFN-λ occurred through signaling exclusively in maternal immune cells rather than in fetal or placental tissues or in other maternal cell types, identifying a new role for IFN-λ at the maternal-fetal interface.

Atypical preeclampsia with systemic lupus erythematosus and elevated soluble fms-like tyrosine kinase 1/placental growth factor ratio

While systemic lupus erythematosus is often complicated by preeclampsia, it is difficult to differentiate between its exacerbation and preeclampsia. The soluble fms-like tyrosine kinase 1 (sFlt-1)/placental growth factor (PlGF) ratio is unknown in systemic lupus erythematosus with preeclampsia before 20 weeks of gestation. Three nulliparous women with systemic lupus erythematosus developed preeclampsia at 13, 13, and 17 weeks of gestation with sFlt-1/PlGF ratios of 427, 865, and 525, respectively. Two patients terminated their pregnancies and delivered within 2 weeks, while one experienced intrauterine fetal death 4 weeks after the measurements. Their symptoms gradually improved, and all patients were discharged within 3 months. The sFlt-1/PlGF ratio may be used in the differential diagnosis of preeclampsia and systemic lupus erythematosus exacerbation before 20 weeks of gestation.

Neutrophil Recruitment and Participation in Severe Diseases Caused by Flavivirus Infection

Neutrophils are first-line responders to infections and are recruited to target tissues through the action of chemoattractant molecules, such as chemokines. Neutrophils are crucial for the control of bacterial and fungal infections, but their role in the context of viral infections has been understudied. Flaviviruses are important human viral pathogens transmitted by arthropods. Infection with a flavivirus may result in a variety of complex disease manifestations, including hemorrhagic fever, encephalitis or congenital malformations. Our understanding of flaviviral diseases is incomplete, and so is the role of neutrophils in such diseases. Here we present a comprehensive overview on the participation of neutrophils in severe disease forms evolving from flavivirus infection, focusing on the role of chemokines and their receptors as main drivers of neutrophil function. Neutrophil activation during viral infection was shown to interfere in viral replication through effector functions, but the resulting inflammation is significant and may be detrimental to the host. For congenital infections in humans, neutrophil recruitment mediated by CXCL8 would be catastrophic. Evidence suggests that control of neutrophil recruitment to flavivirus-infected tissues may reduce immunopathology in experimental models and patients, with minimal loss to viral clearance. Further investigation on the roles of neutrophils in flaviviral infections may reveal unappreciated functions of this leukocyte population while increasing our understanding of flaviviral disease pathogenesis in its multiple forms.

Outcomes of pregnancy and associated factors in sub-Saharan African women with systemic lupus erythematosus: a scoping review

Objective

To scope and summarise available literature on the outcomes of pregnancy and associated factors in sub-Saharan African women with SLE.

Methods

Electronic databases and reference lists of retrieved articles were searched to identify relevant studies published from 1 January 2000 to 28 October 2019. Data were combined through narrative synthesis.

Results

We included four studies retrospectively reporting a total of 137 pregnancies in 102 women over a 26-year period. Mean age at conception ranged from 27.2 to 39.9 years. Kidney damage, the predominant organ manifestation before conception, was reported in 43 (42.2%) patients. Ninety-seven (70.8%) pregnancies resulted in 98 live births. SLE flares occurred in 44 (32.2%) pregnancies, mainly skin (20.4%) and renal (18.2%) flares. Major adverse pregnancy outcomes (APOs) were preterm birth 38.8%, low birth weight 29.8%, pregnancy loss 29.2% and pre-eclampsia 24.8%. The main factors associated with APOs were nephritis and SLE flares.

Conclusion

Over two-thirds of pregnancies resulted in live birth in this cohort of sub-Saharan African women with SLE. The main APOs and associated factors described in other parts of the world are also seen in this region, but with high rates of APOs. A large prospective multinational study is warranted for more compelling evidence.

Activated low-density granulocytes in peripheral and intervillous blood and neutrophil inflammation in placentas from SLE pregnancies

OBJECTIVE

Women with SLE face an increased risk of adverse pregnancy outcomes compared with healthy women, but the underlying immunological mechanisms are unknown. Given the recognised association of neutrophil activation with SLE pathogenesis, we examined whether there is increased neutrophil activation and inflammation in blood and placenta in SLE relative to healthy pregnancy.

