Pregnancy-specific 1-glycoprotein Research Articles

Pregnancy-Specific Glycoprotein 1 (PSG1) Interactome Networks in Health and Disease

Pregnancy-Specific Glycoprotein 1 (PSG1) Interactome Networks in Health and Disease

The immuno-regulatory activity of placentally secreted pregnancy-specific glycoprotein (PSG) 1

The immuno-regulatory activity of placentally secreted pregnancy-specific glycoprotein (PSG) 1

Two waves of evolution in the rodent pregnancy-specific glycoprotein (Psg) gene family lead to structurally diverse PSGs

BackgroundThe evolution of pregnancy-specific glycoprotein (PSG) genes within the CEA gene family of primates correlates with the evolution of hemochorial placentation about 45 Myr ago. Thus, we hypothesized that hemochorial placentation with intimate contact between fetal cells and maternal immune cells favors the evolution and expansion of PSGs. With only a few exceptions, all rodents have hemochorial placentas thus the question arises whether Psgs evolved in all rodent genera.ResultsIn the analysis of 94 rodent species from 4 suborders, we identified Psg genes only in the suborder Myomorpha in three families (characteristic species in brackets), namely Muridae (mouse), Cricetidae (hamster) and Nesomyidae (giant pouched rat). All Psgs are located, as previously described for mouse and rat, in a region of the genome separated from the Cea gene family locus by several megabases, further referred to as the rodent Psg locus. In the suborders Castorimorpha (beaver), Hystricognatha (guinea pig) and Sciuromorpha (squirrel), neither Psg genes nor so called CEA-related cell adhesion molecule (Ceacam) genes were found in the Psg locus. There was even no evidence for the existence of Psgs in any other genomic region. In contrast to the Psg-harboring rodent species, which do not have activating CEACAMs, we were able to identify Ceacam genes encoding activating CEACAMs in all other rodents studied. In the Psg locus, there are genes encoding three structurally distinct CEACAM/PSGs: (i) CEACAMs composed of one N- and one A2-type domain (CEACAM9, CEACAM15), (ii) composed of two N domains (CEACAM11-CEACAM14) and (iii) composed of three to eight N domains and one A2 domain (PSGs). All of them were found to be secreted glycoproteins preferentially expressed by trophoblast cells, thus they should be considered as PSGs.ConclusionIn rodents Psg genes evolved only recently in the suborder Myomorpha shortly upon their most recent common ancestor (MRCA) has coopted the retroviral genes syncytin-A and syncytin-B which enabled the evolution of the three-layered trophoblast. The expansion of Psgs is limited to the Psg locus most likely after a translocation of a CEA-related gene – possibly encoding an ITAM harboring CEACAM. According to the expression pattern two waves of gene amplification occurred, coding for structurally different PSGs.

Effect of pregnancy-specific β1-glycoprotein on the expression of arginase-1 and indolamine-2,3-dioxygenase by myeloid-derived suppressor cells

