Uteroplacental Interface Research Articles

Immunohistochemical examination of the utero-placental interface of cows on days 21, 31, 40, and 67 of gestation.

What we understand about early stages of placentation in cattle is based on an elegant series of electron microscopic images that provide exquisite detail, but limited appreciation for the microanatomy across the utero-placental interface. In order to achieve a global perspective on the histology of bovine placentation during critical early stages of gestation, i.e., days 21, 31, 40, and 67, we performed immunohistochemistry to detect cell-specific expression of pregnancy-associated glycoprotein (PAG), cytokeratin, epithelial (E)-cadherin, and serine hydroxymethyltransferase 2 (SHMT2) at the intact utero-placental interface. Key findings from the immunohistochemical analyses are that there are: (1) PAG-positive cells with a single nucleus within the uterine luminal epithelial (LE) cells; (2) PAG-positive cells with two nuclei in the LE; (3) PAG-positive syncytial cells with more than three nuclei in the LE; (4) LE cells that are dissociated from one another and dissociated from the basement membrane in regions of syncytialization within the LE layer; (5) replacement of the mononuclear LE with a multi-layer thick population of PAG-positive cells invading into the uterine stroma of caruncles, but not into the stroma of intercaruncular endometrium; and (6) PAG-, E-cadherin- and SHMT2-positive mononuclear cells at the leading edge of developing cotyledonary villi that eventually represent the majority of the epithelial surface separating caruncular stroma from cotyledonary stroma. Finally, the utero-placental interface of ruminants is not always uniform across a single cross-section of a site of placentation which allows different conclusions to be made depending on the part of the utero-placental interface being examined.

Management of pregnant women who have bleeding disorders.

Bleeding disorders, including von Willebrand disease (VWD), hemophilia, other coagulation factor deficiencies, platelet disorders, defects of fibrinolysis, and connective tissue disorders, have both maternal and fetal implications. Successful management of bleeding disorders in pregnant women requires not only an understanding of bleeding disorders but also an understanding of when and how bleeding occurs in pregnancy. Bleeding does not occur during a normal pregnancy with a healthy placenta. Bleeding occurs during pregnancy when there is an interruption of the normal utero-placental interface, during miscarriage, during an ectopic pregnancy, or at the time of placental separation at the conclusion of pregnancy. Although mild platelet defects may be more prevalent, the most commonly diagnosed bleeding disorder among women is VWD. Other bleeding disorders are less common, but hemophilia carriers are unique in that they are at risk of bleeding themselves and of giving birth to an affected male infant. General guidance for maternal management of a woman who is moderately or severely affected includes obtaining coagulation factor levels at a minimum in the third trimester; planning for delivery at a center with hemostasis expertise; and anticipating the need for hemostatic agents. General guidance for fetal management includes pre-pregnancy counseling; the option of preimplantation genetic testing for hemophilia; delivery at a tertiary care center with pediatric hematology and newborn intensive care; consideration of cesarean delivery of a potentially severely affected infant; and avoidance of invasive procedures such as scalp electrodes and operative vaginal delivery in any potentially affected infant.

CD39 abrogates platelet-derived factors induced IL-1β expression in the human placenta.

Tissue insults in response to inflammation, hypoxia and ischemia are accompanied by the release of ATP into the extracellular space. There, ATP modulates several pathological processes, including chemotaxis, inflammasome induction and platelet activation. ATP hydrolysis is significantly enhanced in human pregnancy, suggesting that increased conversion of extracellular ATP is an important anti-inflammatory process in preventing exaggerated inflammation, platelet activation and hemostasis in gestation. Extracellular ATP is converted into AMP, and subsequently into adenosine by the two major nucleotide-metabolizing enzymes CD39 and CD73. Here, we aimed to elucidate developmental changes of placental CD39 and CD73 over gestation, compared their expression in placental tissue from patients with preeclampsia and healthy controls, and analyzed their regulation in response to platelet-derived factors and different oxygen conditions in placental explants as well as the trophoblast cell line BeWo. Linear regression analysis showed a significant increase in placental CD39 expression, while at the same time CD73 levels declined at term of pregnancy. Neither maternal smoking during first trimester, fetal sex, maternal age, nor maternal BMI revealed any effects on placental CD39 and CD73 expression. Immunohistochemistry detected both, CD39 and CD73, predominantly in the syncytiotrophoblast layer. Placental CD39 and CD73 expression were significantly increased in pregnancies complicated with preeclampsia, when compared to controls. Cultivation of placental explants under different oxygen conditions had no effect on the ectonucleotidases, whereas presence of platelet releasate from pregnant women led to deregulated CD39 expression. Overexpression of recombinant human CD39 in BeWo cells decreased extracellular ATP levels after culture in presence of platelet-derived factors. Moreover, platelet-derived factors-induced upregulation of the pro-inflammatory cytokine, interleukin-1β, was abolished by CD39 overexpression. Our study shows that placental CD39 is upregulated in preeclampsia, suggesting an increasing demand for extracellular ATP hydrolysis at the utero-placental interface. Increased placental CD39 in response to platelet-derived factors may lead to enhanced conversion of extracellular ATP levels, which in turn could represent an important anti-coagulant defense mechanism of the placenta.

