Biology subjects

Beristain, A. G.

Publications and source records attributed to Beristain, A. G..

12 recordsLinked to original sources

bioRxiv2025

Low oxygen promotes extravillous trophoblast progenitor expansion but restrains maturation

Placental development occurs in a low oxygen environment, yet how oxygen tension instructs differentiation of progenitor cytotrophoblasts (CTB) along the extravillous versus villous pathways remains incompletely understood. In particular, the role of low oxygen in early extravillous trophoblast (EVT) progenitor expansion and subsequent maturation has been difficult to assess due to the lack of models allowing sequential, high-resolution characterization. Using human trophoblast organoids and single-cell transcriptomics, we examined the effects of ambient (21%) and physiological (2-3%, 8%) oxygen on EVT and SCT differentiation. We show that low oxygen promotes the initial expansion of column CTB-like progenitors but restricts terminal EVT maturation. Conversely, we show that ambient oxygen drives the formation of EVT and syncytiotrophoblast. Stabilization of HIF-1 partially recapitulates the EVT maturation block but does not contribute to EVT progenitor expansion, indicating HIF-dependent and-independent contributions. These findings clarify how oxygen shapes EVT lineage progression and define HIF-1s role in coordinating progenitor expansion versus maturation.

developmental biology↗

bioRxiv2025

Obesogenic diet alters decidual differentiation and cell-cell communication in the mouse uterus

Maternal obesity is associated with increased risk of infertility, implantation failure, miscarriage, and other pregnancy complications. While prior studies have linked obesity to uterine dysfunction and impaired endometrial biology, how obesity alters the cellular and molecular landscape of the early pregnant endometrium remains poorly understood. Here, we perform single-cell RNA sequencing of embryonic day 5.5 uterus from control and obesogenic mice to generate a cellular atlas of the early decidualizing endometrium. We identify obesity-associated transcriptional changes across multiple Endometrial Stromal Cell (ESC) states and innate immune populations, including uterine natural killer cells and macrophages. Computational modeling reveals that maternal obesity disrupts distinct routes of ESC differentiation during decidualization and leads to shifts in ESC-derived cues known to impact innate immune responses. These findings provide a comprehensive single-cell resource of the post-implantation mouse endometrium while simultaneously generating critical insight into how maternal obesity reprograms the maternal-fetal interface in early pregnancy.

developmental biology↗

bioRxiv2025

A blastocyst-derived in vitro model of the human chorion

The placenta supports the foetus by mediating nutrient and gas exchange, hormone production, and immune protection. Yet, human placental biology remains poorly understood due to limited in vitro models. The foetal part of the placenta, the chorion, consists of a trophoblast-derived layer and a mesenchymal zone containing extraembryonic mesoderm cells. Here, we show that human blastocysts can give rise to both trophoblast organoids and extraembryonic mesoderm cells under the same culture conditions. Trophoblast organoids originate from both outer trophoblast cells and inner cells of the blastocyst, while extraembryonic mesoderm cells derive exclusively from inner cells. These organoids recapitulate the cellular composition, morphology, and function of the in vivo trophoblast. Moreover, given the high rate of aneuploidy at the blastocyst stage, aneuploid trophoblast organoids can be readily generated. These models reflect the trophoblasts unique ability to tolerate aneuploidy and offer a valuable platform to study human placental development and pathophysiology.

developmental biology↗

bioRxiv2024

RNA sequencing reveals the developmental onset of autosomal gene expression differences in male and female extravillous trophoblasts

