Expression of ADAMTS13 in Normal and Abnormal Placentae and Its Potential Role in Angiogenesis and Placenta Development

Increased Complement Activation and Decreased ADAMTS13 Activity Are Associated with Genetic Susceptibility in Patients with Preeclampsia/HELLP Syndrome Compared to Healthy Pregnancies: An Observational Case-Controlled Study

Preeclampsia is a progressive multi-systemic disorder characterized by proteinuria, critical organ damage, and new-onset hypertension. It can be further complicated by HELLP syndrome (hemolysis, elevated liver enzymes, low platelets), resulting in critical liver or renal damage, disseminated coagulation, and grand mal seizures. This study aimed to examine the involvement of ADAMTS13, von Willebrand, and the complement system in the pathogenesis of preeclampsia/HELLP syndrome. We studied 30 Caucasian preeclamptic pregnant women and a control group of 15 healthy pregnancies. Genetic sequencing of ADAMTS13 and complement regulatory genes (MiniSeq System, Illumina) was performed. The modified Ham test was used to check for complement activation, ADAMTS13 activity, von Willebrand antigen (vWFAg) levels, and soluble C5b-9 levels were measured. Patients with preeclampsia had a decreased ADAMTS13 activity and increased C5b-9 levels. The vWFAg was significantly correlated with ADAMTS13 activity (r = 0.497, p = 0.003). Risk-factor variants were found in the genes of ADAMTS13, C3, thrombomodulin, CFB, CFH, MBL2, and, finally, MASP2. A portion of pregnant women with preeclampsia showed a decline in ADAMTS13 activity, correlated with vWFAg levels. These patients also exhibited an elevated complement activation and high-risk genetic variants in regulatory genes. Further research is needed to determine if these factors can serve as reliable biomarkers.

Alterations in the von Willebrand factor/ADAMTS-13 axis in preeclampsia

BACKGROUND

Preeclampsia is a gestational hypertensive disorder characterized by maternal endothelial activation and increased ratio of soluble fms-like tyrosine kinase-1 (sFlt-1) inhibitor to placental growth factor (PlGF). The von Willebrand factor (VWF)/ADAMTS-13 axis is of interest because of the underlying endothelial activation and clinical overlap with pregnancy-associated thrombotic thrombocytopenic purpura.

OBJECTIVES

To assess VWF, ADAMTS-13, and VWF/ADAMTS-13 ratio in preeclampsia and look for associations with sFlt-1/PlGF ratio and clinical features.

METHODS

Thirty-four preeclampsia cases and 48 normal pregnancies were assessed in a case-control study. Twelve normal pregnancies in women with a history of preeclampsia formed an additional comparator group. VWF antigen (VWF:Ag) and VWF activity (VWF:Ac [VWF:glycoprotein IbM]) were measured via automated immunoturbidimetric assay, ADAMTS-13 activity was measured via fluorescence resonance energy transfer-VWF73 assay, and sFlt-1 and PlGF were measured via enzyme-linked immunosorbent assay.

RESULTS

VWF:Ag was higher in preeclampsia than in normal pregnancy (median, 3.07 vs 1.87 IU/mL; P < .0001). ADAMTS-13 activity was slightly lower (median, 89.6 vs 94.4 IU/dL; P = .02), with no severe deficiencies. Significant elevations in VWF:Ac were not observed in preeclampsia, resulting in reduced VWF:Ac/VWF:Ag ratios (median, 0.77 vs 0.97; P < .0001). VWF:Ag/ADAMTS-13 ratios were significantly higher in preeclampsia (median, 3.42 vs 2.06; P < .0001), with an adjusted odds ratio of 19.2 for a ratio of >2.7 (>75th centile of normal pregnancy). Those with a history of preeclampsia had similar ratios to normal pregnant controls. VWF:Ag/ADAMTS-13 and sFlt-1/PlGF were not correlated. However, percentage reduction in platelets correlated positively with VWF:Ac (P = .01), VWF:Ac/VWF:Ag ratio (P = .004), and sFlt-1/PlGF ratio (P = .01).

CONCLUSION

The VWF/ADAMTS-13 axis is significantly altered in preeclampsia. Further investigation of potential clinical utility is warranted.