Dilemmas in establishing preterm enteral feeding: where do we start and how fast do we go?

Beginning and achieving full enteral nutrition is a key step in the care of preterm infants, particularly very low birth weight (VLBW) infants. As is true for many organ system-specific complications of prematurity, the gastrointestinal tract must complete in utero development ex utero while concurrently serving a physiologic role reserved for after completion of full term development. The preterm gut must assume the placental function of the interface between a source of energy, precursors for anabolism, and micronutrients, and the developing infant-through digestion and absorption of milk, instead of directly from the mother via the uteroplacental interface. The benefits of enteral nourishment in preterm infants are counterbalanced by gastrointestinal complications of prematurity: dysmotility leading to difficulty establishing and advancing feeds, and the risk of necrotizing enterocolitis (NEC). Concern for these complications can prolong the need for parenteral nutrition with an associated increase in risk for central line-associated bloodstream infection (CLABSI) and parenteral nutrition (PN)-associated cholestasis or liver disease (PNALD). Thus, a daily issue facing neonatologists caring for preterm infants is how to optimally begin, advance, and reach full enteral nutrition sufficient to satisfy the nutrient, energy, and fluid requirements of VLBW infants while minimizing risk. In this perspective, we provide an overview of the approaches and supporting data for starting and advancing enteral feeds in preterm infants, particularly very low birth weight infants, and we discuss the significant gaps in knowledge that accompany current approaches. This framework recognizes the dilemmas of preterm feeding initiation andadvancement and identifies areas of opportunity for further investigation.

Ultrasonography of the Explanted Uterus in Placenta Accreta Spectrum: Correlation With Intraoperative Findings and Gross Pathology.

To better understand placenta accreta spectrum (PAS) by correlating postoperative ultrasonographic findings of the explanted uteroplacental interface with intraoperative findings and gross pathology. We enrolled consecutive pregnant patients aged 18 years and older with a prior cesarean delivery and antenatal diagnosis of lower uterine segment PAS who planned to undergo hysterectomy into this prospective, descriptive study. All underwent cesarean hysterectomy with standardized intraoperative photography. Ultrasonography of explanted postsurgical uteruses was performed by expert radiologists to obtain standard detailed images of the myometrial-placental interface and other areas of interest. Sagittal views of the gross pathologic specimen were photographed. We correlated the intraoperative, ultrasonographic, and gross pathologic findings as a study team and report four consistent patterns that emerged from this systematic evaluation. Thirty-four consecutive eligible patients were enrolled. The following consistent observations emerged: 1) The uteroplacental interface in the explanted specimen was smooth and distinct. At the point of maximal placental protrusion, the myometrium was imperceptible, but the placenta was confined by a smooth thin echogenic line of uterine serosa (the scar shell) unless surgically disrupted. 2) Every specimen of PAS grade 2-3 showed placenta bulging through the lower uterine segment in the region of prior hysterotomy. 3) Placentas extended to, but not through, the uterovesical interface or scar shell. Dense adhesive disease was found between the placenta and bladder. There were no cases of true bladder invasion. 4) Placental extension beyond the serosa (invasion) has a distinct appearance on postoperative ultrasonography with irregular frond-like protrusion of placental tissue. This appearance was always the result of surgical manipulation and was not present before delivery of the neonate. These findings suggest that PAS severity is likely mediated by progressive scar dehiscence and uterine remodeling, not placental invasion. This challenges the existence of in situ invasive percreta as it is currently described.

Failure of Placental Detachment in Accreta Placentation is Associated With Excessive Fibrinoid Deposition at the Utero-placental Interface

(Am J Obstet Gynecol. 2022;226:243.e1–10) Since placenta accreta was first described in 1937, the condition has been diagnosed by the direct attachment of villous tissue to the superficial myometrium or adjacent fibers without interposing decidua. There has been a lack of histopathologic studies investigating placenta accreta spectrum (PAS) disorders. This study aimed to evaluate the microscopic changes used to determine the grade of PAS and identify possible explanations of the abnormal placental tissue attachment in patients with scars from previous cesarean delivery.