METHODS

At delivery, peripheral blood, maternal-derived intervillous blood and placentas were collected from 12 SLE and 10 healthy control pregnancies. The proportion of low-density granulocytes (LDGs) and the activation status of LDG and normal-density granulocytes were examined with flow cytometry. The chemokines CXCL8 and CXCL1 were quantified with a cytometric bead-based assay and interferon alpha (IFNα) protein levels with a Simoa method. IFNα-stimulated maternal-derived decidual stromal cells were examined for CXCL8 gene expression with qPCR. A pathologist, blinded to the patient background, examined all placentas.

RESULTS

Women with SLE had significantly higher proportions of LDG in peripheral blood compared with controls (p=0.02), and LDG in both peripheral and intervillous blood were more activated in SLE relative to healthy pregnancies (peripheral blood: p=0.002 and intervillous blood: p=0.05). There were higher levels of CXCL8 and CXCL1 in intervillous compared with peripheral blood in women with SLE (p=0.004 and p=<0.0001, respectively) but not in controls. In SLE pregnancy, IFNα was detectable in 6 out of 10 intervillous blood samples but only in one control. Stimulation with IFNα upregulated CXCL8 gene expression in decidual stromal cells from both SLE and healthy pregnancy. Histological chorioamnionitis was present in 6 out of 12 placentas from women with SLE and in 1 out of 10 controls.

CONCLUSIONS

In women with SLE, locally produced chemokines in the placenta are increased and may attract and activate neutrophils. This in turn could contribute to placental inflammation and dysfunction and increased risk of placenta-related pregnancy complications.

Anti-IFNαR Mabs for the treatment of systemic lupus erythematosus

INTRODUCTION

The type 1 interferon pathway is known to play a role in the immunopathology of systemic lupus erythematosus (SLE). As a result, biologic agents targeting this pathway have been developed and are currently being investigated in clinical trials.

AREAS COVERED

We review the biologic agents which have been developed to antagonize type I interferons in SLE. We focus on anifrolumab, a type I interferon receptor antagonist, and consider the complexities of defining efficacy in SLE clinical trials.

EXPERT OPINION

Anifrolumab shows promise as an addition to the SLE therapeutic armamentarium. Despite discordant results between its two phase III studies, there is a convincing suggestion of benefit in both trials to encourage the view that this approach might be effective. Data acquired thus far look particularly useful for cutaneous disease. We await data on its effect on renal, pulmonary, cardiac, and central nervous system involvement, on patient reported outcomes, and its safety and efficacy with long-term use.

Effects of Gasdermin D in Modulating Murine Lupus and its Associated Organ Damage

OBJECTIVE

Gasdermin D (GSDMD) is the key executioner of an inflammatory cell death mechanism known as pyroptosis. Recent reports have also implicated GSDMD in other mechanisms of cell death, including apoptosis, necroptosis, and NETosis. Given the role of dysregulated cell death in autoimmune syndromes such as systemic lupus erythematosus (SLE), this study was undertaken in a murine lupus model to investigate whether GSDMD plays a pathogenic role in systemic autoimmunity by promoting inflammatory cell death, leading to increased generation of nuclear autoantigens and autoantibodies.

METHODS

An imiquimod-induced model of SLE was tested in GSDMD^-/- mice (n = 30), with wild-type (WT) mice as controls (n = 34), on a C57BL/6 background. At the time of euthanasia, the mice were examined for serum autoantibodies, immune complex deposition, organ inflammation, immune dysregulation, and type I interferon responses. A model of pristane-induced lung injury in GSDMD^-/- mice (n = 7), with WT mice as controls (n = 10), was used to confirm the pulmonary phenotype. Regulation of various mechanisms of cell death by GSDMD was investigated in the mice.

RESULTS

Unexpectedly, GSDMD^-/- mice developed enhanced mortality, more severe renal and pulmonary inflammation, and exacerbated autoantibody production in response to imiquimod. Pulmonary involvement was also more severe in the absence of GSDMD in mice with pristane-induced lung injury. Compared to WT mice, lack of GSDMD was associated with increased levels of circulating nuclear autoantigens (P < 0.01), anti-double-stranded DNA autoantibodies (P < 0.01), tissue immune complex deposition (P < 0.05), expansion of myeloid cell subsets (P < 0.05), and enhanced B cell activation and plasma cell differentiation (P = 0.001). Moreover, in the absence of GSDMD, enhanced autoantigen generation was associated with increased local induction of cell death in vivo.

