Exosomal Th1/Th2 cytokines in preeclampsia and HIV-positive preeclamptic women on highly active anti-retroviral therapy

Research progress of exosomes in pathogenesis and treatment of preeclampsia

AIM

Preeclampsia (PE) is a critical and severe disease in obstetrics, which seriously affects maternal and neonatal life safety and long-term prognosis. However, the etiology and pathogenesis of PE are complex, and no unified conclusion has been reached. The types and number of exosomes and their transport substances in PE patients changed. The study of exosomes in PE patients helps clarify the etiology, diagnosis, effective treatment, accurate monitoring, and prognosis.

METHOD

The published articles were reviewed.

RESULTS

Exosomes may affect endothelial and vascular production and function, participate in maternal-fetal immune regulation, and transport substances such as miRNAs, lncRNAs, and proteins involved in the development of PE. Detection of the contents of exosomes can help in the early diagnosis of PE, and can help to improve PE by inhibiting the action of exosomes or preventing their binding to target organs.

CONCLUSION

Exosomes may be involved in the development of PE, and exosomes can be used as markers for predicting the onset of PE and tracking the disease process and determining the prognosis, and exosomes have great potential in the treatment of PE.

Persistent hypertension among postpartum women with comorbid HIV and preeclampsia in Zambia

BACKGROUND

Persistent hypertension is common after preeclampsia and is causally tied to later cardiovascular risks. This study examined whether being HIV-infected and on antiretroviral therapy (ART) is associated with persistent postpartum hypertension among women diagnosed with preeclampsia.

METHODS

We conducted a six-month prospective cohort study at Kanyama and Women and Newborn hospitals from January 01, 2022, to June 30, 2023, among 190 women diagnosed with preeclampsia (59 HIV-positive, 131 HIV-negative). Sociodemographic and clinical characteristics were collected at delivery, six weeks, three months and six months after giving birth. Persistent hypertension was diagnosed if a participant presented with elevated blood pressure ≥140mmHg and/or diastolic blood pressure ≥90mmHg and/or taking medication for hypertension at the study visit. We used a generalized estimating equation to describe the relationship between treated HIV and persistent hypertension six months following delivery.

RESULTS

We retained 136 participants (71.6%) to six months postpartum, at a median age of 30 years. Overall, persistent hypertension at six weeks, three months, and six months postpartum was common (37.4%, 17.1% and 16.9%, respectively). Six-week postpartum prevalence was higher in the HIV group than HIV-negative group (54.6% vs 28.8%, p<0.001), with no measurable difference at three months (24.3% vs 13.2%, p = 0.145) or six months (18.2% vs 16.3%, p = 0.787). Multivariable analysis demonstrates higher odds (adjusted odds ratio [aOR] = 1.68, 95% CI: 1.09-2.60) of persistent hypertension among the HIV+treatment group than HIV-negative counterparts after accounting for age, body mass index and time since delivery.

CONCLUSION

We demonstrate an elevated risk of persistent hypertension among postpartum women with comorbid preeclampsia and treated HIV. Peripartum patients in HIV-endemic settings may benefit from timely detection of hypertension and treatment interventions to improve health outcomes.

Differential proteomics of circulating extracellular vesicles of placental origin isolated from women with early-onset preeclampsia reveal aberrant innate immune and hemostasis processes

PROBLEM

Early-onset preeclampsia (EOPE) is a severe gestational hypertensive disorder with significant feto-maternal morbidity and mortality due to uteroplacental insufficiency. Circulating extracellular vesicles of placental origin (EV-P) are known to be involved in the pathophysiology of EOPE and might serve as an ideal reservoir for its specific biomarkers. Therefore, we aimed to characterize and perform comparative proteomics of circulating EV-P from healthy pregnant and EOPE women before delivery.

METHOD OF STUDY

The EV-P from both groups were isolated using immunoaffinity and were characterized using transmission electron microscopy, dynamic light scattering, nanoparticle tracking analysis, and immunoblotting. Following IgG albumin depletion, the pooled proteins that were isolated from EV-P of both groups were subjected to quantitative TMT proteomics.