Transcriptomic mapping of the metzincin landscape in human trophoblasts

The metzincin family of metalloproteases coordinates tissue developmental processes through regulation of growth factor availability, receptor signaling, and cell-cell/cell-matrix adhesion. While roles for select metzincins in controlling trophoblast functions in human placental development have been described, a comprehensive understanding of metzincin dynamics during trophoblast differentiation is lacking. To address this knowledge gap, single cell transcriptomic datasets derived from first trimester chorionic villi and decidua were used to decipher metzincin expression profiles and kinetics in diverse cell types within the utero-placental interface. Further, specific protease-substrate interactions within progenitor trophoblasts were examined to better define the progenitor niche. Within the uterine-placental compartment, 43 metzincin proteases were expressed across 15 cell-type clusters. Metzincin subgroups expressed in placental trophoblasts, placental mesenchymal cells, uterine stromal, and immune cells included multiple matrix metalloproteases (MMPs), a disintegrin and metalloproteases (ADAMs), a disintegrin and metalloproteases with thrombospondin repeats (ADAMTSs), pappalysins, and astacins. Within the trophoblast compartment, eight distinct trophoblasts states were identified: four cytotrophoblast (CTB), one syncytiotrophoblast precursor (SCTp), two column CTB (cCTB), and one extravillous trophoblast (EVT). Within these states 7 MMP, 8 ADAM, 4 ADAMTS, 2 pappalysin, and 3 astacin proteases were expressed. Cell trajectory modeling shows that expression of most (19/24) metzincins increase during EVT differentiation, though expression of select metalloproteases increase along the villous pathway. Eleven metzincins (ADAM10, -17, MMP14, -15, -19, -23B, ADAMTS1, -6, -19, TLL-1, -2) showed enrichment within CTB progenitors, and analysis of metzincin-substrate interactions identified ∼150 substrates and binding partners, including FBN2 as an ADAMTS6-specific substrate. Together, this work characterizes the metzincin landscape in human first trimester trophoblasts and establishes insight into the roles specific proteases perform within distinct trophoblast niches and across trophoblast differentiation. This resource serves as a guide for future investigations into the roles of metzincin proteases in human placental development.

Separation sign: novel ultrasound sign for ruling out diagnosis of placenta accreta spectrum.

ABSTRACTObjectiveTo assess the performance of the ‘separation sign’ as a predictor of normal placental separation in a large cohort of women at risk for placenta accreta spectrum (PAS) and in a high‐risk subgroup with placenta previa or anterior low‐lying placenta and at least one previous Cesarean delivery.MethodsThis was a prospective study of women at risk for PAS referred to a specialist clinic at between 22 and 38 weeks' gestation. All women underwent ultrasound assessment for the presence of the separation sign, which detects the difference in elasticity between the myometrium and the placenta, characterized by different rates of rebound after an ultrasound probe is used to apply pressure over the uteroplacental interface. When the sign is positive, the placenta appears to move relative to the myometrium, leading to the appearance or enhancement of the clear zone. The predictive performance of the separation sign for normal spontaneous placental separation at delivery was assessed.ResultsOf the 194 included women, 163 had a positive separation sign, all of whom went on to have normal placental separation at delivery. Of the 24 women with a negative separation sign, three (12.5%) had normal placental separation and 21 (87.5%) were diagnosed with PAS. This yielded a sensitivity of 98.2% (95% CI, 94.8–99.6%) and specificity of 100% (95% CI, 83.9–100%). In the high‐risk cohort (n = 35), a positive separation sign remained a reliable predictor of normal placental separation, with a positive predictive value of 100%, sensitivity of 88.9% (95% CI, 65.3–98.6%) and specificity of 100% (95% CI, 80.5–100%).ConclusionsThe separation sign could be a useful tool in women considered to be at risk for PAS, as it can facilitate the prediction of normal placental separation at delivery. This may prevent overtreatment, the associated iatrogenic morbidity and unnecessary allocation of clinical resources. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Significance of Placental Mesenchymal Stem Cell in Placenta Development and Implications for Preeclampsia.

The well-developed placentation is fundamental for the reproductive pregnancy while the defective placental development is the pathogenetic basis of preeclampsia (PE), a dangerous complication of pregnancy comprising the leading causes of maternal and perinatal morbidity and mortality. Placenta-derived mesenchymal stem cells (PMSCs) are a group of multipotent stem cells that own a potent capacity of differentiating into constitutive cells of vessel walls. Additionally, with the paracrine secretion of various factors, PMSCs inextricably link and interact with other component cells in the placenta, collectively improving the placental vasculature, uterine spiral artery remolding, and uteroplacental interface immunoregulation. Recent studies have further indicated that preeclamptic PMSCs, closely implicated in the abnormal crosstalk between other ambient cells, disturb the homeostasis and development in the placenta. Nevertheless, PMSCs transplantation or PMSCs exosome therapies tend to improve the placental vascular network and trophoblastic functions in the PE model, suggesting PMSCs may be a novel and putative therapeutic strategy for PE. Herein, we provide an overview of the multifaceted contributions of PMSCs in early placental development. Thereinto, the intensive interactions between PMSCs and other component cells in the placenta were particularly highlighted and further extended to the implications in the pathogenesis and therapeutic strategies of PE.

