Role of the Macrophage Migration Inhibitory Factor in the Pathophysiology of Pre-Eclampsia

The immune landscape of fetal chorionic villous tissue in term placenta

Introduction

The immune compartment within fetal chorionic villi is comprised of fetal Hofbauer cells (HBC) and invading placenta-associated maternal monocytes and macrophages (PAMM). Recent studies have characterized the transcriptional profile of the first trimester (T1) placenta; however, the phenotypic and functional diversity of chorionic villous immune cells at term (T3) remain poorly understood.

Methods

To address this knowledge gap, immune cells from human chorionic villous tissues obtained from full-term, uncomplicated pregnancies were deeply phenotyped using a combination of flow cytometry, single-cell RNA sequencing (scRNA-seq, CITE-seq) and chromatin accessibility profiling (snATAC-seq).

Results

Our results indicate that, relative to the first trimester, the frequency of fetal macrophages (HBC, proliferating HBC) is significantly reduced, whereas that of infiltrating maternal monocytes/macrophages (PAMM1b, PAMM1a, PAMM2, MAC_1) increased in T3. PAMM1b and HBCs exhibit the most phagocytic capacity at term highlighting their regulatory role in tissue homeostasis in late pregnancy. The transcriptional profiles of resident villous immune subsets exhibit a heightened activation state relative to the relative to T1, likely to support labor and parturition. Additionally, we provide one of the first insights into the chromatin accessibility profile of villous myeloid cells at term. We next stratified our findings by pre-pregnancy BMI since maternal pregravid obesity is associated with several adverse pregnancy outcomes. Pregravid obesity increased inflammatory gene expression, particularly among HBC and PAMM1a subsets, but dampened the expression of antimicrobial genes, supporting a tolerant-like phenotype of chorionic villous myeloid cells. We report a decline in HBC abundance accompanied by an increase in infiltrating maternal macrophages, which aligns with reports of heightened chorionic villous inflammatory pathologies with pregravid obesity. Finally, given the shared fetal yolk-sac origin of HBCs and microglia, we leveraged an in vitro model of umbilical cord blood-derived microglia to investigate the impact of pregravid obesity on fetal neurodevelopment. Our findings reveal increased expression of activation markers albeit dampened phagocytic capacity in microglia with pregravid obesity.

Discussion

Overall, our study highlights immune adaptations in the fetal chorionic villous with gestational age and pregravid obesity, as well as insight towards microglia dysfunction possibly underlying poor neurodevelopmental outcomes in offspring of women with pregravid obesity.

Cordycepin Alleviates Lipopolysaccharides-Induced Preeclampsia-Like Impairments in Rats

INTRODUCTION

Preeclampsia is a serious pregnancy complication that can lead to life-threatening conditions such as seizures, strokes, and even death. A dysregulated inflammatory response in the placenta plays a crucial role in the development of preeclampsia. Cordycepin, known for its anti-inflammatory and antioxidant properties, was the focus of this study, which aimed to investigate its effects on preeclampsia.

METHODS

A preeclampsia-like rat model was established via tail vein injection of lipopolysaccharides (LPS) at a dose of 1 μg/kg in pregnant rats. These rats were then treated with cordycepin at doses of 5, 25, or 50 mg/kg from embryonic day 6 (E6) today 18 (E18). Systolic blood pressures and urinary protein levels were monitored, and pregnancy outcomes, such as fetal body length and weight, were measured. The expression of target genes or proteins was assessed by qPCR, ELISA, and Western blot.

RESULTS

Our findings revealed that cordycepin significantly reduced systolic blood pressure and proteinuria in preeclampsia-like rats. Additionally, cordycepin improved pregnancy outcomes, as shown by increased fetal body length and weight. The treatment also lowered serum sFlt-1 levels, elevated PIGF levels, decreased placental pro-inflammatory cytokine levels (IL-1β, TNF-α, IL-6, MCP-1, and MIP-2), and raised levels of anti-inflammatory cytokine IL-10 level in preeclampsia-like rats. Furthermore, cordycepin helped restore macrophage population imbalances, increasing M1-type macrophage markers (iNOS, TNF-α, and IL-1β) and reducing M2-type macrophage markers (Arg 1, IL-10, and TGF-β).