ADAMTS13 regulates angiogenic markers via Ephrin/Eph signaling in human mesenchymal stem cells under serum-deprivation stress

Mesenchymal stem cells (MSCs) are known to facilitate angiogenesis and promote neo-vascularization via secretion of trophic factors. Here, we explored the molecular mechanism adopted by ADAMTS13 in modulating the expression of some key angiogenic markers in human umbilical cord-derived MSCs under serum-deprivation stress. Wharton's jelly MSCs (WJ-MSCs) were isolated from the perivascular region of human umbilical cords by explant culture. ADAMTS13 was upregulated at both mRNA and protein levels in WJ-MSCs under serum-deprivation stress. Correspondingly, some key angiogenic markers were also seen to be upregulated. By screening signaling pathways, p38 and JNK pathways were identified as negative and positive regulators for expression of ADAMTS13, and the angiogenic markers, respectively. Our results also indicated the Notch pathway and p53 as other probable partners modulating the expression of ADAMTS13 and the angiogenic markers. Knockdown of ADAMTS13 using siRNA led to reversal in the expression of these angiogenic markers. Further, ADAMTS13 was shown to act via the EphrinB2/EphB4 axis followed by ERK signaling to control expression of the angiogenic markers. Interestingly, stronger expression levels were noted for ADAMTS13, VEGF and PDGF under a more stringent nutrient stress condition. Thus, we highlight a novel role of ADAMTS13 in WJ-MSCs under nutrient stress condition.

Synthesis and characterization of a silk fibroin/placenta matrix hydrogel for breast reconstruction

Reconstructive surgery is a complex and demanding interdisciplinary field. One of the major challenges is the production of sizeable, implantable, inexpensive bioprostheses such as breast implants. In this study, porous hybrid hydrogels were fabricated by a combinatorial method using decellularized human placenta (dHplacenta) and silk fibroin. Histology was used to confirm the acellularity of the dHplacenta. The physio-chemical properties of the hydrogels were evaluated using SEM, FTIR, and rheological assays. The synthesized hydrogels exhibited a uniform 3-D microstructure with an interconnected porous network, and the hybrid hydrogels with a 30/70 ratio had improved mechanical properties compared to the other hydrogels. Hybrid hydrogels were also cultured with adipose-derived mesenchymal stem cells (ADSCs). Liposuction was used to obtain adipose tissue from patients, which was then characterized using flow cytometry and karyotyping. The results showed that CD34 and CD31 were downregulated, whereas CD105 and CD90 were upregulated in ADSCs, indicating a phenotype resembling to that of mesenchymal stem cells from the human bone marrow. Moreover, after re-cellularized hydrogel, the live/dead assay and SEM analysis confirmed that most viability and cellular expansion on the hydrogels contained higher ratios of dHplacenta (30/70) than the other two groups. All these findings recapitulated that the 30/70 dHplacenta/silk fibroin hydrogel can perform as an excellent substrate for breast tissue engineering applications.

ADAMTS13 inhibits H2O2-induced human venous endothelial cell injury to attenuate deep-vein thrombosis by blocking the p38/ERK signaling pathway

Deep vein thrombosis (DVT) is a common complication in hematologic malignancies and immunologic disorders. Endothelial cell injury and dysfunction comprise the critical contributor for the development of DVT. A disintegrin and metalloproteinase with thrombospondin motifs 13 (ADAMTS13), a plasma metalloprotease that cleaves von Willebrand factor, acts as a critical regulator in normal hemostasis. This study was aimed to explore the role of ADAMTS13 in endothelial cell injury during DVT and the possible mechanism. First, human umbilical vein endothelial cells (HUVECs) were exposed to hydrogen peroxide (H2O2). Then, the mRNA and protein expressions of ADAMTS13 were evaluated with the reverse transcription-quantitative polymerase chain reaction and western blot. After treatment with recombinant ADAMTS13 (rADAMTS13; rA13), the viability and apoptosis of H2O2-induced HUVECs were assessed by cell counting kit-8 assay and terminal-deoxynucleoitidyl transferase-mediated nick end labeling staining. In addition, the levels of prostaglandin F1-alpha, endothelin-1, and reactive oxygen species were detected using the enzyme-linked immunosorbent assay and dichloro-dihydro-fluorescein diacetate assay. The expressions of proteins related to p38/extracellular signal-regulated kinase (ERK) signaling pathway were estimated with the western blot. Then, p79350 (p38 agonist) was used to pretreat cells to analyze the regulatory effects of rA13 on p38/ERK signaling in H2O2-induced HUVEC injury. The results revealed that ADAMTS13 expression was significantly downregulated in H2O2-induced HUVECs. The reduced viability and increased apoptosis of HUVECs induced by H2O2 were revived by ADAMTS13. ADAMTS13 also suppressed the oxidative stress in HUVECs after H2O2 treatment. Besides, ADAMTS13 was found to block p38/ERK signaling pathway, and p79350 reversed the impacts of ADAMTS13 on the damage of HUVECs induced by H2O2. To sum up, ADAMTS13 could alleviate H2O2-induced HUVEC injury through the inhibition of p38/ERK signaling pathway.