BackgroundThe human placenta is an essential organ for fetal development and pregnancy success. Across gestation, blastocyst-derived trophoblasts facilitate the major functions of the placenta. Specifically, invasive trophoblast subtypes, called extravillous trophoblasts (EVT), play central roles in coordinating nutrient accessibility and maternal immunomodulation to semi-allogeneic fetal and placental tissues. Like the fetus, these trophoblasts can be chromosomally male (XY) or female (XX). While male and female trophoblasts are associated with distinct placental gene signatures, specific differences between male and female EVT have not been defined across the first trimester. MethodsTo understand how male and female EVT differ, we subjected male and female first trimester EVT cell preparations to bulk RNA sequencing. Concurrently, publicly available single-cell RNA sequencing datasets of first trimester placental and decidual tissues were utilized to resolve EVT differentiation and EVT subtype-specific sex differences. Candidate genes were then selected and immuno-localized to specific regions and cell populations in male and female placentas. ResultsWe found that before week 10 of gestation, both male and female EVT lineage cells increase expression of transcripts associated with cell proliferation. Sex-related gene differences within this early developmental time-point are restricted to genes residing on sex chromosomes. Following week 10 of gestation, there is a broad up-regulation of genes linked to immunoregulation in male and female EVT. However, within this later developmental period, autosomal gene differences appear in relation to biological sex. We go on to show that these sex-dependent autosomal gene differences influence EVT-maternal cell signalling within the uterus whereby pregnancies exposed to a male placenta demonstrate more complex MIF and CD99 as well as angiogenesis-associated VEGF cell-cell signals between male EVT and the female maternal immune and non-immune cells found throughout the uterus. ConclusionsThese findings resolve early first trimester EVT lineage trophoblast sex differences and highlight a developmental timepoint that is critical to male and female autosomal gene expression. HIGHLIGHTSO_LIFirst trimester male and female placenta cells were compared using bulk and single-cell transcriptomics C_LIO_LIGestational age and placental sex are the leading drivers of variation in gene expression C_LIO_LISex-related differences in autosomal genes generally arise on week 10 of gestation C_LIO_LISex-related differences in trophoblast and uterine cell crosstalk are driven by autosomal gene differences arising after week 10 of gestation C_LI PLAIN ENGLISH SUMMARYThe human placenta is a temporary organ that forms during pregnancy. Importantly, the placenta acts as a surrogate for not yet functioning fetal organ systems (i.e., the heart, lungs, and kidneys) while they mature within the fetus. Because the placenta develops from cells of the early embryo, it can be biologically male or female. Male and female placentas are genetically different from each other, where these differences may differentially influence placental functions and pregnancy health through unknown mechanisms. Therefore, this study aimed to understand how male and female placenta cells differ at the level of gene expression. We find that on week 10 of gestation, but not before, female placenta cells express a different repertoire of genes compared to male placenta cells. We show that these differences potentially affect how cells of the placenta and uterus interact with each other. Taken together, these results identify a developmental timepoint in pregnancy where the biological sex of the placenta may instruct subtle differences in how male or female placenta cells communicate with the maternal compartment in pregnancy. Summary StatementBulk and single-cell RNA sequencing provides comprehensive comparison between uncultured male and female HLA-G-purified trophoblasts derived from first-trimester human placentas.

developmental biology↗

bioRxiv2024

Maternal obesogenic diet disrupts mid-gestation decidual immune and vascular homeostasis without impairing spiral artery remodelling

Excess maternal adiposity (i.e., overweight and obesity) during pregnancy has been linked to impaired uteroplacental perfusion, compromised placental development, and a higher risk of adverse pregnancy outcomes. Owing to the nature of chronic inflammation and immune dysregulation accompanying excess adiposity, disruption of leukocyte-mediated tissue remodelling and immunoregulation within the decidua have emerged as likely drivers contributing to suboptimal placental function in pregnancies impacted by maternal overweight or obesity. However, the impacts of excess adiposity on major populations of innate lymphoid cells (ILCs) and macrophages which orchestrate these processes and the environment that these cells occupy remain vastly understudied. Here, we used a mouse model of chronic high-fat, high-sucrose (HFHS) diet-feeding to characterize the impacts of an obesogenic milieu on decidual immune dynamics during placental development at mid-gestation (E10.5). HFHS pregnancies exhibited marked increases in total decidual leukocyte abundance, driven by population-level increases in tissue-resident and conventional NK cells, and MHC-II+ macrophages. This was not associated with abnormalities in implantation site morphology or decidual spiral artery remodelling but was coincident with histological patterns of local inflammation. In line with this, expression of canonical proinflammatory cytokines and chemokines were moderately upregulated in bulk decidual tissue of HFHS dams. This was accompanied by more potent elevations in multiple mediators of angiogenesis, endothelial activation, and coagulation in HFHS decidual tissue. Collectively, these findings point towards pathological vascular inflammation and possibly dysregulated decidual angiogenesis in the first half of pregnancy as factors predisposing to reduced placental efficiency, malperfusion, and inflammation seen in pregnancies affected by maternal overweight and obesity.