RESULTS

Circulating term EV-P isolated from both groups revealed ∼150 nm spherical vesicles containing CD9 and CD63 along with placental PLAP and HLA-G proteins. Additionally, the concentration of EOPE-derived EV-P was significantly increased. A total of 208 proteins were identified, with 26 among them being differentially abundant in EV-P of EOPE women. This study linked the pathophysiology of EOPE to 19 known and seven novel proteins associated with innate immune responses such as complement and TLR signaling along with hemostasis and oxygen homeostasis.

CONCLUSION

The theory suggesting circulating EVs of placental origin could mimic molecular information from the parent organ-"the placenta"-is strengthened by this study. The findings pave the way for possible discovery of novel prognostic and predictive biomarkers as well as provide insight into the mechanisms driving the pathogenesis of EOPE.

Collateral Damage in the Placenta during Viral Infection in Pregnancy: A Possible Mechanism for Vertical Transmission and an Adverse Pregnancy Outcome

In mammals, the placenta is a connection between a mother and a new developing organism. This tissue has a protective function against some microorganisms, transports nutrients, and exchanges gases and excretory substances between the mother and the fetus. Placental tissue is mainly composed of chorionic villi functional units called trophoblasts (cytotrophoblasts, the syncytiotrophoblast, and extravillous trophoblasts). However, some viruses have developed mechanisms that help them invade the placenta, causing various conditions such as necrosis, poor perfusion, and membrane rupture which, in turn, can impact the development of the fetus and put the mother's health at risk. In this study, we collected the most relevant information about viral infection during pregnancy which can affect both the mother and the fetus, leading to an increase in the probability of vertical transmission. Knowing these mechanisms could be relevant for new research in the maternal-fetal context and may provide options for new therapeutic targets and biomarkers in fetal prognosis.

Circulating extracellular vesicles in healthy and pathological pregnancies: A scoping review of methodology, rigour and results

Extracellular vesicles (EVs) play a crucial role in pregnancy, revealed by the presence of placental-derived EVs in maternal blood, their in vitro functionality, and their altered cargo in pregnancy pathologies. These EVs are thought to be involved in the development of pregnancy pathologies, such as pre-eclampsia, pre-term birth, and fetal growth restriction, and have been suggested as a source of biomarkers for gestational diseases. However, to accurately interpret their function and biomarker potential, it is necessary to critically evaluate the EV isolation and characterization methodologies used in pregnant cohorts. In this systematic scoping review, we collated the results from 152 studies that have investigated EVs in the blood of pregnant women, and provide a detailed analysis of the EV isolation and characterization methodologies used. Our findings indicate an overall increase in EV concentrations in pregnant compared to non-pregnant individuals, an increased EV count as gestation progresses, and an increased EV count in some pregnancy pathologies. We highlight the need for improved standardization of methodology, greater focus on gestational changes in EV concentrations, and further investigations into the functionality of EVs. Our review suggests that EVs hold great promise as diagnostic and translational tools for gestational diseases. However, to fully realize their potential, it is crucial to improve the standardization and reliability of EV isolation and characterization methodologies, and to gain a better understanding of their functional roles in pregnancy pathologies.

Preeclampsia-Derived Exosomes Imbalance the Activity of Th17 and Treg in PBMCs from Healthy Pregnant Women

The disturbance of maternofetal immune tolerance is identified as one of the important issues in the pathology of preeclampsia (PE). PE exosomes are believed to possess significant roles in immune abnormalities. In this study, to assess the possible effects of PE exosomes in the pathophysiology of preeclampsia patients, exosomes were isolated from the serum of PE patients and incubated with peripheral blood mononuclear cells (PBMCs) of healthy pregnant women. Also, exosomes from healthy pregnant women were utilized as the control. Th17/Treg ratio in PE and healthy pregnant women and the effects of PE exosomes on expression level of Th17 and Treg transcription factors, as well as their related cytokines in PBMCs of healthy pregnant women, were evaluated. A significant decrease in Treg cell number and increase in Th17 cells and Th17/Treg ratio were observed in PE patients. Following PE-exosome intervention, a significant increase in mRNA expression level of RORγt, IL-17, IL-23, IL-1β, and IL-6, and significant decrease in IL-10 and TGFβ were evident. On the other hand, no significant difference in FoxP3 level was detected. Additionally, increased IL-6, IL-17, IL-23, and IL-1β levels and decreased IL-10 level in the supernatant of cultured PBMCs from healthy pregnant women following PE-exosome intervention were exhibited. However, TGF-β level did not change significantly. Based on our findings, PE exosomes are able to alter the activity of Th17 and Treg cells as well as their related gene expression and cytokine profiles. These findings support the probable role of PE exosomes in PE pathogenesis.