CONCLUSION

GSDMD negatively regulates autoantigen generation and immune dysregulation in response to tissue injury and may play previously unappreciated protective roles in systemic autoimmunity.

IFITM proteins inhibit placental syncytiotrophoblast formation and promote fetal demise

Elevated levels of type I interferon (IFN) during pregnancy are associated with intrauterine growth retardation, preterm birth, and fetal demise through mechanisms that are not well understood. A critical step of placental development is the fusion of trophoblast cells into a multinucleated syncytiotrophoblast (ST) layer. Fusion is mediated by syncytins, proteins deriving from ancestral endogenous retroviral envelopes. Using cultures of human trophoblasts or mouse cells, we show that IFN-induced transmembrane proteins (IFITMs), a family of restriction factors blocking the entry step of many viruses, impair ST formation and inhibit syncytin-mediated fusion. Moreover, the IFN inducer polyinosinic:polycytidylic acid promotes fetal resorption and placental abnormalities in wild-type but not in Ifitm-deleted mice. Thus, excessive levels of IFITMs may mediate the pregnancy complications observed during congenital infections and other IFN-induced pathologies.

Immunological adaptations in pregnancy that modulate rheumatoid arthritis disease activity

During pregnancy, the fetus that grows within the maternal uterus is not rejected by the maternal immune system. To enable both tolerance towards the fetus and defence against pathogens, modifications of the maternal immune system occur during gestation. These modifications are able to bring about a natural improvement in disease activity of some autoimmune diseases, such as rheumatoid arthritis (RA). Various mechanisms of the immune system contribute to the phenomenon of pregnancy-related improvement of RA, and the cessation of these immunomodulatory mechanisms after delivery correlates with postpartum disease flare. HLA disparity between mother and fetus, glycosylation of IgG, immunoregulatory pathways, and alterations in innate and adaptive immune cells and their cytokines have important roles in pregnancy and in pregnancy-related amelioration of RA.

Effect of aspirin response signature gene expression on preterm birth and preeclampsia among women with lupus: a pilot study

BACKGROUND

Women with lupus have an increased risk of preeclampsia and preterm birth, and aspirin 81 mg/day is recommended as a preventative measure for preeclampsia. This pilot study quantified the association between a 60-gene aspirin response signature (ARS) gene expression with preterm birth and preeclampsia risk among women with lupus taking aspirin.

METHODS

The analysis included 48 RNA samples from 23 pregnancies in the Duke Autoimmunity Pregnancy Registry. RNA was isolated from peripheral blood, and quantitative polymerase chain reaction was performed for ARS genes. The primary outcome was poor pregnancy outcome (preeclampsia or preterm birth). Gene expression was modeled as a response to presence or absence of a poor pregnancy outcome using linear regression models, stratified by trimester.

RESULTS

Of the 23 pregnancies, nine delivered preterm and four had preeclampsia. Expression of PBX1 and MMD was higher in the second trimester among patients who experienced a poor pregnancy outcome compared to those who did not. However, in a global test of all ARS genes, we identified no association between expression of ARS genes and poor pregnancy outcomes.

CONCLUSION

Our pilot study identified two candidate genes that are reflective of the platelet function response to aspirin. Further work is needed to determine the role of these genes in identifying women with lupus at high risk for preeclampsia and preterm delivery despite aspirin therapy.

Preterm birth phenotypes in women with autoimmune rheumatic diseases: a population-based cohort study

OBJECTIVE

To investigate preterm birth (PTB) phenotypes in women with different autoimmune rheumatic diseases in a large population-based cohort.

DESIGN

Retrospective cohort study.

SETTING

California, USA.

POPULATION

All live singleton births in California between 2007 and 2011 were analysed. Patients with autoimmune disease at delivery were identified by International Classification of Diseases, Ninth Revision , Clinical Modification (ICD-9-CM), codes for systemic lupus erythematosus (SLE), systemic sclerosis (SSc), rheumatoid arthritis (RA), polymyositis/dermatomyositis (DM/PM), and juvenile idiopathic arthritis (JIA).