First-trimester ultrasound diagnostic features of placenta accreta spectrum in low-implantation pregnancy.

Low-implantation pregnancy (LIP) is an important marker for the diagnosis of placenta accreta spectrum (PAS) in the first trimester. Many grayscale and color Doppler ultrasound markers of PAS have been defined in the second and third trimesters of pregnancy, but have not been studied in the first trimester. The aim of this study was to determine whether PAS sonographic markers could be used in the first trimester to differentiate patients with LIP who develop PAS from those who do not. This was a retrospective case-control study of women who delivered at our institution between 2009 and 2019. Cases were women with PAS who delivered by Cesarean hysterectomy and who had undergone first-trimester ultrasound demonstrating LIP. Controls were women with persistent placenta previa without PAS who delivered by Cesarean section without postpartum hemorrhage and who had undergone first-trimester ultrasound demonstrating LIP. Sonographic images were reviewed by an investigator blinded to pregnancy outcome and ultrasound reports. Images were reviewed for presence of abnormal uteroplacental interface, increased lower uterine segment hypervascularity and placental lacunae, with or without swirling on grayscale or color Doppler ultrasound. Following review of the electronic health records, 21 cases and 46 controls met the inclusion criteria. Placental lacunae were present in 18/21 (85.7%) cases and 7/46 (15.2%) controls (odds ratio (OR), 33.4; 95% CI, 7.7-144.4; P < 0.001). The number of lacunae was significantly higher in cases compared with controls, with a median of five lacunae present in cases compared with a median of one lacuna in controls (P < 0.001). The median size of the lacunae was also significantly larger in cases compared with controls, measuring 10.03 (interquartile range (IQR), 7.3-12.05) mm and 4.15 (IQR, 4.05-5.05) mm, respectively (P = 0.001). Lacunae swirling on grayscale or color Doppler ultrasound was noted only in PAS cases, with 10/12 (83.3%) having swirling on grayscale ultrasound and 12/12 (100%) having swirling on color Doppler (P < 0.001). Presence of an abnormal uteroplacental interface was also observed only in PAS cases, at a rate of 17/20 (85.0%) (P < 0.001). Lower uterine segment (uterovesical, subplacental and/or intraplacental) hypervascularity was present in 14/14 (100%) cases and only 1/12 (8.3%) controls (P < 0.001). In women at risk of PAS, ultrasound markers of PAS can and should be assessed as early as in the first trimester. The use of a first-trimester prenatal ultrasound screening protocol and standardized approach to ultrasound examination in at-risk mothers may help increase detection of PAS and enable planning for optimal management of affected pregnancies. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Failure of placental detachment in accreta placentation is associated with excessive fibrinoid deposition at the utero-placental interface

The main histopathologic diagnostic criteria for the diagnosis of placenta accreta for more than 80 years has been the finding of a direct attachment of the villous tissue to the superficial myometrium or adjacent to myometrial fibers without interposing decidua. There have been very few detailed histopathologic studies in pregnancies complicated by placenta accreta spectrum disorders and our understanding of the pathophysiology of the condition remains limited. To prospectively evaluate the microscopic changes used in grading and to identify changes that might explain the abnormal placental tissue attachment. A total of 40 consecutive cesarean delivery hysterectomy specimens for placenta previa accreta at 32 to 37 weeks of gestation with at least 1 histologic slide showing deeply implanted villi were analyzed. Prenatal ultrasound examination included placental location, myometrial thickness, subplacental vascularity and lacunae. Macroscopic changes of the lower segment were recorded during surgery and areas of abnormal placental adherence were sampled for histology. In addition, 7 hysterectomy specimens with placenta in-situ from the Boyd Collection at 20.5 to 32.5 weeks were used as controls. All 40 patients had a history of at least 2 previous cesarean deliveries and presented with a mainly anterior placenta previa. Of note, 37 (92.5%) cases presented with increased subplacental vascularity, 31 (77.5%) cases with myometrial thinning and all with lacunae. Furthermore, 20 (50%) cases presented with subplacental hypervascularity, lacunae score of >3, and lacunae feeder vessels. Intraoperative findings included anterior lower segment wall increased vascularization in 36 (90.0%) cases and extended area of dehiscence in 18 (45.0%) cases. Immediate gross examination of hysterectomy specimens showed an abnormally attached areas involving up to 30% of the basal plate, starting at <2 cm from the dehiscence area in all cases. Histologic examination found deeply implanted villi in 86 (53.8%) samples with only 17 (10.6%) samples presenting with villous tissue reaching at least half the uterine wall thickness. There were no villi crossing the entire thickness of the uterine wall. There was microscopic evidence of myometrial scarification in all cases. Dense fibrinoid deposits, 0.5 to 2 mm thick, were found at the utero-placental interface in 119 (74.4%) of the 160 samples between the anchoring villi and the underlying uterine wall at the accreta areas and around all deeply implanted villi. In the control group, the Nitabuch stria and basal plate became discontinuous with advancing gestation and there was no evidence of fibrinoid deposition at these sites. Samples from accreta areas at delivery present with a thick fibrinoid deposition at the utero-placental interface on microscopic examination independently of deeply implanted villous tissue in the sample. These changes are associated with distortion of the Nitabuch membrane and might explain the loss of parts of the physiological site of detachment of the placenta from the uterine wall in placenta accreta spectrum. These findings indicate that accreta placentation is more than direct attachment of the villous tissue to the superficial myometrium and support the concept that accreta villous tissue is not truly invasive.