The exosome: a review of current therapeutic roles and capabilities in human reproduction

Exosomes are nano-vesicles (30-150 nm) which may be useful as therapeutic delivery vehicles and as diagnostic biomarkers. Exosomes are produced naturally within the human body and therefore are not prone to immunogenicity effects which would otherwise destroy unelicited foreign bodies. Clinically, they have been regarded as ideal candidates for applications relating to biomarker developments for the early detection of different diseases. Furthermore, exosomes may be of interest as potential drug delivery vehicles, which may improve factors such as bioavailability of loaded molecular cargo, side effect profiles, off-target effects, and pharmacokinetics of drug molecules. In this review, the therapeutic potential of exosomes and their use as clinical biomarkers for early diagnostics will be explored, alongside exosomes as therapeutic delivery vehicles. This review will evaluate techniques for cargo loading, and the capacity of loaded exosomes to improve various reproductive disease states. It becomes important, therefore, to consider factors such as loading efficiency, loading methods, cell viability, exosomal sources, exosome isolation, and the potential therapeutic benefits of exosomes. Issues related to targeted drug delivery will also be discussed. Finally, the variety of therapeutic cargo and the application of appropriate loading methods is explored, in the context of establishing clinical utility. Exosomes have more recently been widely accpeted as potential tools for disease diagnostics and the targeted delivery of certain therapeutic molecules-and in due time exosomes will be utilised more commonly within the clinical setting. Specifically, exosomal biomarkers can be identified and related to various detrimental conditions which occur during pregnancy. Considering, this review will explore the potential future of exosomes as both diagnostic tools and therapeutic delivery vehicles to treat related conditions, including the challenges which exist towards incorporating exosomes within the clinical environment to benefit patients.

Diagnostic biomolecules and combination therapy for pre-eclampsia

Pre-eclampsia (PE), associated with placental malperfusion, is the primary reason for maternal and perinatal mortality and morbidity that can cause vascular endothelial injury and multi-organ injury. Despite considerable research efforts, no pharmaceutical has been shown to stop disease progression. If women precisely diagnosed with PE can achieve treatment at early gestation, the maternal and fetal outcomes can be maximally optimized by expectant management. Current diagnostic approaches applying maternal characteristics or biophysical markers, including blood test, urine analysis and biophysical profile, possess limitations in the precise diagnosis of PE. Biochemical factor research associated with PE development has generated ambitious diagnostic targets based on PE pathogenesis and dissecting molecular phenotypes. This review focuses on current developments in biochemical prediction of PE and the corresponding interventions to ameliorate disease progression, aiming to provide references for clinical diagnoses and treatments.

Immunological Changes in Pregnancy and Prospects of Therapeutic Pla-Xosomes in Adverse Pregnancy Outcomes