developmental biology↗

bioRxiv2022

Single-cell assessment of trophoblast stem cell-based organoids as human placenta-modeling platforms

The recent discovery of human trophoblast stem cells (hTSC) and techniques allowing for trophoblast organoid (TOrg) culture have established promising approaches for studying human trophoblast development. To validate the accuracy of these models at single-cell resolution, we directly compared in vitro TOrg cultures derived from primary progenitor cytotrophoblasts (CTB) or commercially available hTSC lines to in vivo human trophoblasts using a scRNA-seq approach. While patient-derived (PD)- and hTSC-derived TOrgs overall reflect cell differentiation trajectories with accuracy, specific features related to trophoblast state make-up, distinct sub-paths of differentiation, and predicted transcriptional drivers regulating stem cell maintenance were shown to be misaligned in the in vitro platforms. This is best exemplified by the identification of a distinct progenitor state in hTSC-derived TOrgs that showed characteristics of CTB- and extravillous-like cell states. Together, this work provides a comprehensive resource that identifies underlying strengths and limitations of current TOrg platforms. Summary StatementSingle-cell transcriptomics provides comprehensive comparison between trophoblast organoids derived from commercially available trophoblast stem cells and first-trimester primary human cytotrophoblasts. HIGHLIGHTSO_LIAn integrated single cell transcriptomic atlas of placental and organoid trophoblasts establishes a comprehensive and public web-based resource C_LIO_LIDirect comparison of trophoblasts from placental/decidual tissue to trophoblasts extracted from two distinct organoid platforms highlights both conserved and divergent features C_LIO_LIComputational modeling describes novel trophoblast states and routes of cell differentiation in human trophoblast organoids C_LI IN BRIEFWhile the merits and utility of current trophoblast organoid cultures have been established, high-resolution assessment and comparison of conserved and divergent features of these systems to cell states and differentiation trajectories of trophoblasts in situ or in vitro has not been performed. Here, Shannon et al. generate a single-cell transcriptomic atlas of two trophoblast organoids that comprehensively define the similarities and discrepancies in relation to trophoblasts from the placental-maternal interface.

developmental biology↗

bioRxiv2022

Transcriptomic mapping of the metzincin landscape in human trophoblasts

The metzincin family of metalloproteases coordinates cell and tissue developmental processes through regulation of growth factor availability, receptor signaling, and cell-cell/cell-matrix adhesion. During placental development, while distinct roles for metzincin proteases in controlling specific trophoblast functions have been described, a comprehensive assessment of metzincins during discrete stages of trophoblast differentiation has yet to be performed. Here we provide a comprehensive single cell transcriptomic resource of metzincin protease expression in diverse states of human trophoblasts from first trimester placental and decidual tissues. In the 8 distinct trophoblasts states categorized [four progenitor cytotrophoblast (CTB), one syncytiotrophoblast precursor (SCTp), two column CTB (cCTB), and one extravillous trophoblast (EVT) state], we identified 24 metzincin genes. These included 12 adamalysins, 2 pappalysins, 3 astacins and 7 matrixins. Cell trajectory modeling shows that expression of most (19/24) metzincins increases across CTB to EVT differentiation, though select proteases also increase as CTB fuse into syncytiotrophoblast. Within the CTB niche, single-cell velocity ordering identified 11 metzincins (ADAM10, -17, MMP14, -15, -19, -23B, ADAMTS1, -6, -19, TLL-1, -2) expressed in progenitors proximal to the predicted origin. Analysis of metzincin-substrate interactions within the CTB niche revealed [~]150 substrates and binding partners, including FBN2 as an ADAMTS6-specific substrate preferentially expressed in trophoblast progenitors. Together, this work characterizes the metzincin transcriptomic landscape in human first trimester trophoblasts and establishes insight into the roles specific proteases perform within distinct trophoblast niches and across differentiation. This resource serves as a guide for future investigations into the roles of metzincin proteases in human placental development. Summary StatementSingle cell RNA sequencing characterizes the expression of multiple metzincin proteases within first trimester placental trophoblasts. Examination of protease-substrate interactions within cytotrophoblasts identifies potential interactions between ADAMTS6 and FBN2. HighlightsO_LISingle cell RNA sequencing identifies 24 distinct metzincin proteases expressed in human first trimester trophoblasts C_LIO_LILineage trajectory modelling shows that metzincin genes are dynamic and likely control processes in progenitor, mid-point, and end-point states of trophoblast differentiation. C_LIO_LIADAMTS6, and its putative substrate FBN2, localize specifically to progenitor trophoblasts C_LI