The effects of coagulation factors on the risk of endometriosis: a Mendelian randomization study

BACKGROUND

Endometriosis is recognized as a complex gynecological disorder that can cause severe pain and infertility, affecting 6-10% of all reproductive-aged women. Endometriosis is a condition in which endometrial tissue, which normally lines the inside of the uterus, deposits in other tissues. The etiology and pathogenesis of endometriosis remain ambiguous. Despite debates, it is generally agreed that endometriosis is a chronic inflammatory disease, and patients with endometriosis appear to be in a hypercoagulable state. The coagulation system plays important roles in hemostasis and inflammatory responses. Therefore, the purpose of this study is to use publicly available GWAS summary statistics to examine the causal relationship between coagulation factors and the risk of endometriosis.

METHODS

To investigate the causal relationship between coagulation factors and the risk of endometriosis, a two-sample Mendelian randomization (MR) analytic framework was used. A series of quality control procedures were followed in order to select eligible instrumental variables that were strongly associated with the exposures (vWF, ADAMTS13, aPTT, FVIII, FXI, FVII, FX, ETP, PAI-1, protein C, and plasmin). Two independent cohorts of European ancestry with endometriosis GWAS summary statistics were used: UK Biobank (4354 cases and 217,500 controls) and FinnGen (8288 cases and 68,969 controls). We conducted MR analyses separately in the UK Biobank and FinnGen, followed by a meta-analysis. The Cochran's Q test, MR-Egger intercept test, and leave-one-out sensitivity analyses were used to assess the heterogeneities, horizontal pleiotropy, and stabilities of SNPs in endometriosis.

RESULTS

Our two-sample MR analysis of 11 coagulation factors in the UK Biobank suggested a reliable causal effect of genetically predicted plasma ADAMTS13 level on decreased endometriosis risk. A negative causal effect of ADAMTS13 and a positive causal effect of vWF on endometriosis were observed in the FinnGen. In the meta-analysis, the causal associations remained significant with a strong effect size. The MR analyses also identified potential causal effects of ADAMTS13 and vWF on different sub-phenotypes of endometrioses.

CONCLUSIONS

Our MR analysis based on GWAS data from large-scale population studies demonstrated the causal associations between ADAMTS13/vWF and the risk of endometriosis. These findings suggest that these coagulation factors are involved in the development of endometriosis and may represent potential therapeutic targets for the management of this complex disease.

The impact of maternal ABO blood type on obstetric and perinatal outcomes after frozen embryo transfer

RESEARCH QUESTION

Does the maternal ABO blood type affect obstetric and perinatal outcomes following frozen embryo transfer (FET)?

DESIGN

A retrospective study was performed at a university-affiliated fertility centre, involving women with singleton and twin deliveries conceived by FET. Subjects were divided into four groups based on ABO blood type. The primary end-points were obstetric and perinatal outcomes.

RESULTS

A total of 20,981 women were involved, with 15,830 having singletons and 5151 delivering twins. In singleton pregnancies, women with blood group B had a slight but significantly increased risk of gestational diabetes mellitus compared to women with blood group O (adjusted odds ratio [aOR] 1.16; 95% confidence interval [CI] 1.01-1.34). Furthermore, singletons born to women with the B antigen (blood type B or AB) were more likely to be large for gestational age (LGA) and with macrosomia. In twin pregnancies, blood type AB was related to a decreased risk of hypertensive diseases of pregnancy (aOR 0.58; 95% CI 0.37-0.92), while blood type A was associated with a higher risk of placenta praevia (aOR 2.04; 95% CI 1.15-3.60). When compared with the O blood group, twins from the AB blood group had a lower risk of low birthweight (aOR 0.83; 95% CI 0.71-0.98) but a higher risk of LGA (aOR 1.26; 95% CI 1.05-1.52).

CONCLUSIONS

This study demonstrates that the ABO blood group may influence the obstetric and perinatal outcomes for both singletons and twins. These findings emphasize that patient characteristics could be, at least partly, responsible for adverse maternal and birth outcomes following IVF.

Hypercoagulability and Inflammatory Markers in a Case of Congenital Thrombotic Thrombocytopenic Purpura Complicated by Fetal Demise

BACKGROUND

Congenital thrombotic thrombocytopenic purpura (cTTP) is a rare disorder caused by an inherited genetic deficiency of ADAMTS13 and affects less than one per million individuals. Patients who are diagnosed with TTP during pregnancy are at increased risk of maternal and fetal complications including fetal demise. We present a case of a 32-year-old G3P0 (gravida 3, para 0) who presented at 20 weeks gestation with a new diagnosis of congenital TTP (cTTP) and fetal demise.

METHODS

We describe the pathophysiology of pregnancy complications in a patient with cTTP using platelet procoagulant membrane dynamics analysis and quantitative proteomic studies, compared to four pregnant patients with gestational hypertension, four pregnant patients with preeclampsia, and four healthy pregnant controls.