METHODS

Maternally linked hospital and birth certificate records of 2 481 516 deliveries were assessed (SLE n = 2272, RA n = 1501, SSc n = 88, JIA n = 187, DM/PM n = 38). Multivariable Poisson regression models estimated the risk ratios (RRs) for different PTB phenotypes (relative to term deliveries) for each autoimmune disease compared with the general obstetric population, adjusting for maternal age, race/ethnicity, body mass index, smoking, education, payer, parity, and prenatal care.

MAIN OUTCOME MEASURES

Preterm birth (PTB) was assessed overall (20-36 weeks of gestation) and by subphenotype: preterm prelabour rupture of membranes (PPROM), spontaneous birth, or medically indicated PTB. The risk of PTB overall and for each phenotype was partitioned by gestational age: early (20-31 weeks of gestation) and late (32-36 weeks of gestation).

RESULTS

Risks for PTB were elevated for each autoimmune disease evaluated: SLE (RR 3.27, 95% CI 3.01-3.56), RA (RR 2.04, 95% CI 1.79-2.33), SSc (RR 3.74, 95% CI 2.51-5.58), JIA (RR 2.23, 95% CI 1.54-3.23), and DM/PM (RR 5.26, 95% CI 3.12-8.89). These elevated risks were observed for the majority of PTB phenotypes as well.

CONCLUSIONS

Women with systemic autoimmune diseases appear to have an elevated risk of various PTB phenotypes. Therefore, preconception counselling and close monitoring during pregnancy is crucial.

TWEETABLE ABSTRACT

This study found that women with systemic autoimmune diseases have an elevated risk of preterm birth phenotypes.

Protective and Pathogenic Effects of Interferon Signaling During Pregnancy

Immune regulation at the maternal-fetal interface is complex due to conflicting immunological objectives: protection of the fetus from maternal pathogens and prevention of immune-mediated rejection of the semiallogeneic fetus and placenta. Interferon (IFN) signaling plays an important role in restricting congenital infections as well as in the physiology of healthy pregnancies. In this review, we discuss the antiviral and pathogenic effects of type I IFN (IFN-α, IFN-β), type II IFN (IFN-γ), and type III IFN (IFN-λ) during pregnancy, with an emphasis on mouse and non-human primate models of congenital Zika virus infection. In the context of these animal model systems, we examine the role of IFN signaling during healthy pregnancy. Finally, we review mechanisms by which dysregulated type I IFN responses contribute to poor pregnancy outcomes in humans with autoimmune disease, including interferonopathies and systemic lupus erythematosus.

Shared and Distinct Functions of Type I and Type III Interferons

Type I interferons (IFNs) (IFN-α, IFN-β) and type III IFNs (IFN-λ) share many properties, including induction by viral infection, activation of shared signaling pathways, and transcriptional programs. However, recent discoveries have revealed context-specific functional differences. Here, we provide a comprehensive review of type I and type III IFN activities, highlighting shared and distinct features from molecular mechanisms through physiological responses. Beyond discussing canonical antiviral functions, we consider the adaptive immune priming, anti-tumor, and autoimmune functions of IFNs. We discuss a model wherein type III IFNs serve as a front-line defense that controls infection at epithelial barriers while minimizing damaging inflammatory responses, reserving the more potent type I IFN response for when local responses are insufficient. In this context, we discuss current therapeutic applications targeting these cytokine pathways and highlight gaps in understanding of the biology of type I and type III IFNs in health and disease.

Type I interferon gene expression in antiphospholipid syndrome: Pathogenetic, clinical and therapeutic implications