CONCLUSION

This study suggests that cordycepin alleviates LPS-induced preeclampsia by reducing placental inflammation and correcting the M1/M2 macrophage imbalance, offering potential therapeutic benefits for managing preeclampsia.

Impact of air pollution exposure on cytokines and histone modification profiles at single-cell levels during pregnancy

Fine particulate matter (PM2.5) exposure can induce immune system pathology via epigenetic modification, affecting pregnancy outcomes. Our study investigated the association between PM2.5 exposure and immune response, as well as epigenetic changes using high-dimensional epigenetic landscape profiling using cytometry by time-of-flight (EpiTOF) at the single cell. We found statistically significant associations between PM2.5 exposure and levels of certain cytokines [interleukin-1RA (IL-1RA), IL-8/CXCL8, IL-18, and IL-27)] and histone posttranslational modifications (HPTMs) in immune cells (HPTMs: H3K9ac, H3K23ac, H3K27ac, H2BK120ub, H4K20me1/3, and H3K9me1/2) among pregnant and nonpregnant women. The cord blood of neonates with high maternal PM2.5 exposure showed lower IL-27 than those with low exposure. Furthermore, PM2.5 exposure affects the co-modification profiles of cytokines between pregnant women and their neonates, along with HPTMs in each immune cell type between pregnant and nonpregnant women. These modifications in specific histones and cytokines could indicate the toxicological mechanism of PM2.5 exposure in inflammation, inflammasome pathway, and pregnancy complications.

Maternal hyperthyroidism alters the immunological mediators profile and population of natural killers cells in decidua of rats

Decidual immunological mediators modulate placental formation, decidualization and fetal development. However, the effect of maternal hyperthyroidism on decidual immunology needs further research. The aim of this study was to evaluate the population of uterine natural killer cells (uNKs) and the expression of immunological mediators in the decidua of female rats throughout pregnancy. Wistar rats were used and hyperthyroidism was induced by daily administration of L-thyroxine (T4) throughout pregnancy. The population of uNK cells in decidua was evaluated by immunostaining Lectin DBA, as well as the expression of interferon γ (INFγ), macrophage migration inhibitory factor (MIF), interleukin 15 (IL-15) and inducible nitric oxide synthase (iNOS) at 7, 10, 12, 14 and 19 days of gestation (DG). Maternal hyperthyroidism reduced the DBA+ uNK cell population in the decidua at 7 (P < 0.05) and 10 (P < 0.01) DGs compared to that in the control group, while it increased in the basal decidua (P < 0.05) and metrial gland (P < 0.0001) at the 12th DG. Hyperthyroidism also increased immunostaining of IL-15 (P < 0.0001), INFγ (P < 0.05), and MIF (P < 0.05) in the 7th DG, and increased immunostaining of IL-15 (P < 0.0001) and MIF (P < 0.01) in ^the 10th DG. However, excess thyroxine reduced IL-15 expression in the metrial gland and/or basal decidua in the 12th (P < 0.05), 14th (P < 0.01), and 19th (P < 0.001) DGs, as was also observed for INFγ in the basal decidua (P<0.001) and metrial gland (P < 0.0001) in the 12th DG. Regarding iNOS, an antiinflammatory cytokine, lower expression was observed in the basal decidua of hyperthyroid animals at 7 and 12 DGs (P < 0.05), whereas an increase occurred in the 10th DG (P < 0.05). These data demonstrate that maternal hyperthyroidism in female rats, particularly between 7 and 10 DGs, reduces the population of DBA+ uNKs in the decidua and increases the expression of inflammatory cytokines, suggesting a more proinflammatory environment in early pregnancy caused by this gestational disease.