Stringent balance of the immune system is a key regulatory factor in defining successful implantation, fetal development, and timely parturition. Interference in these primary regulatory mechanisms, either at adolescence or prenatal state led to adverse pregnancy outcomes. Fertility restoration with the help of injectable gonadotrophins/progesterone, ovulation-inducing drugs, immunomodulatory drugs (corticosteroids), and reproductive surgeries provides inadequate responses, which manifest its own side effects. The development of a potential diagnostic biomarker and an effectual treatment for adverse pregnancy outcomes is a prerequisite to maternal and child health. Parent cell originated bi-layered-intraluminal nano-vesicles (30-150 nm) also known as exosomes are detected in all types of bodily fluids like blood, saliva, breast milk, urine, etc. Exosomes being the most biological residual structures with the least cytotoxicity are loaded with cargo in the form of RNAs (miRNAs), proteins (cytokines), hormones (estrogen, progesterone, etc.), cDNAs, and metabolites making them chief molecules of cell-cell communication. Their keen involvement in the regulation of biological processes has portrayed them as the power shots of cues to understand the disease's pathophysiology and progression. Recent studies have demonstrated the role of immunexosomes (immunomodulating exosomes) in maintaining unwavering immune homeostasis between the mother and developing fetus for a healthy pregnancy. Moreover, the concentration and size of the exosomes are extensively studied in adverse pregnancies like preeclampsia, gestational diabetes mellitus (GDM), and preterm premature rupture of membrane (pPROMs) as an early diagnostic marker, thus giving in-depth information about their pathophysiology. Exosomes have also been engineered physically as well as genetically to enhance their encapsulation efficiency and specificity in therapy for cancer and adverse pregnancies. Successful bench to bedside discoveries and interventions in cancer has motivated developmental biologists to investigate the role of immunexosomes and their active components. Our review summarizes the pre-clinical studies for the use of these power-shots as therapeutic agents. We envisage that these studies will pave the path for the use of immunexosomes in clinical settings for reproductive problems that arise due to immune perturbance in homeostasis either at adolescence or prenatal state.

Quantitative proteomic analysis of serum-purified exosomes identifies putative pre-eclampsia-associated biomarkers

BACKGROUND

The high incidence of pre-eclampsia, which affects 2-7% of all pregnancies, remains a major health concern. Detection of pre-eclampsia before the appearance of clinical symptoms is essential to allow early intervention, and would benefit from identification of plasma/serum biomarkers to help guide diagnosis and treatment. Liquid biopsy has emerged as a promising source of protein biomarkers that circumvents some of the inherent challenges of proteome-wide analysis of plasma/serum. In this respect, purified exosomes have the added benefit of being carriers of intercellular communication both in physiological and pathological conditions.

METHODS

We compared the protein complement of purified exosomes from three different collections of control and pre-eclamptic serum samples, obtained at the end of the second trimester of pregnancy and at delivery. We employed shotgun label-free proteomics to investigate differential protein expression, which was then validated by targeted proteomics.

RESULTS

We developed a purification method that yielded highly enriched exosome preparations. The presence of specific pregnancy protein markers suggested that a significant proportion of purified exosomes derived from tissues related to pregnancy. Quantitative proteomic analyses allowed us to identify 10, 114 and 98 differentially-regulated proteins in the three sample collections, with a high degree of concordance. Functional analysis suggested that these proteins participate in biological processes related to pre-eclampsia, including angiogenesis, inflammation and cell migration. The differential abundance of 66 proteins was validated by targeted proteomics. Finally, we studied the impact of the pre-eclampsia-associated exosomes in the proteome using an in vitro cellular model.

CONCLUSIONS

We have identified and validated differential exosomal proteins in liquid biopsy of pregnant women that open new possibilities for early detection of pre-eclampsia. Additionally, the functional impact of the proteome composition of purified pre-eclamptic exosomes in target cells provides new information to better understand changes in embryo-maternal interactions and, consequently, the pathogenesis of this disease.

Protease inhibitor-based antiretroviral therapy in pregnancy: effects on hormones, placenta, and decidua

The use of antiretroviral therapy (ART) in pregnancy is important for maternal health, and has been successful in reducing vertical transmission rates to almost zero in those taking effective ART regimens with good adherence. However, there are reports of higher rates of low birthweight and preterm births in women with HIV, which can be further exacerbated by ART usage in pregnancy. Protease inhibitors, and ritonavir-boosted lopinavir in particular, might directly contribute to placental and uteroplacental pathology in part by altering plasma concentrations of the essential steroid hormones of pregnancy, progesterone and oestradiol. In this Review, we collate the increasing evidence of dysregulated maternal endocrinology, reproductive physiology, and placental compromise associated with protease inhibitors. Based on findings of placental and decidual effects, we recommend that ritonavir-boosted lopinavir should be avoided in pregnancy, in line with US and European guidelines. Long-term follow-up of children exposed to protease inhibitors in utero is also recommended.