Type I Interferon gene expression has been shown to play an important role in the pathogenesis of several systemic autoimmune disorders, paving the way for its potential use as a surrogate marker or a therapeutic tool. While the concept of type I interferon signature and its correlation with clinical phenotypes and disease activity, along with anti-interferon targeted therapy have been vastly investigated in patients with systemic lupus erythematosus, there is a paucity of data concerning antiphospholipid syndrome patients. In this review, we summarize the current knowledge on the pathogenetic and clinical implications of type I interferon expression in antiphospholipid syndrome and discuss the therapeutic possibility of targeting molecules along the interferon signaling pathway. A number of recent studies have shown a type I interferon gene expression induction in patients with primary antiphospholipid syndrome via the plasmacytoid dendritic cell pathway, toll like receptors (TLRs) such as TLR7 and TLR9, anti-beta2glycoprotein I antibody-mediated neutrophil activation and neutrophil extracellular traps (NETs) release in a TLR4-dependent fashion, and a subsequent B cell and plasmablast activation. An association between type I interferon expression and several demographic, clinical and laboratory characteristics including age, gender, pregnancy complications such as eclampsia, anti-beta2glycoprotein I antibodies, and a negative correlation with hydroxychloroquine and/or statin use, has been shown. Correlation of high interferon scores to worse outcomes in prospective studies could direct the initiation for a prompt treatment in high-risk populations. Potential therapeutic approaches targeting type I interferon production and signaling pathway components might include anti-interferon or interferon receptor monoclonal antibodies, or an interferon based therapeutic vaccine as was indicated from previous systemic lupus erythematosus studies, TLR inhibitors including hydroxychloroquine and anti-TLR antibodies, plasmacytoid dendritic cell inhibition, adenosine-receptor agonists, and plasmablast targeting treatments. Well-designed studies are needed to further assess the immunomodulatory potential of the above targets for therapeutic intervention in patients with primary antiphospholipid syndrome.

Early Onset Pre-Eclampsia with Nephrotic Range Proteinuria as the Initial Manifestation of Lupus Nephritis: Report of three cases

Early onset pre-eclampsia (pre-eclampsia at less than 34 gestational weeks) is a severe form of preeclampsia; in addition, some women may also develop nephrotic range proteinuria. De novo diagnosis of lupus nephritis (LN) in pregnancy is challenging as it may present with features similar to commonly occurring preeclampsia. We report three cases of early onset pre-eclampsia with nephrotic range proteinuria and subsequent diagnosis of LN at the Women and Children hospital attached to Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India, between 2014 and 2017. These cases highlights the need for further evaluation of the association between nephrotic-range proteinuria and early onset pre-eclampsia. The index of suspicion for underlying LN of these type of cases should be high. Earlier detection of LN will prompt better management that can avert or delay short- and long-term morbidity.

Longitudinal profiling of human blood transcriptome in healthy and lupus pregnancy

Healthy and uncomplicated lupus pregnancies exhibit early and sustained transcriptional modulation of lupus-related pathways. This might contribute to fetal tolerance while predisposing pregnant women to certain infections. Failure to modulate these pathways is associated with lupus pregnancy complications.

Systemic lupus erythematosus carries an increased risk of pregnancy complications, including preeclampsia and fetal adverse outcomes. To identify the underlying molecular mechanisms, we longitudinally profiled the blood transcriptome of 92 lupus patients and 43 healthy women during pregnancy and postpartum and performed multicolor flow cytometry in a subset of them. We also profiled 25 healthy women undergoing assisted reproductive technology to monitor transcriptional changes around embryo implantation. Sustained down-regulation of multiple immune signatures, including interferon and plasma cells, was observed during healthy pregnancy. These changes appeared early after embryo implantation and were mirrored in uncomplicated lupus pregnancies. Patients with preeclampsia displayed early up-regulation of neutrophil signatures that correlated with expansion of immature neutrophils. Lupus pregnancies with fetal complications carried the highest interferon and plasma cell signatures as well as activated CD4⁺ T cell counts. Thus, blood immunomonitoring reveals that both healthy and uncomplicated lupus pregnancies exhibit early and sustained transcriptional modulation of lupus-related signatures, and a lack thereof associates with adverse outcomes.

Type I Interferons in Autoimmune Disease

Type I interferons, which make up the first cytokine family to be described and are the essential mediators of antivirus host defense, have emerged as central elements in the immunopathology of systemic autoimmune diseases, with systemic lupus erythematosus as the prototype. Lessons from investigation of interferon regulation following virus infection can be applied to lupus, with the conclusion that sustained production of type I interferon shifts nearly all components of the immune system toward pathologic functions that result in tissue damage and disease. We review recent data, mainly from studies of patients with systemic lupus erythematosus, that provide new insights into the mechanisms of induction and the immunologic consequences of chronic activation of the type I interferon pathway. Current concepts implicate endogenous nucleic acids, driving both cytosolic sensors and endosomal Toll-like receptors, in interferon pathway activation and suggest targets for development of novel therapeutics that may restore the immune system to health.