The Distribution of Foxp3 and CD68 in Preeclamptic and Healthy Placentas: A Histomorphological Evaluation

Preeclampsia is a complication of pregnancy that affects 3-5% of pregnancies and is one of the major causes of maternal/neonatal mortality and morbidities worldwide. We aimed to investigate the distribution of Foxp3+ regulatory T-cells and CD68+ Hofbauer cells in the placenta of preeclamptic and healthy pregnant women with a special focus on correlating these findings with placental histology. Decidua and chorionic villi of the placenta obtained from healthy and preeclamptic pregnancies were evaluated in full-thickness sections. Sections were stained with hematoxylin and eosin and Masson's trichrome and immunostained for Foxp3 and CD68 for histological analyses. The total histomorphological score for placentas was found to be higher in preeclamptic placentas than that in the controls. The CD68 immunoreactivity was higher in the chorionic villi of preeclamptic placentas than that in the controls. The immunoreactivity of Foxp3 was found widely distributed within the decidua in both the groups and did not differ significantly. Interestingly, Foxp3 immunoreactivity in the chorionic villi was found mainly in the villous core and, to a lesser extent, in the syncytiotrophoblasts. We found no significant relation between Foxp3 expressions and morphological changes observed in preeclamptic placentas. Although extensive research is being carried out regarding the pathophysiology of preeclampsia, the findings are still controversial.

SARS-CoV-2 Infection and Candidate Biomarkers

Severe acute respiratory syndrome coronavirus 2 is a virus that can still infect individuals and whose deadly effects continue despite the current vaccines and drugs. Since 2019, many studies on the pathogenesis of the disease have been completed and continue to be done. In addition to the diagnosis and treatment of the disease, many molecules that can be markers of the disease have been investigated. In the early stages of the pandemic, many nonspecific and infection-related laboratory findings and chest computed tomography were used to obtain information about the diagnosis of the disease. The more individual molecules became associated with the disease yet. The purpose of this review is to summarize the impact and role of many molecules associated with coronavirus disease-2019 infection that have been previously used and newly revealed. Numerous studies are summarized in this review. The obtained data show that previously used laboratory findings and new potential biomarkers are not specific to the disease. New potential biomarkers have been associated with the severity of the disease itself, as can be seen with lung imaging and even with routine laboratory findings. One of the important points that are seen frequently in studies is that the effectiveness of these molecules has been shown not only in coronavirus disease-2019 infection but also in many other diseases. This removes the pathogenesis of the disease from being a unique mechanism created by the Severe acute respiratory syndrome coronavirus 2 and provides a general perspective formed by viral or bacterial infections. However, there are still many molecular changes that need to be investigated. Future studies will continue to update themselves with the mutations of the virus.

Downregulation of LINC00221 promotes angiopoiesis in HUVEC and inhibits recruitment of macrophages by augmenting miR-542-3p in trophoblast cells

PURPOSE

To investigate the effects of long intergenic non-protein coding RNA 221 (LINC00221) on preeclampsia (PE) and its mechanism.

METHODS

The expression of LINC00221 was detected in placental tissues from PE patients and normal pregnant women (non-PE). Next, the effects of LINC00221 silencing on trophoblast cells (HTR-8/SVneo and JEG-3) and co-cultured HUVECs or macrophages were evaluated. Afterwards, miR-542-3p was confirmed to bind to LINC00221 directly, and miR-542-3p mimics and inhibitors were transfected into trophoblast cells. Next, a rescue experiment was performed to examine the effect of LINC00221/miR-542-3p axis. Finally, the effect of LINC00221 was also verified in vivo in rat PE models.