RESULTS

The cTTP patient had increased P-selectin, tissue factor expression, annexin-V binding on platelets and neutrophils, and localized thrombin generation, suggestive of hypercoagulability. Among 15 proteins that were upregulated, S100A8 and S100A9 were distinctly overexpressed.

CONCLUSIONS

There is platelet-neutrophil activation and interaction, platelet hypercoagulability, and proinflammation in our case of cTTP with fetal demise.

Maternal and fetal outcomes of pregnancy occurring after a diagnosis of immune-mediated thrombotic thrombocytopenic purpura

Pregnancy is a well-established trigger for a first episode or relapse of immune thrombotic thrombocytopenic purpura (iTTP). Other outcomes of subsequent pregnancy after a diagnosis of iTTP are less well described. We conducted this retrospective cohort study to evaluate maternal and fetal outcomes of pregnancy in women with prior iTTP from the Johns Hopkins Thrombotic Microangiopathy Cohort. Of 168 women in the cohort, 102 were of reproductive age at diagnosis. Fourteen pregnancies (in 9 women) that occurred after the initial iTTP episode were included in the analysis. iTTP relapse occurred in 9 (64%) pregnancies. Out of the 9 instances of relapse, 5 relapses occurred in 2 women. Seven pregnancies (50%) ended in fetal death or miscarriage in the setting of iTTP relapse and three were electively terminated due to fear of relapse. Four pregnancies (50% of the 8 that progressed beyond 20 weeks) were complicated by preeclampsia or HELLP syndrome, which is over ten-fold higher than that of the general population. No maternal deaths occurred. Only 4 pregnancies resulted in live births, of which, 2 were pre-term. Pregnancy in women with prior iTTP is associated with a substantial risk of iTTP relapse and fetal loss. Preeclampsia and HELLP syndrome is also more common than that in the general population. ADAMTS13 monitoring and preemptive therapy may improve pregnancy outcomes, which needs to be evaluated prospectively.

Role of ADAM and ADAMTS Disintegrin and Metalloproteinases in Normal Pregnancy and Preeclampsia

Normal pregnancy (NP) involves intricate processes starting with egg fertilization, proceeding to embryo implantation, placentation and gestation, and culminating in parturition. These pregnancy-related processes require marked uteroplacental and vascular remodeling by proteolytic enzymes and metalloproteinases. A disintegrin and metalloproteinase (ADAM) and ADAM with thrombospondin motifs (ADAMTS) are members of the zinc-dependent family of proteinases with highly conserved protein structure and sequence homology, which include a pro-domain, and a metalloproteinase, disintegrin and cysteine-rich domain. In NP, ADAMs and ADAMTS regulate sperm-egg fusion, embryo implantation, trophoblast invasion, placental angiogenesis and spiral arteries remodeling through their ectodomain proteolysis of cell surface cytokines, cadherins and growth factors as well as their adhesion with integrins and cell-cell junction proteins. Preeclampsia (PE) is a serious complication of pregnancy characterized by new-onset hypertension (HTN) in pregnancy (HTN-Preg) at or after 20 weeks of gestation, with or without proteinuria. Insufficient trophoblast invasion of the uterine wall, inadequate expansive remodeling of the spiral arteries, reduced uteroplacental perfusion pressure, and placental ischemia/hypoxia are major initiating events in the pathogenesis of PE. Placental ischemia/hypoxia increase the release of reactive oxygen species (ROS), which lead to aberrant expression/activity of certain ADAMs and ADAMTS. In PE, abnormal expression/activity of specific ADAMs and ADAMTS that function as proteolytic sheddases could alter proangiogenic and growth factors, and promote the release of antiangiogenic factors and inflammatory cytokines into the placenta and maternal circulation leading to generalized inflammation, endothelial cell injury and HTN-Preg, renal injury and proteinuria, and further decreases in uteroplacental blood flow, exaggeration of placental ischemia, and consequently fetal growth restriction. Identifying the role of ADAMs and ADAMTS in NP and PE has led to a better understanding of the underlying molecular and vascular pathways, and advanced the potential for novel biomarkers for prediction and early detection, and new approaches for the management of PE.

[Relationship Between ABO Blood Group and Pregnancy Complications]

ABO blood group system is the most commonly used blood group classification system in clinic practice. The relevant antigens, A, B and H determinants, are complex carbohydrate molecules that are expressed in red blood cells and other cell lines and tissues. These antigens are determined by the ABO locus located on chromosome 9 (9q34.1-q34.2). ABO blood group is associated with the development of many human diseases, e.g., cardiovascular diseases, infectious diseases, and tumors. The relationship between the ABO blood group of pregnant women and various pregnancy complications, including preeclampsia (PE) and the related diseases, pregnancy associated venous thromboembolism (PA-VTE), gestational diabetes mellitus (GDM), and postpartum hemorrhage (PPH), have become the focus of obstetricians' recent research interest. Herein, we reviewed the relationship between ABO blood group and these pregnancy complications, and found that most of the reported findings supported the following views: 1) Blood type O is a protective factor for PE, while blood type AB increases the risk of PE; 2) blood types other than O are more prone to PA-VTE than blood type O; 3) blood type O or blood type AB may be related to the pathogenesis of GDM; 4) women of blood type O are at higher risks for PPH than those of other blood types. More in-depth epidemiological and genetic studies are needed to confirm these findings in the future. These findings can provide new ideas for researching into the pathogenesis of obstetric diseases and form the theoretical basis for obstetricians to prevent and treat related diseases.