Myeloid-derived suppressor cells (MDSC) - a population of immature cells of myeloid origin with inhibitory functions, mainly related to T lymphocytes. Normally, MDSC account for less than 1% of leukocytes in peripheral blood. The number of these cells increases during healthy pregnancy. However, MDSC have been shown to play a critical role in the maintenance of tumor growth and in autoimmune diseases.
 Because MDSC are now considered important regulators of immunity, finding ways to manipulate their functions is important for the development of therapies for malignant and autoimmune diseases, as well as for pregnancy pathologies and post-transplant complications. The immunosuppressive mechanisms of these cells are mediated by their expression of the surface molecules CD73, ADAM17, PD -L1, the enzymes arginase 1 (Arg 1), inducible nitric oxide synthase (iNOS), and indoleamine 2,3-dioxygenase (IDO), reactive oxygen species, and the production of the anti-inflammatory cytokines IL -10 and TGF-1.
 Pregnancy-specific 1-glycoprotein (PSG) is a pregnancy glycoprotein that has immunomodulatory effects on natural (dendritic cells and macrophages) and adaptive (T cells) immunity cells. At the same time, the effect of PSG on MDSC has not been investigated so far. Since this glycoprotein has promising pharmacological applications, it is necessary to study not only the native variant of PSG but also its recombinant form.
 Since the main function of MDSC is immunosuppression, the aim of our work was to evaluate one of its mechanisms, namely the intracellular expression of amino acid degradation enzymes Arg1 and IDO under the influence of native and recombinant PSG in vitro.
 MDSC differentiation was performed from CD11b+ cells isolated from peripheral blood of healthy volunteers. Cells were cultured for 7 days with stepwise addition of GM-CSF, IL -1, and LPS. Native (n) (1, 10, and 100 g/mL) and recombinant (r) (1 and 10 g/mL) PSG was added to the cultures three days before the end of incubation. The percentage of MDSCs (Lin- HLA-DR -CD11b+CD33+) intracellularly expressing Arg1 and IDO was determined by flow cytometry.
 It was found that nPSG and rPSG did not alter the amount of Arg1-expressing MDSCs at all concentrations examined. However, at a concentration of 10 g/mL, both types of proteins caused a statistically significant increase in the percentage of cells expressing IDO.
 We have already established that nPSG and rPSG affect MDSC differentiation by increasing the proportion of these cells belonging to the monocytic subpopulation. However, now we can say that PSG, in addition, enhances the suppressive function of the studied cells.
 The obtained data are novel and open perspectives for targeting myeloid suppressor cells to improve cellular technologies in science and medicine.

A unique maternal and placental galectin signature upon SARS-CoV-2 infection suggests galectin-1 as a key alarmin at the maternal-fetal interface.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic imposed a risk of infection and disease in pregnant women and neonates. Successful pregnancy requires a fine-tuned regulation of the maternal immune system to accommodate the growing fetus and to protect the mother from infection. Galectins, a family of β-galactoside-binding proteins, modulate immune and inflammatory processes and have been recognized as critical factors in reproductive orchestration, including maternal immune adaptation in pregnancy. Pregnancy-specific glycoprotein 1 (PSG1) is a recently identified gal-1 ligand at the maternal-fetal interface, which may facilitate a successful pregnancy. Several studies suggest that galectins are involved in the immune response in SARS-CoV-2-infected patients. However, the galectins and PSG1 signature upon SARS-CoV-2 infection and vaccination during pregnancy remain unclear. In the present study, we examined the maternal circulating levels of galectins (gal-1, gal-3, gal-7, and gal-9) and PSG1 in pregnant women infected with SARS-CoV-2 before vaccination or uninfected women who were vaccinated against SARS-CoV-2 and correlated their expression with different pregnancy parameters. SARS-CoV-2 infection or vaccination during pregnancy provoked an increase in maternal gal-1 circulating levels. On the other hand, levels of PSG1 were only augmented upon SARS-CoV-2 infection. A healthy pregnancy is associated with a positive correlation between gal-1 concentrations and gal-3 or gal-9; however, no correlation was observed between these lectins during SARS-CoV-2 infection. Transcriptome analysis of the placenta showed that gal-1, gal-3, and several PSG and glycoenzymes responsible for the synthesis of gal-1-binding glycotopes (such as linkage-specific N-acetyl-glucosaminyltransferases (MGATs)) are upregulated in pregnant women infected with SARS-CoV-2. Collectively, our findings identify a dynamically regulated "galectin-specific signature" that accompanies the SARS-CoV-2 infection and vaccination in pregnancy, and they highlight a potentially significant role for gal-1 as a key pregnancy protective alarmin during virus infection.