HMGB1 regulates lipopolysaccharide-induced cellular dysfunction in HTR8/SVneo cells: Implications for the role of HMGB1 in unexplained spontaneous miscarriage

IntroductionApproximately half of miscarriages are of an unknown aetiology and are likely characterized by aberrant inflammation at the uteroplacental interface. High mobility group box 1 (HMGB1) is a ubiquitous nuclear protein that participates in the pathological inflammatory response. The present study investigated the role of HMGB1 in inflammation-induced damage in trophoblasts and elucidated the underlying mechanism. MethodsImmunohistochemistry, qRT-PCR and Western blotting were used to detect the expression of HMGB1 in early unexplained miscarriage and normal placentas. Lipopolysaccharide (LPS)-induced HTR8/SVneo cells were used as an in vitro model to mimic the aberrant inflammation at the uteroplacental interface of miscarriage. The expression of HMGB1 and the autophagy-related proteins LC3 and Beclin1 was detected using Western blotting. Autophagy was studied in villous tissues using immunofluorescence and Western blotting. Cell proliferation and migration were analysed. ResultsThe expression level of HMGB1 in villous tissues with early unexplained miscarriage was significantly higher than the normal pregnancy group. The inhibition of HMGB1 in LPS-treated HTR8/SVneo cells decreased the expression of Beclin 1 and LC3, which promoted cell proliferation and migration. We found a high level of autophagy in miscarriage placentas. HMGB1 and autophagy inhibition reversed the proliferation and migration of LPS-induced HTR-8/SVneo cells. DiscussionOur results demonstrated that HMGB1 participated in LPS-induced inflammation via autophagy and regulated trophoblast functions, such as cell proliferation and migration, to potentially participate in the pathogenesis of miscarriage.

Kisspeptin/Receptor Dysregulation during Early Gestation in the BPH/5 Mouse, A Model of Preeclampsia

Preeclampsia (PE) is a hypertensive disorder of pregnancy with an incompletely understood etiology affecting approximately 10% of pregnancies worldwide. Obesity is a risk factor among women that develop PE and is mirrored in the blood pressure high subline 5 (BPH/5) mouse. Before pregnancy, BPH/5 adult females are hyperphagic, obese and dyslipidemic with increased reproductive white adipose tissue (rWAT) that expands throughout pregnancy, along with other PE-like symptoms. Pregnant BPH/5 females develop poor placentation with decreased trophoblast invasion and inadequately remodeled decidual vessels, a recognized feature of PE. Kisspeptins (KP), a family of small peptides encoded by the Kiss1 gene, are important regulators of cellular migration and proliferation. They have been shown to inhibit the migration and invasion of trophoblast cells in humans and rodents and may be involved in abnormal placentation observed in PE. Interestingly, Kiss1/Kiss1r are also expressed in the adipose tissue with a potential role in metabolism regulation, including inhibition of adipogenesis and lipolysis induction. When fed a normal diet, adult female kiss1r-knockout mice have reduced energy expenditure, increased adiposity and body weight (BW) than wild-type littermates. Hence, we aimed to characterize Kiss1/Kiss1r mRNA expressionin BPH/5 rWAT and the uteroplacental interface at the peak of decidualization. We hypothesized that at embryonic day (e) 7.5, Kiss1/Kiss1r will be higher in BPH/5 implantation sites, but lower in the rWAT, when compared to control C57. Furthermore, we hypothesized that feeding BPH/5 dams a 25% calorie restriction (CR) diet, beginning at conception (e0.5), would normalize the Kiss1/Kiss1r in e7.5 implantation sites and rWAT. To test our hypothesis, implantation sites and rWAT were collected at e7.5 from adult BPH/5 and C57 fed ad libitum, and age-matched e7.5 BPH/5 females after 25% CR from e0.5 to e7.5 (n = 5-9/group). Kiss1/Kiss1r were measured using RT-PCR and comparisons were performed using independent samples t-test (SPSS) with significance set at 5%. BPH/5 e7.5 implantation sites had 2-fold higher Kiss1/Kiss1r when compared to C57 (p < 0.05). In the rWAT, Kiss1 was approximately five-fold lower in BPH/5 vs. C57 (p < 0.05). When considering Kiss1r, however, the expression was 1.5-fold higher in BPH/5 vs. C57 (p < 0.05). When comparing ad libitum BPH/5 and 25% CR BPH/5 females at e7.5, there was no difference in the rWAT Kiss1/Kiss1r (p > 0.05). Therefore, upregulation of Kiss1/Kiss1r at the utero-placental interface during the peak of decidualization, along with increased Kiss1r in the rWAT characterizes the BPH/5 model of PE. Concurrently, the Kiss1 levels are lower in the BPH/5 rWAT at e7.5 and may be associated with the increased adiposity of these mice previously shown throughout gestation. Even though 7 days of 25% CR has been previously shown to decrease the body weight of pregnant BPH/5 females, it did not alter the expression levels of Kiss1/Kiss1r in the rWAT at e7.5. Further studies are necessary to investigate KP expression in the adipose tissue of CR BPH/5 females at later timepoints of gestation and their role in placental development in PE.