Molecular Advances in Preeclampsia and HELLP Syndrome

Preeclampsia (PE) constitutes one of the principal reasons for maternal and perinatal morbidity and mortality worldwide. The circumstance typically implicates formerly healthful normotensive women, after 20 weeks of gestation, typically withinside the third trimester, without regarded threat elements or past deliveries. PE can be further complicated with hemolysis and thrombocytopenia, leading to the emergence of HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low platelets). Both conditions are classified as hypertensive diseases of pregnancy (HDP), and their pathogenesis has been linked to an excessive maternal inflammatory response, accompanied by enhanced endothelial activation. Several studies have found that in pregnancies affected by PE/HELLP, von Willebrand factor (vWF) antigen levels (vWF:Ag) are significantly elevated, while its cleaving protease (ADAMTS-13, A Disintegrin-like and Metalloprotease with Thrombospondin type 1 motif, member 13) activity is normal to decreased. Furthermore, the higher urine excretion of the terminal complement complex C5b-9, as well as its greater deposition in the placental surface in preeclamptic women, imply that the utero-placental unit’s distinctive deficits are intimately tied to disproportionate complement activation. The goal of this updated evaluation is to provide the most up-to-date molecular advances in the pathophysiology of PE/HELLP syndromes. Recent medical data on vWF:Ag levels in patients with PE, ADAMTS-13, and dysregulation of the complement system, are highlighted and evaluated. Furthermore, we discuss the relationship between those entities and the progression of the disease, as well as their significance in the diagnostic process. Finally, considering the difficulties in analyzing and controlling those symptoms in pregnant women, we can provide a current diagnostic and therapeutic algorithm.

rhADAMTS13 reduces oxidative stress by cleaving VWF in ischaemia/reperfusion-induced acute kidney injury

AIMS

Acute kidney injury (AKI), a major health burden, lacks effective therapy. Anti-inflammatory actions of a disintegrin and metalloproteinase with a thrombospondin type 1 motif member 13 (ADAMTS13) may provide a new treatment option for AKI. Along with inflammation, oxidative stress is critical for AKI development, yet the impact of ADAMTS13 on oxidative stress in AKI remains to be fully elucidated.

METHODS

We assess recombinant human ADAMTS13 (rhADAMTS13) actions on oxidative stress in a murine ischaemia/reperfusion (IR) model. Antioxidant stress-enzyme activities, renal morphology, kidney function markers and vascular function of isolated afferent arterioles are quantified.

RESULTS

rhADAMTS13 provided after IR, reduces blood urea nitrogen (BUN) by 33% and serum creatinine (Scr) by 73% in 24 hours post-IR. rhADAMTS13 reduces BUN (40.03 ± 20.34 mmol/L vs 72.35 ± 18.74 mmol/L, P < .01), Scr (75.67 ± 51.19 μmol/L vs 176.17 ± 55.38 μmol/L, P < .01) and proteinuria by 41% in 48 hours post-IR as well. Moreover, rhADAMTS13 administration decreases malondialdehyde (MDA) and increases the activity of antioxidant stress enzymes, and attenuates reactive oxygen species production. rhADAMTS13 also upregulates nuclear factor-erythroid-2-related factor 2/haem oxygenase-1, enhances antioxidant enzymes activity and alleviates endothelial dysfunction. Finally, treatment with rhADAMTS13 mitigates severe functional and morphological injury present in IR mice. Extracellular signal-regulated kinase (ERK) phosphorylation is limited by rhADAMTS13 and PPARγ expression is partly restored in ischaemic kidneys. Co-administration of von Willebrand factor (VWF) impairs rhADAMTS13's antioxidant capacity and its protective role in IR.

CONCLUSION

rhADAMTS13 alleviates renal IR injury through antioxidant effects by cleaving VWF.