Single-cell analysis reveals transcriptomic and epigenomic impacts on the maternal–fetal interface following SARS-CoV-2 infection

During pregnancy the maternal–fetal interface plays vital roles in fetal development. Its disruption is frequently found in pregnancy complications. Recent studies show increased incidences of adverse pregnancy outcomes in patients with COVID-19; however, the mechanism remains unclear. Here we analysed the molecular impacts of SARS-CoV-2 infection on the maternal–fetal interface. Generating bulk and single-nucleus transcriptomic and epigenomic profiles from patients with COVID-19 and control samples, we discovered aberrant immune activation and angiogenesis patterns in distinct cells from patients. Surprisingly, retrotransposons were also dysregulated in specific cell types. Notably, reduced enhancer activities of LTR8B elements were functionally linked to the downregulation of pregnancy-specific glycoprotein genes in syncytiotrophoblasts. Our findings revealed that SARS-CoV-2 infection induced substantial changes to the epigenome and transcriptome at the maternal–fetal interface, which may be associated with pregnancy complications.

Pregnancy-Specific Glycoprotein 9 Enhances Store-Operated Calcium Entry and Nitric Oxide Release in Human Umbilical Vein Endothelial Cells

We explored changes in pregnancy-specific glycoprotein 9 (PSG9) levels in the serum of patients with preeclampsia and the effects and underlying mechanisms of PSG9 effects on calcium (Ca2+) homeostasis and nitric oxide (NO) release in human umbilical vein endothelial cells (HUVECs). Western blotting was used to detect protein expression levels, and an NO fluorescence probe was used to examine NO production. Intracellular Ca2+ concentrations were measured using a Ca2+-sensitive fluorescent dye under a fluorescence microscope. Compared with those in healthy pregnant women, serum PSG9 levels were significantly decreased in patients with preeclampsia. PSG9 (0.1 μg/mL) treatment of HUVECs significantly enhanced the expression levels of store-operated calcium entry (SOCE) channel proteins Orai1 and Orai2, but not Orai3, and of endothelial nitric oxide synthase (eNOS) and NO production. Pretreatment with an inhibitor of SOCE (BTP2) abolished PSG9-enhanced Orai1, Orai2, and eNOS expression levels and NO production in HUVECs. The mechanisms underlying SOCE that were PSG9 enhanced in HUVECs appear to involve the Ca2+/eNOS/NO signaling pathway. These findings suggest that serum PSG9 levels may be a potential biomarker for monitoring the occurrence or development of preeclampsia in pregnancy and that PSG9 may be a potential therapeutic target for the treatment of preeclampsia.

Characterization of placental endocrine function and fetal brain development in a mouse model of small for gestational age.

Conditions such as small for gestational age (SGA), which is defined as birthweight less than 10th percentile for gestational age can predispose to neurodevelopmental abnormalities compared to babies with normal birthweight. Fetal growth and birthweight depend on placental function, as this organ transports substrates to the developing fetus and it acts as a source of endocrine factors, including steroids and prolactins that are required for fetal development and pregnancy maintenance. To advance our knowledge on the aetiology of fetal growth disorders, the vast majority of the research has been focused on studying the transport function of the placenta, leaving practically unexplored the contribution of placental hormones in the regulation of fetal growth. Here, using mice and natural variability in fetal growth within the litter, we compared fetuses that fell on or below the 10th percentile (classified as SGA) with those that had adequate weight for their gestational age (AGA). In particular, we compared placental endocrine metabolism and hormone production, as well as fetal brain weight and expression of developmental, growth and metabolic genes between SGA and AGA fetuses. We found that compared to AGA fetuses, SGA fetuses had lower placental efficiency and reduced capacity for placental production of hormones (e.g. steroidogenic gene Cyp17a1, prolactin Prl3a1, and pregnancy-specific glycoproteins Psg21). Brain weight was reduced in SGA fetuses, although this was proportional to the reduction in overall fetal size. The expression of glucose transporter 3 (Slc2a3) was reduced despite the abundance of AKT, FOXO and ERK proteins were similar. Developmental (Sv2b and Gabrg1) and microglia genes (Ier3), as well as the pregnancy-specific glycoprotein receptor (Cd9) were lower in the brain of SGA versus AGA fetuses. In this mouse model of SGA, our results therefore demonstrate that placental endocrine dysfunction is associated with changes in fetal growth and fetal brain development.

CEACAMS 1, 5, and 6 in disease and cancer: interactions with pathogens.