PFKFB3 regulates lipopolysaccharide-induced excessive inflammation and cellular dysfunction in HTR-8/Svneo cells: Implications for the role of PFKFB3 in preeclampsia

IntroductionPreeclampsia is characterized by overactive inflammation at the uteroplacental interface, leading to trophoblasts dysfunction. 6-phosphofructo-2-kinase/fructose-2, 6-bisphosphatase 3 (PFKFB3) is a crucial glycolytic regulator which has recently been found to participate in the pathological inflammatory states. This study aimed to investigate the role of PFKFB3 in the inflammation-induced damage in trophoblasts, and elucidate the underlying mechanisms. MethodsImmunohistochemistry, qRT-PCR, and Western blot analysis (WB) were used to detect the expression of PFKFB3 in preeclamptic and normal placentas. Lipopolysaccharide (LPS)-induced HTR8/SVneo cells were established as the in vitro model to simulate the overactive inflammation at the uteroplacental interface of PE, which were subsequently transfected with PFKFB3 siRNA. The expression of PFKFB3, NF-κB-p-p65, phosphorylation states of NF-κB-p65, ICAM-1, Bcl-2, BAX, and MMP2 were detected by WB. qRT-PCR was used to detect the expression of TNF-α and IL-1β. The ICAM-1 expression was also reflected by monocyte adhesion assay. Reactive Oxygen Species (ROS) levels were detected by DCFH-DA (2,7-Dichlorodi-hydrofluorescein diacetate). Apoptosis was detected using Annexin V-FITC staining. Migration and invasion were measured by wound-healing and transwell assays. ResultsPFKFB3 was up-regulated in the preeclamptic placenta. In LPS-treated HTR-8/Svneo cells, the inhibition of PFKFB3 blocked the NF-κB signal pathway, thereby downregulating the expression of proinflammatory cytokines and adhesion molecules, meanwhile, PFKFB3 knockdown significantly alleviated monocyte adhesion, oxidative stress, apoptosis, and reinstated migration and invasive capacity. DiscussionPFKFB3 controls the LPS-induced inflammation via the NF-κB pathway and impacts trophoblasts function such as adhesion, oxidative stress, apoptosis, migration, and invasion, thereby potentially participating in the preeclamptic etiopathogenesis.

172 Accuracy of ultrasound diagnosis of placenta accreta during the first trimester

Low gestational sac implantation (LGSI) is an important marker for the diagnosis of placenta accreta spectrum (PAS) in the first trimester. Pregnancies with placenta previas but without PAS also have LGSI in early gestation. The objective of this study was to identify first trimester ultrasound markers to diagnose PAS in pregnancies with LGSI. This was a retrospective case-control study of pregnancies who delivered at our institution from 2009-2019. Cases represented pregnancies with PAS who delivered by cesarean-hysterectomy and had a first trimester ultrasound with LGSI. Controls represented pregnancies with persistent placenta previas without PAS, who delivered by cesarean-section without post-partum hemorrhage and had a first trimester ultrasound with LGSI. Sonographic images were reviewed by an investigator blinded to pregnancy outcome and sonography reports. Images were reviewed for presence of abnormal utero-placental interface, increased uterovesical hypervascularity, and placental lacunae, with or without swirling on gray scale or color Doppler. Definitions of ultrasound markers followed national task force on PAS. 21 cases and 46 controls met the inclusion criteria. Lacunae were present in 18/21 (85.7%) cases and in 7/46 (15.2%) controls (OR 33.4; 95% CI 7.7-144.4, p<.001). Presence of 3 or more lacunae were 100% predictive of PAS with an average of 5.0 lacunae in cases compared to 1.3 in controls (p=.019). The average size of the lacunae was 9.88±3.7mm in cases and 4.41±0.56 mm in controls (p<.001). Lacunae swirling on gray scale or color Doppler were 100% predictive of PAS (p<.001). Presence of an abnormal utero-placental interface was also 100% predictive of PAS (p<.001). Uterovesical hypervascularity was present in 14/14 cases and only 1/12 controls (p<.001). To our knowledge this is the first study evaluating the predictive value of PAS markers in early gestation in pregnancies with LGSI. In pregnancies with LGSI, presence of 3 or more lacunae or abnormal utero-placental interface in the first trimester is highly predictive of PAS.