developmental biology↗

bioRxiv2022

Decidual innate immune cell kinetics following lipopolysaccharide challenge

In early pregnancy, macrophages (M{varphi}) and natural killer cells (NK) infiltrate and expand within the decidua to comprise 30% of all cellular content. These immune cell populations coordinate angiogenic and tissue remodeling processes that are needed for a healthy pregnancy. Importantly, decidual tissue-resident macrophages (trM{varphi}) and uterine NK retain immunosurveillance properties that facilitate the targeting of infections (e.g., viral, bacterial). The timing and severity of these infections, as well as the resulting immune response, can dictate pregnancy outcome. However, little is known about the kinetics and activities of uterine myeloid and NK populations following infections. To address this knowledge gap, we defined the stepwise changes of uterine myeloid and NK subpopulations following lipopolysaccharide (LPS) challenge in a mouse model of early pregnancy. Low (25 {micro}g/kg), moderate (50 {micro}g/kg), and high (200 {micro}g/kg) doses of LPS resulted in dose-dependent increases in peripheral and uterine inflammation, as well as a dose-dependent increase in the rate of fetal resorption. Compared with saline controls, mice exposed to LPS showed higher frequencies of immature monocytes, decreased TNF-producing monocytes and M{varphi}, and increased conventional (c)NK expression of granzyme B in the uterus. These changes were followed by alterations in overall uterine (u)NK frequencies with increased cNK and decreased tissue resident (tr)NK. Together, this work describes how discrete levels of LPS-induced inflammation shape the innate immune cell landscape of the decidua. These findings establish insight into the stepwise immunological changes following endotoxin challenge and provide a better understanding of how inflammation controls the activity of key decidual leukocytes. Summary sentenceGraded LPS challenge in early pregnancy leads to a stepwise increase in fetal resorption and associates with distinct alterations in frequencies and activities of uterine immune cells.

immunology↗

bioRxiv2021

Single cell trajectory modeling identifies a primitive trophoblast state defined by BCAM enrichment

In early placental development, progenitor cytotrophoblasts (CTBs) differentiate along one of two cellular trajectories: the villous or extravillous pathways. CTBs committed to the villous pathway fuse with neighboring CTBs to form the outer multinucleated syncytiotrophoblast (SCT), while CTBs committed to the extravillous pathway differentiate into invasive extravillous trophoblasts (EVT). Unfortunately, little is known about the processes controlling human CTB progenitor maintenance and differentiation. To address this, we established a single cell RNA sequencing (scRNA-seq) dataset from first trimester placentas to identify cell states important in trophoblast progenitor establishment, renewal, and differentiation. Multiple distinct trophoblast states were identified, representing progenitor CTBs, column CTBs, SCT precursors, and EVT. Lineage trajectory analysis identified a progenitor origin that was reproduced in human trophoblast stem cell organoids. Heightened expression of basal cell adhesion molecule (BCAM) defined this primitive state, where BCAM enrichment or gene silencing resulted in enhanced or diminished organoid growth. Together, this work describes at high-resolution trophoblast heterogeneity within the first trimester, resolves gene networks within human CTB progenitors, and identifies BCAM as a primitive progenitor marker and possible regulator. Summary StatementLineage trajectory modeling identifies multiple human progenitor trophoblast states and defines trophoblast differentiation kinetics, where BCAM-expressing progenitors demonstrate enhanced regenerative ability.

developmental biology↗

bioRxiv2019

Low oxygen enhances trophoblast column growth by potentiating the extravillous lineage and promoting LOX activity