The CEA family comprises 18 genes and 11 pseudogenes located at chromosome 19q13.2 and is divided into two main groups: cell surface anchored CEA-related cell adhesion molecules (CEACAMs) and the secreted pregnancy-specific glycoproteins (PSGs). CEACAMs are highly glycosylated cell surface anchored, intracellular, and intercellular signaling molecules with diverse functions, from cell differentiation and transformation to modulating immune responses associated with infection, inflammation, and cancer. In this review, we explore current knowledge surrounding CEACAM1, CEACAM5, and CEACAM6, highlight their pathological significance in the areas of cancer biology, immunology, and inflammatory disease, and describe the utility of murine models in exploring questions related to these proteins.

Perturbation of placental protein glycosylation by endoplasmic reticulum stress promotes maladaptation of maternal hepatic glucose metabolism

Placental hormones orchestrate maternal metabolic adaptations to support pregnancy. We hypothesized that placental ER stress, which characterizes early-onset pre-eclampsia (ePE), compromises glycosylation, reducing hormone bioactivity and these maladaptations predispose the mother to metabolic disease in later life. We demonstrate ER stress reduces the complexity and sialylation of trophoblast protein N-glycosylation, while aberrant glycosylation of vascular endothelial growth factor reduced its bioactivity. ER stress alters the expression of 66 of the 146 genes annotated with "protein glycosylation" and reduces the expression of sialyltransferases. Using mouse placental explants, we show ER stress promotes the secretion of mis-glycosylated glycoproteins. Pregnant mice carrying placentas with junctional zone-specific ER stress have reduced blood glucose, anomalous hepatic glucose metabolism, increased cellular stress and elevated DNA methyltransferase 3A. Using pregnancy-specific glycoproteins as a readout, we also demonstrate aberrant glycosylation of placental proteins in women with ePE, thus providing a mechanistic link between ePE and subsequent maternal metabolic disorders.

Proteomic Analysis of Effects of Spironolactone in Heart Failure With Preserved Ejection Fraction.

The TOPCAT trial (Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist Trial) suggested clinical benefits of spironolactone treatment among patients with heart failure with preserved ejection fraction enrolled in the Americas. However, a comprehensive assessment of biologic pathways impacted by spironolactone therapy in heart failure with preserved ejection fraction has not been performed. We conducted aptamer-based proteomic analysis utilizing 5284 modified aptamers to 4928 unique proteins on plasma samples from TOPCAT participants from the Americas (n=164 subjects with paired samples at baseline and 1 year) to identify proteins and pathways impacted by spironolactone therapy in heart failure with preserved ejection fraction. Mean percentage change from baseline was calculated for each protein. Additionally, we conducted pathway analysis of proteins altered by spironolactone. Spironolactone therapy was associated with proteome-wide significant changes in 7 proteins. Among these, CARD18 (caspase recruitment domain-containing protein 18), PKD2 (polycystin 2), and PSG2 (pregnancy-specific glycoprotein 2) were upregulated, whereas HGF (hepatic growth factor), PLTP (phospholipid transfer protein), IGF2R (insulin growth factor 2 receptor), and SWP70 (switch-associated protein 70) were downregulated. CARD18, a caspase-1 inhibitor, was the most upregulated protein by spironolactone (-0.5% with placebo versus +66.5% with spironolactone, P<0.0001). The top canonical pathways that were significantly associated with spironolactone were apelin signaling, stellate cell activation, glycoprotein 6 signaling, atherosclerosis signaling, liver X receptor activation, and farnesoid X receptor activation. Among the top pathways, collagens were a consistent theme that increased in patients receiving placebo but decreased in patients randomized to spironolactone. Proteomic analysis in the TOPCAT trial revealed proteins and pathways altered by spironolactone, including the caspase inhibitor CARD18 and multiple pathways that involved collagens. In addition to effects on fibrosis, our studies suggest potential antiapoptotic effects of spironolactone in heart failure with preserved ejection fraction, a hypothesis that merits further exploration.