Emerging Role of Prenatal Magnetic Resonance Imaging in the Diagnosis of Placental Adhesion Disorders and its Relation with Intraoperative Findings- A Cross-sectional Study

Introduction: Placental Adhesion Disorders (PADs) aka Placenta Accreta Spectrum (PAS) of disorders are a common cause of postpartum haemorrhage, which in turn is an avoidable cause of significant maternal morbidity and mortality. The exponential increase in the prevalence of PADs worldwide primarily ascribed to increasing percentage of caesarean section deliveries therefore contributes significantly to potentially life-threatening obstetrical emergencies. Accurate prenatal diagnosis of PAD is hence fundamental for patient management and prognostication. Imaging plays an indispensable role in the antenatal diagnosis of PAD thereby translating to improved maternal outcomes. Aim: To determine the diagnostic accuracy of prenatal Magnetic Resonance Imaging (MRI) in predicting abnormal invasive placentation and to associate MRI findings with intraoperative findings. Materials and Methods: The present cross-sectional study was conducted between March 2019 to March 2020. Pregnant females with clinically and/or sonographically suspected PAD and having major risk factors of PAD {Lower Segment Caesarean Section (LSCS) in previous and placenta previa in present gestation} were subjected to dedicated placenta protocol MRI examination. The placental morphology, localisation and adhesion suggestive features were evaluated in detail. Descriptive statistical analysis was done for final assessment. Results: A total of 27 study participants, with mean age of 28±2.15 years, showed MRI findings compatible with PAD. Placenta previa complete (66.67%); was the dominant subtype observed in the study. In terms of degree of invasion, placenta accreta in 44.44% (n=12) was predominantly observed on preliminary MRI based assessment. The most reliable MRI features predictive of placental invasion in the present study (seen in 100% cases of PAD) included T2 dark intraplacental bands, heterogenous intraplacental signal intensity, disorganised intraplacental vascularity, myometrial thinning, loss of the uteroplacental interface and maternal neovascularity. In one case, MRI erroneously over-diagnosed increta as percreta. The overall diagnostic performance of these MRI parameters was with sensitivity, specificity, Positive Predictive Value (PPV) and Negative Predictive Value (NPV) of 100%, 95%; 87.5% and 100% in those with placenta percreta compared to 94.12%, 100.00%, 100% and 95% for the placenta accreta or increta cases, respectively. Conclusion: MRI has high diagnostic accuracy in detection of PADs among the high-risk patients. Dedicated placenta protocol prenatal MRI should hence be incorporated in diagnostic work- up of all high-risk patients of PAD for reaping benefits of timely management, planning and saving lives.

Ultrasound-histopathologic features of the utero-placental interface in placenta accreta spectrum

IntroductionThe objective of this study was to evaluate the relationship between utero-placental vascular changes on ultrasound imaging and histopathologic findings according to the grade of villous invasion in placenta accreta spectrum (PAS). MethodsThe ultrasound features of 31 patients with singleton pregnancies diagnosed prenatally with low-lying/placenta previa accreta were compared with histopathology findings following caesarean hysterectomy (n = 25) or partial myometrial resection (n = 6). The number and degree of transformation of arteries within the superficial layer of myometrium were recorded. Cytokeratin 7 (CK7) immunohistochemistry was used to complement H&E analysis. ResultsAll 31 patients presented with loss of clear zone, myometrial thinning and placenta lacunae. Subplacental hypervascularity and lacunae feeder vessels were found in 25 and nine cases, respectively. Large recent intervillous thromboses were found in one case with adherent villi and 12 cases with invasive villi, and showed a significantly different distribution according to lacunae scores. Thick basal plate fibrinoid deposits were found in all the areas of abnormally adherent and invasive villous tissue There was no significant difference in the mean count of partially remodeled vessels or vessels completely lacking remodeling according to the lacunae score and grade of placental invasiveness. EVT cells were arranged in superficial confluent sheets or superficial irregular clusters, or were scattered deep below the basal plate. ConclusionPlacental ultrasound and histopathologic features associated with PAS are more pronounced in invasive cases suggesting that they are secondary to the haemodynamic effects of abnormally deep placentation and transformation of the radial and arcuate arteries.

Suspected Placenta Accreta: Using Imaging to Stratify Risk of Morbidity.