Type III Interferons in Antiviral Defenses at Barrier Surfaces

Barrier surfaces such as the epithelium lining the respiratory and gastrointestinal (GI) tracts, the endothelium comprising the blood-brain barrier (BBB), and placental trophoblasts provide key physical and immunological protection against viruses. These barriers utilize nonredundant mechanisms to suppress viral infections including the production of interferons (IFNs), which induce a strong antiviral state following receptor binding. However, whereas type I IFNs control infection systemically, type III IFNs (IFN-λs) control infection locally at barrier surfaces and are often preferentially induced by these cells. In this review we focus on the role of IFN-λ at barrier surfaces, focusing on the respiratory and GI tracts, the BBB, and the placenta, and on how these IFNs act to suppress viral infections.

Interferons and Proinflammatory Cytokines in Pregnancy and Fetal Development

Successful pregnancy requires carefully-coordinated communications between the mother and fetus. Immune cells and cytokine signaling pathways participate as mediators of these communications to promote healthy pregnancy. At the same time, certain infections or inflammatory conditions in pregnant mothers cause severe disease and have detrimental impacts on the developing fetus. In this review, we examine evidence for the role of maternal and fetal immune responses affecting pregnancy and fetal development, both under homeostasis and following infection. We discuss immune responses that are necessary to promote healthy pregnancy and those that lead to congenital disorders and pregnancy complications, with a particular emphasis on the role of interferons and cytokines. Understanding the contributions of the immune system in pregnancy and fetal development provides important insights into the pathogenesis underlying maternal and fetal diseases and sheds insights on possible targets for therapy.

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.

Outcomes of Congenital Zika Disease Depend on Timing of Infection and Maternal-Fetal Interferon Action

Zika virus (ZIKV) infection during pregnancy in humans results in intrauterine growth restriction, spontaneous abortion, and microcephaly. Here, we found that fetus-derived type I interferon (IFN-I) signaling can enhance anti-ZIKV responses and provide clinical benefits to the fetus. Because IFN-λ shares signaling cascades and antiviral functions with IFN-I, we investigated the in vivo effects of IFN-λ in ZIKV-infected pregnant mice. IFN-λ administration during mid-pregnancy reduced ZIKV burden in maternal and fetal organs and alleviated placental injuries and fetal demise. In addition, prophylactic and therapeutic treatment of IFN-λ1 in a human trophoblast line, as well as in primary human amniotic epithelial cells, greatly reduced the ZIKV burden. Our data highlight IFN-λ1 as a potential therapeutic useful for women at risk for congenital Zika disease.

Antiphospholipid Antibodies Inhibit Trophoblast Toll-Like Receptor and Inflammasome Negative Regulators

OBJECTIVE

Women with antiphospholipid antibodies (aPL) are at risk for pregnancy complications associated with poor placentation and placental inflammation. Although these antibodies are heterogeneous, some anti-β₂ -glycoprotein I (anti-β₂ GPI) antibodies can activate Toll-like receptor 4 (TLR-4) and NLRP3 in human first-trimester trophoblasts. The objective of this study was to determine the role of negative regulators of TLR and inflammasome function in aPL-induced trophoblast inflammation.

METHODS

Human trophoblasts were not treated or were treated with anti-β₂ GPI aPL or control IgG in the presence or absence of the common TAM (TYRO3, AXL, and Mer tyrosine kinase [MERTK]) receptor ligand growth arrest-specific protein 6 (GAS6) or the autophagy-inducer rapamycin. The expression and function of the TAM receptor pathway and autophagy were measured by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), Western blotting, and enzyme-linked immunosorbent assay (ELISA). Antiphospholipid antibody-induced trophoblast inflammation was measured by qRT-PCR, activity assays, and ELISA.

RESULTS

Anti-β₂ GPI aPL inhibited trophoblast TAM receptor function by reducing cellular expression of the receptor tyrosine kinases AXL and MERTK and the ligand GAS6. The addition of GAS6 blocked the effects of aPL on the TLR-4-mediated interleukin-8 (IL-8) response. However, the NLRP3 inflammasome-mediated IL-1β response was not affected by GAS6, suggesting that another regulatory pathway was involved. Indeed, anti-β₂ GPI aPL inhibited basal trophoblast autophagy, and reversing this with rapamycin inhibited aPL-induced inflammasome function and IL-1β secretion.