The Potential Role of Serum Exosomes in Preeclampsia

Preeclampsia is a serious pregnancy-specific disease that affects about 5%-8% of pregnant women and is the main reason for the increase in maternal and perinatal mortality. Due to unknown etiology, preeclampsia is still the main cause of increased mortality in maternal and perinatal infants, which is mainly manifested by new hypertension after 20 weeks of pregnancy. As the pathogenesis has not been fully elucidated, early diagnosis and full treatment are lacking. Exosomes secreted from the placenta to the peripheral circulation may be involved in the pathogenesis of preeclampsia and can be detected from the plasma of pregnant women after 6 weeks of pregnancy. Related studies have shown that the levels of exosomes in preeclampsia have changed, and the protein and miRNA expression profiles are also different. Therefore, monitoring changes in plasma exosomes and expression profiles may provide new ideas and new perspectives for the prediction, diagnosis and treatment of preeclampsia.

Maternal HIV infection is associated with distinct systemic cytokine profiles throughout pregnancy in South African women

Maternal HIV infection is associated with adverse pregnancy outcomes, but the mechanisms remain unknown. The course of pregnancy is regulated by immunological processes and HIV infection and antiretroviral therapy (ART) impact key immune mechanisms, which may disrupt the immune programme of pregnancy. We evaluated a broad range of systemic cytokines at each trimester of pregnancy in 56 women living with HIV (WLHIV) and 68 HIV-negative women, who were enrolled in a prospective pregnancy cohort study in Soweto, South Africa. The pro-inflammatory cytokine IP-10 was detected in each trimester in all WLHIV, which was significantly more than in HIV-negative women. The anti-viral cytokine IFNλ1 was detected more frequently in WLHIV, whereas IFNβ and IFNλ2/3 were detected more frequently in HIV-negative women. Th1 cytokines IL-12 and IL-12p70, Th2 cytokine IL-5, and Th17 cytokine IL-17A were detected more frequently in WLHIV throughout pregnancy. Il-6, IL-9, and IL-10 were more commonly detected in WLHIV in the first trimester. Trends of increased detection of Th1 (IL-2, IL-12p70), Th2 (IL-4, Il-5, Il-13) and Th17 (IL-17A, Il-17F, IL-21, IL-22) cytokines were associated with small-for-gestational-age babies. Our findings indicate that maternal HIV/ART is associated with distinct systemic cytokine profiles throughout pregnancy.

Overview of extracellular vesicles in the pathogenesis of preeclampsia†

Preeclampsia (PE) is a leading cause of maternal and fetal-neonatal deaths, and its pathogenesis has been linked to the involvement of extracellular vesicles (EVs). EVs are a heterogeneous group of cell-originated membranous vesicles including exosomes, microvesicles, and apoptotic bodies. EVs transport various bioactive cargos such as lipids, proteins, or nucleic acids, and thus mediate cellular communication and contribute to the proper functioning of cells, organs and processes, including normal pregnancy. Numerous studies have reported that EVs are associated with abnormal levels of soluble fms-like tyrosine kinase-1 (sFlt-1), soluble endoglin (sEng), and placental growth factor (PlGF) in PE. EVs isolated from preeclamptic women have been implicated in trophoblast dysfunction and have been reported to activate endothelium, monocytes, and platelets, and to be involved in defective placentation, imbalanced angiogenesis, and intravascular inflammation. When injected into pregnant rodents, these EVs induced hypertension, proteinuria, and adverse fetal outcomes. Deciphering the contribution of EVs to PE will advance our current understanding of this disorder and may lead to more clinical strategies for the management of PE. Of note, the composition of EV cargos may be characteristic of the status and stages of gestation, providing researchers the possibility of one day using EVs as novel, noninvasive, biomarkers for early screening of PE. Herein, we reviewed the latest research into EVs with emphasis on their role in the pathogenesis of PE and their applications as biomarkers in the early screening of this pregnancy-specific disorder.