Unfolding the pathophysiology of congenital thrombotic thrombocytopenic purpura in pregnancy: lessons from a cluster of familial cases

BACKGROUND

Thrombotic thrombocytopenic purpura (TTP), a rare, potentially life-threatening thrombotic microangiopathy, manifests either as congenital TTP or acquired forms. It is caused by the absence or severe depletion of a disintegrin and metalloproteinase with thrombospondin motifs 13 (ADAMTS13) protease, leading to the accumulation of ultra large von Willebrand factor multimers as well as extensive platelet adhesion and clumping, which can ultimately cause severe secondary end-organ damage. Pregnancy can provoke or exacerbate TTP, leading to maternal and fetal complications.

OBJECTIVE

In this report, we focused on pregnancy outcomes in a recently recognized cohort of congenital TTP patients of Bedouin Arab descent in southern Israel who were all homozygous for a novel c.3772delA variant of the ADAMTS13 gene, leading to the clinical manifestations of TTP largely during pregnancy.

STUDY DESIGN

All patients presented in this study belong to 2 closely related families of Arab Bedouin descent and were found to be homozygous for a novel ADAMTS13-c.3772delA variant. The cohort consisted of 19 females; 16 of them had congenital TTP and had been pregnant and were thus included. Patient data were collected from electronic medical records.

RESULTS

Of note, 13 women from our cohort, who delivered 14 fetuses (owing to 1 twin pregnancy), were diagnosed with congenital TTP following complicated pregnancies, which included recurrent pregnancy loss, stillbirth, early onset preeclampsia (both mild and severe), hemolysis, elevated liver enzymes and low platelet count syndrome, intrauterine growth restriction with abnormal Doppler flow, preterm premature rupture of membranes, and a total perinatal mortality rate of 30.7% (4/13). An additional 3 women, who were diagnosed owing to complications outside of pregnancy and at older ages, experienced TTP during their pregnancies, which occurred before diagnosis. Subsequent pregnancies were treated with fresh frozen plasma leading to a 100% fetal survival rate in the pregnancies that reached fetal viability. All placentas had lesions consistent with maternal vascular underperfusion. However, the severity and frequency of these lesions were lower in the 8 placentas from pregnancies treated with fresh frozen plasma.

CONCLUSION

This case series details a distinctive cohort of congenital TTP patients, all homozygous for the same, novel ADAMTS13 variant, who presented with clinical complications during pregnancy and maternal vascular lesions of underperfusion in the placenta. Our findings imply that the variant identified in the ADAMTS13 gene in our cohort may have a specific functional impact on the placenta, and that treatment with fresh frozen plasma during pregnancy ameliorates the course of the disease, leading to a milder phenotype or a normal pregnancy in the majority of cases.

Early ADAMTS13 testing associates with pre-eclampsia occurrence in antiphospholipid syndrome

INTRODUCTION

Women with obstetric antiphospholipid syndrome (oAPS) still develop placental diseases, mainly pre-eclampsia (PEcl), which diagnosis is associated with reduced ADAMTS13 levels. Testing ADAMTS13 in newly pregnant oAPS may provide evidence for risk stratification.

MATERIALS AND METHODS

We retrospectively investigated the prognostic value of ADAMTS13 activity, antigen and antibodies on stored plasma samples obtained prior to beginning low-molecular weight heparin-low dose aspirin treatment in 513 oAPS women.

RESULTS

Some women had evidences of early positive ADAMTS13 antibodies and low ADAMTS13 activity:antigen ratio, suggestive of ADAMTS13 dysfunction. Women with a subsequent PEcl had higher ADAMTS13 antibodies (p < 0.0001), and lower ADAMTS13 activity and activity:antigen ratios (p < 0.0001). In multivariate analysis, these markers were significant risk factors for PEcl and for the most devastating PEcl subgroups (early-onset PEcl, severe PEcl, PEcl with no living child after 28 days). ADAMTS13-related markers showed acceptable discrimination power to predict clinical events, particularly for ADAMTS13 activity:antigen ratio in predicting PEcl cases with no living child after 28 days (AUC: 0.844 (0.712-0.974), p < 0.0001), with excellent negative predictive value (0.990).

CONCLUSIONS

The characterization of ADAMTS13 in newly pregnant women with oAPS depicts the risk of PEcl occurrence. ADAMTS13 might help identify pregnant women with oAPS not requiring escalating treatment strategies to prevent PEcl.