This study was aimed to compare clinical outcomes and use of interventions in women with suspected accreta based on the degree of antenatal suspicion. This was a retrospective cohort study of women with suspected accreta from 2007 to 2019. Included patients had one or more imaging studies suggestive of accreta. Cases were classified as "lower risk" if imaging showed possible signs of accreta including mild or superficial myometrial infiltration, an abnormal uterine contour, an abnormal uteroplacental interface, or loss of the retroplacental hypoechoic zone and "higher risk" if there was clear evidence of more than superficial myometrial infiltration, placental tissue extruding beyond the uterine serosa, bridging vessel(s), or placental lacunae with high velocity and/or turbulent flow. The primary study outcome was a composite maternal morbidity including cesarean hysterectomy, transfusion of blood or blood products, unintentional cystotomy, or intensive care unit (ICU) admission. Chi-square, Fisher's exact test, and Mann-Whitney U-test were used for analysis. A total of 78 women had a suspected accreta on imaging, 36 with "lower risk" features and 42 with "higher risk" features. There were no differences in baseline maternal demographics. Women in the "higher risk" group were more likely to have a placenta previa (p < 0.01) and preoperative consultation with gynecologic oncology (p = 0.04). There was a significant difference in composite maternal morbidity between patients with "lower risk" and "higher risk" features of accreta on imaging (50 vs. 92.9%, p < 0.01). Median gestational age at planned and actual delivery were earlier in the "higher risk" group (36.6 vs. 34.9 weeks, p < 0.01; 36.0 vs. 34.7 weeks, p < 0.01). Stratification of women with suspected accreta based on imaging corresponded to rates of maternal morbidity and operative complications, and appears to have been used clinically in selecting timing of delivery and interventions. · Increased morbidity with high risk accreta imaging.. · Interventions correlate with accreta imaging risk.. · Imaging can be used to stratify accreta cases..

Immune cell infiltrate at the utero-placental interface is altered in placenta accreta spectrum disorders.

To characterize the immune cell infiltrate associated with maternal vascular remodeling in 12 cases of cesarean hysterectomy from women with placenta accreta spectrum (PAS) disorder. Myometrial vessels were evaluated by hematoxylin and eosin and immunohistochemistry stains on tissue microarrays that included samples from the myometrium, deep to the implantation site. Vessels were quantified based on physiologic conversion and immune cell infiltrates. Placental bed biopsies from cases of repeat cesarean section, and decidual vessels from delivered non-PAS placentas were used as controls. Immune cells, predominantly macrophages and T-cells, were present as a band along the placental-myometrial interface in PAS cases. However, within the myometrium, the infiltrate showed a perivascular accentuation. The infiltrates around and within vessel walls were composed of T-cells (CD3) and macrophages (CD68), with fewer NK (CD56), Treg (FoxP3) and rare B-cells (CD20). Plasma cells (CD138) were absent. The majority of vessels with immune cell infiltrates had undergone complete or partial physiologic conversion by trophoblast. However, a subset of unconverted vessels in the myometrium had a similar immune cell infiltration. Control blood vessels showed a similar pattern of leukocytes infiltration in the decidua and placental bed biopsies, but with a lower density. Our findings suggest that myometrial vascular changes in PAS resemble the physiological changes of vessels noted in the implantation site of normal pregnancies. The presence of perivascular immune cell infiltrates in the absence of adjacent trophoblast suggests that the process may be initiated by paracrine effects rather than direct contact or endovascular growth of trophoblast.

Assessment of the massive hemorrhage in placenta accreta spectrum with magnetic resonance imaging.

The aim of the present study was to evaluate whether MRI features are able to predict massive hemorrhage of patients with placenta accreta spectrum (PAS). A total of 40 patients with suspected PAS after ultrasound examination were subjected to MRI. Of these, 29 patients were confirmed as having PAS. MRI data were analyzed independently by two radiologists in a blinded manner. Inter-observer agreement was determined. The 29 confirmed patients were divided into two groups (moderate and massive hemorrhage) according to the estimated blood loss (EBL) and blood transfusion, and the MRI features were compared between the two groups. The EBL, as well as blood transfusion, between the patients with and without each MRI feature were compared. The inter-observer agreement between the two radiologists for the 11 MRI features had statistical significance (P<0.05). Intra-placental thick dark bands and markedly heterogeneous placenta were the most important MRI features in predicting massive hemorrhage and blood transfusion (P<0.05). The difference in EBL between the patients with and without focal defect of the uteroplacental interface (UPI) was significant (P<0.05). The differences in blood transfusion between the patients with and without myometrial thinning, disruption of the inner layer of the UPI, increased placental vascularity and increased vascularity at the UPI were significant (P<0.05). These results indicate that MRI features may predict massive hemorrhage of patients with PAS, which may be helpful for pre-operative preparation of PAS patients.