Manipulating CD4+ T Cell Pathways to Prevent Preeclampsia

Preeclampsia (PreE) is a placental disorder characterized by hypertension (HTN), proteinuria, and oxidative stress. Individuals with PreE and their children are at an increased risk of serious short- and long-term complications, such as cardiovascular disease, end-organ failure, HTN, neurodevelopmental disorders, and more. Currently, delivery is the only cure for PreE, which remains a leading cause of morbidity and mortality among pregnant individuals and neonates. There is evidence that an imbalance favoring a pro-inflammatory CD4+ T cell milieu is associated with the inadequate spiral artery remodeling and subsequent oxidative stress that prime PreE’s clinical symptoms. Immunomodulatory therapies targeting CD4+ T cell mechanisms have been investigated for other immune-mediated inflammatory diseases, and the application of these prevention tactics to PreE is promising, as we review here. These immunomodulatory therapies may, among other things, decrease tumor necrosis factor alpha (TNF-α), cytolytic natural killer cells, reduce pro-inflammatory cytokine production [e.g. interleukin (IL)-17 and IL-6], stimulate regulatory T cells (Tregs), inhibit type 1 and 17 T helper cells, prevent inappropriate dendritic cell maturation, and induce anti-inflammatory cytokine action [e.g. IL-10, Interferon gamma (IFN-γ)]. We review therapies including neutralizing monoclonal antibodies against TNF-α, IL-17, IL-6, and CD28; statins; 17-hydroxyprogesterone caproate, a synthetic hormone; adoptive exogenous Treg therapy; and endothelin-1 pathway inhibitors. Rebalancing the maternal inflammatory milieu may allow for proper spiral artery invasion, placentation, and maternal tolerance of foreign fetal/paternal antigens, thereby combatting early PreE pathogenesis.

Acute Atherosis Lesions at the Fetal-Maternal Border: Current Knowledge and Implications for Maternal Cardiovascular Health

Decidua basalis, the endometrium of pregnancy, is an important interface between maternal and fetal tissues, made up of both maternal and fetal cells. Acute atherosis is a uteroplacental spiral artery lesion. These patchy arterial wall lesions containing foam cells are predominantly found in the decidua basalis, at the tips of the maternal arteries, where they feed into the placental intervillous space. Acute atherosis is prevalent in preeclampsia and other obstetric syndromes such as fetal growth restriction. Causal factors and effects of acute atherosis remain uncertain. This is in part because decidua basalis is challenging to sample systematically and in large amounts following delivery. We summarize our decidua basalis vacuum suction method, which facilitates tissue-based studies of acute atherosis. We also describe our evidence-based research definition of acute atherosis. Here, we comprehensively review the existing literature on acute atherosis, its underlying mechanisms and possible short- and long-term effects. We propose that multiple pathways leading to decidual vascular inflammation may promote acute atherosis formation, with or without poor spiral artery remodeling and/or preeclampsia. These include maternal alloreactivity, ischemia-reperfusion injury, preexisting systemic inflammation, and microbial infection. The concept of acute atherosis as an inflammatory lesion is not novel. The lesions themselves have an inflammatory phenotype and resemble other arterial lesions of more extensively studied etiology. We discuss findings of concurrently dysregulated proteins involved in immune regulation and cardiovascular function in women with acute atherosis. We also propose a novel hypothesis linking cellular fetal microchimerism, which is prevalent in women with preeclampsia, with acute atherosis in pregnancy and future cardiovascular and neurovascular disease. Finally, women with a history of preeclampsia have an increased risk of premature cardiovascular disease. We review whether presence of acute atherosis may identify women at especially high risk for premature cardiovascular disease.

Antenatal Mesenchymal Stromal Cell Extracellular Vesicle Treatment Preserves Lung Development in a Model of Bronchopulmonary Dysplasia Due to Chorioamnionitis

Background: Antenatal stressors such as chorioamnionitis (CA) increase the risk for bronchopulmonary dysplasia (BPD). Studies have shown that experimental BPD can be ameliorated by postnatal treatment with mesenchymal stromal cell-derived extracellular vesicles (MEx). However, the antenatal efficacy of MEx to prevent BPD is unknown. Objective: To determine whether antenatal MEx therapy attenuates intrauterine inflammation and preserves lung growth in a rat model of CA-induced BPD. Methods: At embryonic day (E)20, rat litters were treated with intra-amniotic injections of saline, endotoxin (ETX) to model chorioamnionitis, MEx, or ETX plus MEx followed by cesarean section delivery with placental harvest at E22. Placental and lung evaluations were conducted at day 0 and day 14, respectively. To assess the effects of ETX and MEx on lung growth in vitro, E15 lung explants were imaged for distal branching. Results: Placental tissues from ETX-exposed pregnancies showed increased expression of inflammatory markers NLRP-3 and IL-1ß and altered spiral artery morphology. Additionally, infant rats exposed to intrauterine ETX had reduced alveolarization and pulmonary vessel density (PVD), increased right ventricular hypertrophy (RVH), and decreased lung mechanics. Intrauterine MEx therapy of ETX-exposed pups reduced inflammatory cytokines, normalized spiral artery architecture, and preserved distal lung growth and mechanics. In vitro studies showed that MEx treatment enhanced distal lung branching and increased VEGF and SPC gene expression. Conclusions: Antenatal MEx treatment preserved distal lung growth and reduced intrauterine inflammation in a model of CA-induced BPD. We speculate that MEx may provide a novel therapeutic strategy to prevent BPD due to antenatal inflammation.