Extracellular vesicles in spontaneous preterm birth

Feto-maternal communication helps to maintain pregnancy and contributes to parturition at term and preterm. Endocrine and immune factor are well-reported communication mediators. Recent advances in extracellular vesicle (EV) biology have introduced them as major communication channels between the mother and fetus. EVs are round structures with a lipid bilayer membrane. EVs are generally categorized based on their size and mode of biogenesis. The most commonly reported EVs are exosomes with a size range of 30-160 nm that are formed inside the intraluminal vesicles of multivesicular body. Microvesicles (MVs) are larger than > 200 nm and formed by outward budding of plasma membrane. Vesicles are released from all cells and carry various factors that reflect the physiologic state of cell at the time of their release. Analysis of vesicle provides a snapshot of origin cell. Recent studies in perinatal medicine have shown that exosomes are key communicators between feto-maternal units, and they can cross placenta. Fetal-derived exosomes released under term labor-associated conditions can cause parturition-associated changes in maternal uterine tissues. Exosomes carrying inflammatory cargo can cause preterm birth in animal models suggesting their functional role in parturition. A few reports have profiled differences between exosome cargos from term and preterm pregnancies and indicated their biomarker potential to predict high-risk pregnancy status. There are hardly any reports on MVs and their functional roles in reproduction. Herein, we review of EVs and MVs, their characteristics, function, and usefulness predicting adverse pregnancy complications such as preterm birth.

Placental Microbial Colonization and Its Association With Pre-eclampsia

The existence and role of the microbiome in regulating physiological and pathophysiological conditions including metabolism, energy homeostasis, immune tolerance, behavior, obesity, diabetes, and cardiovascular-related diseases is of immense interest. It is now clear that the human placenta is not sterile, but rather colonized with microbes. The placental and vaginal microbiomes are distinct however, the placental microbiome is comparable with the oral microbiome, with a limited variation when compared with the gut microbiome. Pre-eclampsia (PE), a pregnancy-specific hypertensive disorder, remains the leading cause of maternal-fetal morbidity and mortality. This is largely due to the lack of a clear etiology of PE and consequently, diagnostic strategies, and treatment are sub-optimal. The present review focuses on the current understanding of the placental microbiome and its implication in the etiology of PE. It provides a perspective on the alteration of placental microbiome as a possible therapeutic approach in the prevention and management of PE.

From animal models to patients: the role of placental microRNAs, miR-210, miR-126, and miR-148a/152 in preeclampsia

Placental microRNAs (miRNAs) regulate the placental transcriptome and play a pathological role in preeclampsia (PE), a hypertensive disorder of pregnancy. Three PE rodent model studies explored the role of placental miRNAs, miR-210, miR-126, and miR-148/152 respectively, by examining expression of the miRNAs, their inducers, and potential gene targets. This review evaluates the role of miR-210, miR-126, and miR-148/152 in PE by comparing findings from the three rodent model studies with in vitro studies, other animal models, and preeclamptic patients to provide comprehensive insight into genetic components and pathological processes in the placenta contributing to PE. The majority of studies demonstrate miR-210 is upregulated in PE in part driven by HIF-1α and NF-κBp50, stimulated by hypoxia and/or immune-mediated processes. Elevated miR-210 may contribute to PE via inhibiting anti-inflammatory Th2-cytokines. Studies report an up- and downregulation of miR-126, arguably reflecting differences in expression between cell types and its multifunctional capacity. MiR-126 may play a pro-angiogenic role by mediating the PI3K-Akt pathway. Most studies report miR-148/152 family members are upregulated in PE. Evidence suggests they may inhibit DNA methylation of genes involved in metabolic and inflammatory pathways. Given the genetic heterogeneity of PE, it is unlikely that a single placental miRNA is a suitable therapeutic target for all patients. Investigating miRNAs in PE subtypes in patients and animal models may represent a more appropriate approach going forward. Developing methods for targeting placental miRNAs and specific placental cell types remains crucial for research seeking to target placental miRNAs as a novel treatment for PE.