Biological potentials for a family of disintegrin and metalloproteinase (ADAMDEC)-1 in mouse normal pregnancy

Our previous research has indicated local expression of ADAMDEC-1, a family of disintegrin and metalloproteinase, was confirmed in the mouse placentas and enhancement was found in the sites for spontaneous abortion. Present study was aimed to identify biological effects of ADAMDEC-1 in pregnancy process. Syngeneic pairs of C57BL/6J mice and heterogenic mating pairs of CBA/J and DBA/2 mice were used. Pregnant mice were treated with recombinant ADAMDEC-1 protein. Vasculogenesis effects was evaluated using the Matrigel plugs including vascular endothelial growth factor singularity or combination with ADAMDEC-1. ADAMDEC-1 single effects were evaluated by tubal formation and proliferation assays using HuEht-1 endothelial cells. Expression of ADAMDEC-1 was not exactly corresponded with the time periods for miscarriage initiation. ADAMDEC-1 was distributed in normal placentas and fetuses, especially at extraembryonic ectoderm, decidua cells, uterine natural killer (uNK) cells in decidua, trophoblasts in labyrinthine zone, and hematopoietic cells in umbilical blood and fetal liver. ADAMDEC-1 treatment did not affect reproductive performances, while it elevated uNK cell recruitment in placenta and enlarged lumen sizes of the intraplacental vessels. In vitro analysis also indicated ADAMDEC-1 promoting effect on tubal formation and cell length of HuEht-1. qPCR analysis showed that ADAMDEC-1 modified placental gene expression especially for linkage of actin filament rearrangement. Our findings suggested that ADAMDEC-1 is correlated on cell shape, stability, and movement via modification of actin cytoskeleton. ADMADEC-1 suspected to regulate cellular activity of endothelial cells, trophoblasts, and uNK cells and may support normal developing of mouse placentas.

Association of ABO blood groups with ovarian reserve, and outcomes after assisted reproductive technology: systematic review and meta-analyses

BACKGROUND

There has been an interest in the relationship between ABO blood groups and infertility. Many studies have investigated the association of ABO blood groups with diminished ovarian reserve (DOR), ovarian hyperstimulation syndrome (OHSS), and outcomes of assisted reproductive technology (ART), with controversial results.

METHODS

A systematic review and meta-analysis was conducted to evaluating the association of ABO blood groups with DOR, OHSS, and outcomes of ART.

RESULTS

Thirteen studies performed between 2010 and 2018 were included in this meta-analysis. DOR, OHSS, live birth rate (LBR), clinical pregnancy rate (CPR), miscarriage rate (MR) were reported in 9, 2, 4, 3, 2 studies, respectively. The combined results showed similar risk of DOR among individuals with blood group A (RR, 0.98; 95% confidence interval [CI], 0.85, 1.13), B (RR, 0.96; 95% CI, 0.76, 1.20), AB (RR, 1.00; 95% CI, 0.76, 1.30), and non-O (RR, 0.94; 95% CI, 0.79, 1.11) as compared to those with blood group O. Meta-analysis showed that the incidences of OHSS were similar in women with blood group A (RR, 1.05; 95% CI, 0.66, 1.66), B (RR, 1.04; 95% CI, 0.46, 2.35), AB (RR, 0.51; 95% CI, 0.10, 2.56), non-O (RR, 1.02; 95% CI, 0.65, 1.57) with blood group O. As to the clinical outcomes, meta-analysis showed no difference in LBR among individuals with blood group A (RR, 1.27; 95% CI, 0.74, 2.17), B (RR, 1.47; 95% CI, 0.95, 2.29), AB (RR, 1.48; 95% CI, 0.76, 2.90), non-O (RR, 1.28; 95% CI, 0.83, 1.98) when compared to those with blood group O. Similarly, the results also found that there were no difference in CPR and MR between women with blood A (CPR: RR, 1.12), B (CPR: RR, 1.08), AB (CPR: RR, 1.05), non-O (CPR: RR, 1.05; MR: RR, 0.94) and blood group O.

CONCLUSIONS

ABO blood groups may not be associated with DOR, OHSS, LBR, CPR, and MR of ART. Infertility and ART outcomes are influenced by multiple factors. Blood groups should not be taken into account excessively during diagnosis and treatment of infertile women.

Hypomethylation of DNA promoter upregulates ADAMTS7 and contributes to HTR-8/SVneo and JEG-3 cells abnormalities in pre-eclampsia

INTRODUCTION

Accumulating evidences have suggested a crucial role of epigenetics in the initiation and progression of pre-eclampsia (PE). Here, we studied the expression of the metalloproteinase ADAMTS7 and the methylation level of its promoter in PE placentas and investigated ADAMTS7 role in the pathogenesis of PE.

METHODS

We first explored ADAMTS7 expression in PE and normal placentas by reverse transcription quantitative PCR (RT-qPCR), western blot, and immunohistochemistry. Methylation specific PCR (MSP) and bisulfite sequencing PCR (BSP) were performed to evaluate the methylation status of ADAMTS7 promoter. Treatment with 5'-Aza was used to induce demethylation and thereby to explore the direct relationship between promoter methylation and ADAMTS7 expression. CCK8 assay, colony formation assay, and trans-well assay were conducted to assess the viability, migration, and invasion of HTR-8/SVneo and JEG-3 cells.