Early placental development and the establishment of the invasive trophoblast lineage take place within a low oxygen environment. However, conflicting and inconsistent findings have obscured the role of oxygen in regulating invasive trophoblast differentiation. In this study, the effect of hypoxic, normoxic, and atmospheric oxygen on invasive extravillous pathway progression was examined using a human placental explant model. Here, we show that exposure to low oxygen enhances extravillous column outgrowth and promotes the expression of genes that align with extravillous trophoblast (EVT) lineage commitment. By contrast, super-physiological atmospheric levels of oxygen promote trophoblast proliferation while simultaneously stalling EVT progression. Low oxygen-induced EVT differentiation coincided with elevated transcriptomic levels of lysyl oxidase (LOX) in trophoblast anchoring columns, where functional experiments established a role for LOX activity in promoting EVT column outgrowth. The findings of this work support a role for low oxygen in potentiating the differentiation of trophoblasts along the extravillous pathway. Additionally, these findings generate insight into new molecular processes controlled by oxygen during early placental development.\n\nSummary StatementLow oxygen promotes extravillous trophoblast differentiation

developmental biology↗

bioRxiv2018

A mouse model of maternal obesity leads to uterine natural killer (uNK) cell activation and uterine artery remodeling defects

Maternal obesity associates with multiple adverse reproductive outcomes, negatively affecting the health and survival of both the mother and the fetus. The contributory effects of obesity on adipose-derived immune changes have been well established, however the mechanisms that link obesity to pregnancy complications remain unclear. Proper development of the placenta and establishment of utero-placental vasculature is essential in early pregnancy to allow for optimal fetal growth and survival. Uterine immune cells, particularly uterine natural killer (uNK) cells, play fundamental roles in promoting these events. Using an obesogenic high-fat/high-sucrose (HFD) mouse model of maternal obesity, uNK cells and placenta/uterine vascular remodeling were examined at gestational days (Gd) 10.5 and 14.5 of pregnancy. While mice fed a HFD 13 weeks prior to pregnancy significantly gained more weight than control mice fed a low-fat/no-sucrose diet (LFD), fetal survival was not different in either diet. At Gd 10.5, HFD had no effect on total uNK proportions, nor did it affect proportions of distinct CD122+/CD49a tissue resident or CD122+/DX5+ conventional uNKs. However, HFD resulted in increased proportions of NCR1+ uNK and overall heightened uNK activity. Moreover, HFD resulted in impairments in uterine vascular remodeling at Gd10.5. By Gd14.5, uterine artery defects were no longer observed and placental structure was comparable between HFD and LFD mice. Gene analysis of IFN{gamma}, TNF and VEGFA in Gd10.5 uNK indicated that, while not significant, a HFD leads to subtle alterations in uNK cytokine gene expression. These findings show that HFD in mice results in changes in uNK biology and temporary uterine artery remodeling impairments. Further, this work establishes insight into the cellular changes occurring in early pregnancy as a result of HFD exposure.

immunology↗

bioRxiv2017

Maternal obesity alters uterine NK cell activity through a functional KIR2DL1/S1 imbalance

In pregnancy, uterine natural killer cells (uNK) play essential roles in coordinating uterine angiogenesis, blood vessel remodeling, and promoting maternal tolerance to fetal tissue. Deviances from a normal uterine microenvironment are thought to modify uNK function(s), limiting their ability to establish a healthy pregnancy. While maternal obesity has become a major health concern due to associations with adverse effects on fetal and maternal health, our understanding into how obesity contributes to poor pregnancy disorders is essentially unknown. Given the importance of uNK in pregnancy, this study sets out to examine if obesity affects uNK function. Using a cohort of pregnant women, we show that baseline activity of uNK from obese women is elevated, but that enhanced activity does not equate to increased killing potential. Instead, obesity associates with altered uNK production of angiogenic VEGF-A and PlGF. These changes coincide with alterations in NKp46+ and NKG2A+ uNK subsets and elevated expression of KIR2D(L1/S1/S3/S5) receptors. Detailed examination revealed that obesity leads to imbalances in KIR2DL1/S1 expression that together instruct altered responses to HLA-C2 antigen, including increased production of TNF. Together, these findings suggest that maternal obesity modulates uNK function by altering angiokine/cytokine production and the response to HLA-C2 antigen.

immunology↗