Role of GRK2 in Trophoblast Necroptosis and Spiral Artery Remodeling: Implications for Preeclampsia Pathogenesis

Graphical AbstractLv et al. show that trophoblastic GRK2 deficiency could promote placenta dysfunction and PE-like phenotype by activating necroptosis in trophoblasts, then inducing cytokine disturbance in circulation.

Vascular Dysfunction in Preeclampsia

Preeclampsia is a life-threatening pregnancy-associated cardiovascular disorder characterized by hypertension and proteinuria at 20 weeks of gestation. Though its exact underlying cause is not precisely defined and likely heterogenous, a plethora of research indicates that in some women with preeclampsia, both maternal and placental vascular dysfunction plays a role in the pathogenesis and can persist into the postpartum period. Potential abnormalities include impaired placentation, incomplete spiral artery remodeling, and endothelial damage, which are further propagated by immune factors, mitochondrial stress, and an imbalance of pro- and antiangiogenic substances. While the field has progressed, current gaps in knowledge include detailed initial molecular mechanisms and effective treatment options. Newfound evidence indicates that vasopressin is an early mediator and biomarker of the disorder, and promising future therapeutic avenues include mitigating mitochondrial dysfunction, excess oxidative stress, and the resulting inflammatory state. In this review, we provide a detailed overview of vascular defects present during preeclampsia and connect well-established notions to newer discoveries at the molecular, cellular, and whole-organism levels.

Human placental bed transcriptomic profiling reveals inflammatory activation of endothelial cells in preeclampsia

Rationale: Functional characteristics of endothelial cells (ECs) within the human placental bed are unknown and may provide insight into the adaptive biology of ECs in disorders of vascular remodelling like preeclampsia. Objective: To determine transcriptional profiles of human placental bed ECs and systemic biomarker profiles in women with normal pregnancy, and women with preeclampsia, a condition characterized by extensive EC dysfunction, poor development of spiral arteries underlying the placenta and long-term susceptibility to atherosclerosis and hypertension. Methods & results: We obtained biopsy samples from the uterine placental bed, of five women with preeclampsia with fetal growth restriction (FGR) due to impaired spiral artery development and four controls undergoing Caesarean section. CD31+CD146+ ECs were isolated and sorted by flow cytometry for RNA-sequencing using CEL-Seq2 protocol. Data were analyzed by unsupervised clustering, gene set enrichment (GSEA) and pathway analysis. 67 circulating biomarkers of EC function and inflammation were measured in 20 women with preeclampsia with FGR and 20 controls by multiplex immunoassay. Transcriptional profiling showed various differentially expressed genes (FDR<0.05) in placental bed ECs of preeclampsia patients, with enhanced activity of pathways associated with vasoconstriction, platelet activation and innate immunity. GSEA was suggestive of a VEGF- and PlGF deprived state of preeclampsia-derived ECs. Moreover, the transcriptomic profile was similar to that of human umbilical vein endothelial cells (HUVECs) treated with plasma from preeclampsia patients, pointing towards a central role for circulating factors in EC dysfunction. Unsupervised clustering of subjects by EC-related circulating factors identified distinct profiles for healthy pregnancy and preeclampsia, in particular for those women with low platelets and elevated liver enzymes, which was predominantly driven by sFLT-1, endoglin, PlGF, leptin, SAA-1 and sICAM-1. Conclusions: We revealed inflammatory activation of EC and a key role for systemic factors in EC dysfunction in women with preeclampsia associated with impaired spiral artery development.

Cross Sectional Study of Zinc, Copper and Magnesium Levels in Preeclampsia and Normal Pregnancy

Preeclampsia is a pregnancy related high blood pressure disorder. It involves defective trophoblast invasion and decreased spiral artery remodelling. Alterations in micronutrients have been identified as one of the risk factor of preeclampsia. In this study we have estimated the levels of zinc, copper, iron and magnesium in preeclampsia and normal pregnant women. Our study revealed a significant decrease of zinc, copper and magnesium levels and significant increase of iron levels in preeclampsia compared to normal pregnant women. Thus assessment of micronutrients in pregnancy helps in decreasing the incidence of preeclampsia. Keywords: Preeclampsia, Zinc, Copper, Iron, Magnesium.