RESULTS

The expression of LINC00221 was higher in placental tissues of PE patients than those of non-PE. LINC00221 silencing significantly reduced MCP1 level and increased the VEGF level in trophoblast cells. LINC00221 knockdown in trophoblast cells remarkably enhanced VEGFR expression and the angiopoiesis of HUVECs, and decreased the migration and invasion of macrophages and reduced TNF-α level. Besides, LINC00221 knockdown decreased CHOP, p-IREα, p-PERK, and iNOS expression and increased Trx expression. Notably, LINC00221 negatively regulated miR-542-3p expression. MiR-542-3p overexpression had an effect to that of LINC00221 knockdown, while miR-542-3p inhibition had the opposite effect. Treatment with miR-542-3p inhibitors partially reversed the protective effect of LINC00221 silencing. PE rat model results were consistent with those of in vitro experiments.

CONCLUSIONS

Downregulation of LINC00221 might reduce dysfunction, inflammatory responses, endoplasmic reticulum stress, and oxidative stress, and thereby protect against PE by augmenting miR-542-3p.

Monocytes and macrophages in pregnancy: The good, the bad, and the ugly

A successful human pregnancy requires precisely timed adaptations by the maternal immune system to support fetal growth while simultaneously protecting mother and fetus against microbial challenges. The first trimester of pregnancy is characterized by a robust increase in innate immune activity that promotes successful implantation of the blastocyst and placental development. Moreover, early pregnancy is also a state of increased vulnerability to vertically transmitted pathogens notably, human immunodeficiency virus (HIV), Zika virus (ZIKV), SARS-CoV-2, and Listeria monocytogenes. As gestation progresses, the second trimester is marked by the establishment of an immunosuppressive environment that promotes fetal tolerance and growth while preventing preterm birth, spontaneous abortion, and other gestational complications. Finally, the period leading up to labor and parturition is characterized by the reinstatement of an inflammatory milieu triggering childbirth. These dynamic waves of carefully orchestrated changes have been dubbed the "immune clock of pregnancy." Monocytes in maternal circulation and tissue-resident macrophages at the maternal-fetal interface play a critical role in this delicate balance. This review will summarize the current data describing the longitudinal changes in the phenotype and function of monocyte and macrophage populations in healthy and complicated pregnancies.

Pathogenesis of Pregnancy-Related Complications 1.0 and 2.0

These Special Issue IJMS were dedicated to the major complications responsible for maternal and perinatal morbidity and mortality, such as gestational hypertension (GH), preeclampsia (PE), fetal growth restriction (FGR), gestational diabetes mellitus (GDM), preterm birth, and chronic venous disease [...]

The Complement System, T Cell Response, and Cytokine Shift in Normotensive versus Pre-Eclamptic and Lupus Pregnancy

Successful pregnancy requires an immunological shift with T helper CD4⁺ bias based on disbalance Th1/Th17 versus Th2/T regulatory (Tregs) required to induce tolerance against the semi-allogeneic fetus and placenta and to support fetal growth. Considered a pregnancy-specific hypertensive disorder, pre-eclampsia is characterized by multifaceted organ involvement related to impaired maternal immune tolerance to paternal antigens triggered by hypoxic placental injury as well as excessive local and systemic anti-angiogenic and inflammatory factor synthesis. Both systemic and local Th1/Th2 shift further expands to Th17 cells and their cytokines (IL-17) complemented by suppressive Treg and Th2 cytokines (IL-10, IL-4); alterations in Th17 and Tregs cause hypertension during pregnancy throughout vasoactive factors and endothelial dysfunction, providing an explanatory link between immunological and vascular events in the pathobiology of pre-eclamptic pregnancy. Apart from immunological changes representative of normotensive pregnancy, lupus pregnancy is generally defined by higher serum pro-inflammatory cytokines, lower Th2 polarization, defective and lower number of Tregs, potential blockade of complement inhibitors by anti-phospholipid antibodies, and similar immune alterations to those seen in pre-eclampsia. The current review underpins the immune mechanisms of pre-eclampsia focusing on local (placental) and systemic (maternal) aberrant adaptive and innate immune response versus normotensive pregnancy and pregnancy in systemic autoimmune conditions, particularly lupus.