CONCLUSION

Basal TAM receptor function and autophagy may serve to inhibit trophoblast TLR and inflammasome function, respectively. Impairment of TAM receptor signaling and autophagy by anti-β₂ GPI aPL may allow subsequent TLR and inflammasome activity, leading to a robust inflammatory response.

Angiogenic factors in pregnancies of women with antiphospholipid syndrome and systemic lupus erythematosus

OBJECTIVES

An imbalance of angiogenic placental factors such as endoglin, soluble fms-like tyrosine kinase 1(sFlt-1) and placental growth factor (PlGF) has been implicated in the pathophysiology of preeclampsia. This study aimed to evaluate serum levels of sFlt-1, PlGF and endoglin in women with primary and secondary antiphospholipid Syndrome (APS) and systemic lupus erythematosus (SLE) longitudinally through pregnancy.

MATERIAL AND METHODS

Serum levels of sFlt-1, PlGF and endoglin were measured prospectively at 4-week intervals (from gestational weeks 12-36) in 17 women with primary APS (PAPS), 18 women with secondary APS (SAPS), and 23 women with SLE.

RESULTS

6/17 (35%) of women with PAPS, 3/18 (17%) of women with SAPS, and 2/23 (9%) of women with SLE developed early-onset preeclampsia. Women who developed preeclampsia had significantly higher mean sFlt-1 and endoglin levels, higher sFlt-1/PlGF ratios, and lower mean PlGF-levels than women who did not. These changes became statistically significant at 12 weeks for sFlt-1, PlGF and endoglin.

DISCUSSION

Endoglin, sFlt-1 and PlGF are potential early screening parameters for the development of preeclampsia in pregnant women with autoimmune diseases like APS and SLE.

Type I interferons instigate fetal demise after Zika virus infection

Zika virus (ZIKV) infection during pregnancy is associated with adverse fetal outcomes, including microcephaly, growth restriction, and fetal demise. Type I interferons (IFNs) are essential for host resistance against ZIKV, and IFN-α/β receptor (IFNAR)-deficient mice are highly susceptible to ZIKV infection. Severe fetal growth restriction with placental damage and fetal resorption is observed after ZIKV infection of type I IFN receptor knockout (Ifnar1-/-) dams mated with wild-type sires, resulting in fetuses with functional type I IFN signaling. The role of type I IFNs in limiting or mediating ZIKV disease within this congenital infection model remains unknown. In this study, we challenged Ifnar1-/- dams mated with Ifnar1+/- sires with ZIKV. This breeding scheme enabled us to examine pregnant dams that carry a mixture of fetuses that express (Ifnar1+/-) or do not express IFNAR (Ifnar1-/-) within the same uterus. Virus replicated to a higher titer in the placenta of Ifnar1-/- than within the Ifnar1+/- concepti. Yet, rather unexpectedly, we found that only Ifnar1+/- fetuses were resorbed after ZIKV infection during early pregnancy, whereas their Ifnar1-/- littermates continue to develop. Analyses of the fetus and placenta revealed that, after ZIKV infection, IFNAR signaling in the conceptus inhibits development of the placental labyrinth, resulting in abnormal architecture of the maternal-fetal barrier. Exposure of midgestation human chorionic villous explants to type I IFN, but not type III IFNs, altered placental morphology and induced cytoskeletal rearrangements within the villous core. Our results implicate type I IFNs as a possible mediator of pregnancy complications, including spontaneous abortions and growth restriction, in the context of congenital viral infections.

Decidual T Cells Exhibit a Highly Differentiated Phenotype and Demonstrate Potential Fetal Specificity and a Strong Transcriptional Response to IFN