RESULTS

Our results showed that ADAMTS7 expression was upregulated in PE placentas. Methylation analysis revealed a hypomethylated status of ADAMTS7 promoter regions in PE placenta tissues. Besides, demethylation induced by 5'-Aza directly restored ADAMTS7 expression in trophoblast cells. Finally, overexpression of ADAMTS7 inhibited viability, migration, and invasion of HTR-8/SVneo and JEG-3 cells, while silence of ADAMTS7 by RNA interference reciprocally facilitated cell viability, migration and invasion in vitro.

DISCUSSION

Upregulation of ADAMTS7 by promoter hypomethylation in placenta might contribute to the etiology of PE via suppressing cell functions of trophoblasts.

Expression of ESRP1 at human fetomaternal interface and involvement in trophoblast migration and invasion

INTRODUCTION

Studies have reported that villous cytotrophoblasts (CTBs) undergo a partial epithelial to mesenchymal transition (EMT) when differentiating into extravillous cytotrophoblasts (EVTs). Epithelial splicing-regulatory protein 1 (ESRP1), an alternative splicing regulator, has been demonstrated to play important roles in the EMT process. Nevertheless, the roles of ESRP1 in the placentation remain undefined.

METHODS

ESRP1 expression in placental tissues throughout pregnancy was determined by immunohistochemistry and western blotting. The effect of ESRP1 knockdown by using small-interfering RNAs (siRNAs) on the phenotype of trophoblast cell line (HTR-8/SVneo) and villous explants was evaluated.

RESULTS

ESRP1 was localized within the CTBs, trophoblast columns, and EVTs located in the decidua. ESRP1 expression was changed during pregnancy, with the highest expression level in term placentae. ESRP1 knockdown significantly increased the migration and invasion of HTR-8/SVneo cells, as well as the outgrowth of EVTs from villous explants, without affecting cell proliferation. This enhanced effect was associated with the increased expression of N-cadherin, vimentin and CD44.

DISCUSSION

Our results suggested an important role for ESRP1 in regulating trophoblast migration and invasion during placentation.

Role of proteases in dysfunctional placental vascular remodelling in preeclampsia

Preeclampsia is a syndrome characterised by vascular dysfunction, impaired angiogenesis, and hypertension during pregnancy. Even when the precise pathophysiology of preeclampsia remains elusive, impaired vascular remodelling and placental angiogenesis in the placental villi and defective trophoblast invasion of the uterus are proposed as crucial mechanisms in this syndrome. Reduced trophoblast invasion leads to reduced uteroplacental blood flow and oxygen availability and increased oxidative stress. These phenomena trigger the release of soluble factors into the maternal and foetoplacental circulation that are responsible of the clinical features of preeclampsia. New blood vessels generation as well as vascular remodelling are mechanisms that require expression and activity of different proteases, including matrix metalloproteases, a-disintegrin and metalloproteases, and a-disintegrin and metalloprotease with thrombospondin motifs. These proteases exert proteolysis of the extracellular matrix. Additionally, cathepsins, a family of proteolytic enzymes, are primarily located in lysosomes but are also released by cells to the extracellular space. This review focuses on the role that these proteases play in the regulation of the uterine trophoblast invasion and the placental vascular remodelling associated with preeclampsia.

Non-O blood group and outcomes of in vitro fertilization

PURPOSE

Retrospective and cross-sectional studies suggested that non-O blood group may be associated with failures of in vitro fertilization (IVF), but data remain controversial. The aim of this observational cohort study was to prospectively evaluate the effect of non-O blood type on clinical outcomes of IVF.

METHODS

Women < 40 years who underwent IVF and had ABO blood type recorded as part of the routine workup were eligible. The primary study outcome was live birth. Secondary outcomes included spontaneous abortion, positive pregnancy test, and clinical pregnancy.

RESULTS

A total of 497 women with a mean age of 34.6 (standard deviation 3.2) years were included. The mean number of embryos transferred was 2.3 (standard deviation 0.6). The most common ABO blood types were O (n = 213, 42.9%) and A (n = 203, 40.8%), while 63 (12.7%) and 18 (3.6%) women had the B and AB blood types, respectively. Differences in live birth (21.8 vs. 24.3%, odds ratio [OR] 1.17; 95% confidence intervals [CI], 0.76 to 1.78), positive pregnancy test (37.9 vs. 36.6%, OR 0.96; 95% CI, 0.66 to 1.38), clinical pregnancy (35.1 vs. 33.8%, OR 0.95; 95% CI, 0.66 to 1.39), and spontaneous abortion (12.3 vs. 9.2%, OR 0.72; 95% CI, 0.41 to 1.29) between women with O and non-O blood type were not statistically significant.

CONCLUSIONS

In a prospective cohort study, we confirmed the lack of a significant association between non-O blood type and clinical outcomes of IVF. Further studies are needed to clarify whether non-O blood group has any prognostic relevance in women undergoing IVF.