Immune tolerance during human pregnancy is maintained by a range of modifications to the local and systemic maternal immune system. Lymphoid infiltration is seen at the implantation site of the fetal-maternal interface, and decidual NK cells have been demonstrated to facilitate extravillous trophoblast invasion into maternal decidua during the first trimester, optimizing hemochorial placentation. However, although there is considerable T cell infiltration of the maternal decidua, the functional properties of this T cell response remain poorly defined. We investigated the specificity and regulation of CD4⁺ and CD8⁺ T cells obtained from human third trimester decidua and demonstrated that decidual CD4⁺ and CD8⁺ T cells exhibit a highly differentiated effector memory phenotype in comparison with peripheral blood and display increased production of IFN-γ and IL-4. Moreover, decidual T cells proliferated in response to fetal tissue, and depletion of T regulatory cells led to an increase in fetal-specific proliferation. HY-specific T cells were detectable in the decidua of women with male pregnancies and were shown to be highly differentiated. Transcriptional analysis of decidual T cells revealed a unique gene profile characterized by elevated expression of proteins associated with the response to IFN signaling. These data have considerable importance both for the study of healthy placentation and for the investigation of the potential importance of fetal-specific alloreactive immune responses within disorders of pregnancy.

What to Expect When Expecting With Systemic Lupus Erythematosus (SLE): A Population-Based Study of Maternal and Fetal Outcomes in SLE and Pre-SLE

Objective

To assess maternal and fetal outcomes associated with subclinical (pre‐systemic lupus erythematosus [SLE] and SLE presenting up to 5 years postpartum) and prevalent maternal SLE during pregnancy compared with the general population.

Methods

This prospective cohort study used population‐based Swedish registers to identify 13,598 women with first singleton pregnancies registered in the Medical Birth Register (551 prevalent SLE, 65 pre‐SLE within 0–2 years, 133 pre‐SLE within 2–5 years, and 12,847 general population). SLE was defined as ≥2 SLE‐coded discharge diagnoses in the patient register with ≥1 diagnosis from a specialist. Unadjusted risks of adverse pregnancy or birth outcomes were calculated by SLE status, and Cochran‐Armitage tests evaluated trend across exposure groups.

Results

Maternal outcomes such as preeclampsia, hypothyroidism, stroke, and infection were more common among women with SLE. Sixteen percent of prevalent‐SLE pregnancies were diagnosed with preeclampsia compared with 5% of those from the general population. Among the pre‐SLE women, preeclampsia was found in 26% of those with SLE within 2 years postpartum and 13% in those with SLE within 2–5 years postpartum. Similarly, infant outcomes, such as preterm birth, infection, and mortality, were worse among those born to mothers with prevalent SLE and pre‐SLE during pregnancy. The test for trend was significant for most outcomes.

Conclusion

Our data demonstrate that adverse maternal and fetal outcomes are more common in SLE pregnancies. Furthermore, these unfavorable outcomes are observed in pregnancies occurring prior to the diagnosis of SLE. Thus, the underlying immunologic profile of SLE and alterations preceding clinical SLE may contribute to these pregnancy complications.

Early-onset Preeclampsia in Lupus Pregnancy

BACKGROUND

Systemic lupus erythematosus (SLE) is a chronic systemic autoimmune disease that occurs during childbearing years and has been associated with preeclampsia. However, little is known about preeclampsia of early onset, which is associated with severe adverse maternal and perinatal outcomes.

METHODS

Using national population-based Swedish registers we identified women with SLE (≥2 visits with corresponding ICD codes) and a sample without SLE who gave birth to singleton infants 2001-12. Risk ratios (RR) and 95% confidence intervals (CI) for early-onset preeclampsia (defined by ICD codes corresponding to preeclampsia registered at <34 weeks) in SLE women were calculated based on adjusted modified Poisson models for first, subsequent, and all pregnancies.

RESULT

Among 742 births to women with SLE and 10 484 births to non-SLE women, there were 32 (4.3%) and 55 (0.5%) diagnoses of early-onset preeclampsia respectively. SLE was associated with an increased risk of early-onset preeclampsia (RR 7.8, 95% CI 4.8, 12.9, all pregnancies). The association remained similar upon restriction to women without pregestational hypertension. Adjustment for antiphospholipid syndrome (APS)-proxy attenuated the association. RRs for early-onset preeclampsia were smaller for subsequent pregnancies (RR 4.7, 95% CI 2.0, 11.2) compared to first and all (see above).

CONCLUSION

Women with SLE are at increased risk of early-onset preeclampsia and this increased risk may be independent of the traditional risk factors such as pregestational hypertension, APS, BMI, or smoking. Women with SLE during pregnancy should be closely monitored for early-onset preeclampsia and future research needs to identify the non-traditional preeclampsia factors that might cause this serious outcome.