Recombinant pregnancy-specific glycoprotein-1-Fc reduces functional deficit in a mouse model of permanent brain ischaemia

BackgroundThe well-characterised role of the immune system in acute ischaemic stroke has prompted the search for immunomodulatory therapies. Pregnancy-specific glycoproteins (PSGs) are a group of proteins synthesised by placental trophoblasts which show immunomodulatory properties. The aim of this study was to determine whether a proposed PSG1-based therapeutic enhanced recovery in a mouse model of brain ischaemia and to explore possible immunomodulatory effects. MethodsMice underwent permanent electrocoagulation of the left middle cerebral artery (pMCAO). They received saline (n = 20) or recombinant pregnancy-specific glycoprotein-1-alpha “fused” to the Fc domain of IgG1 (rPSG1-Fc) (100 μg) (n = 22) at 1 h post-ischaemia. At 3 and 5 days post-ischaemia, neurobehavioural recovery was assessed by the grid-walking test. At 5 days post-ischaemia, lesion size was determined by NeuN staining. Peripheral T cell populations were quantified via flow cytometry. Immunohistochemistry was used to quantify ICAM-1 expression and FoxP3+ cell infiltration in the ischaemic brain. Immunofluorescence was employed to determine microglial activation status via Iba-1 staining.Results: rPSG1-Fc significantly enhanced performance in the grid-walking test at 3 and 5 days post-ischaemia. No effect on infarct size was observed. A significant increase in circulating CD4+ FoxP3+ cells and brain-infiltrating FoxP3+ cells was noted in rPSG1-Fc-treated mice. Among CD4+ cells, rPSG1-Fc enhanced the expression of IL-10 in spleen, blood, draining lymph nodes, and non-draining lymph nodes, while downregulating IFN-γ and IL-17 in spleen and blood. A similar cytokine expression pattern was observed in CD8+ cells. rPSG1-Fc reduced activated microglia in the infarct core. ConclusionThe administration of rPSG1-Fc improved functional recovery in post-ischaemic mice without impacting infarct size. Improved outcome was associated with a modulation of the cytokine-secreting phenotype of CD4+ and CD8+ T cells towards a more regulatory phenotype, as well as reduced activation of microglia. This establishes proof-of-concept of rPSG1-Fc as a potential stroke immunotherapy.

A locus at 19q13.31 significantly reduces the ApoE ε4 risk for Alzheimer's Disease in African Ancestry.

African descent populations have a lower Alzheimer disease risk from ApoE ε4 compared to other populations. Ancestry analysis showed that the difference in risk between African and European populations lies in the ancestral genomic background surrounding the ApoE locus (local ancestry). Identifying the mechanism(s) of this protection could lead to greater insight into the etiology of Alzheimer disease and more personalized therapeutic intervention. Our objective is to follow up the local ancestry finding and identify the genetic variants that drive this risk difference and result in a lower risk for developing Alzheimer disease in African ancestry populations. We performed association analyses using a logistic regression model with the ApoE ε4 allele as an interaction term and adjusted for genome-wide ancestry, age, and sex. Discovery analysis included imputed SNP data of 1,850 Alzheimer disease and 4,331 cognitively intact African American individuals. We performed replication analyses on 63 whole genome sequenced Alzheimer disease and 648 cognitively intact Ibadan individuals. Additionally, we reproduced results using whole-genome sequencing of 273 Alzheimer disease and 275 cognitively intact admixed Puerto Rican individuals. A further comparison was done with SNP imputation from an additional 8,463 Alzheimer disease and 11,365 cognitively intact non-Hispanic White individuals. We identified a significant interaction between the ApoE ε4 allele and the SNP rs10423769_A allele, (β = -0.54,SE = 0.12,p-value = 7.50x10-6) in the discovery data set, and replicated this finding in Ibadan (β = -1.32,SE = 0.52,p-value = 1.15x10-2) and Puerto Rican (β = -1.27,SE = 0.64,p-value = 4.91x10-2) individuals. The non-Hispanic Whites analyses showed an interaction trending in the “protective” direction but failing to pass a 0.05 significance threshold (β = -1.51,SE = 0.84,p-value = 7.26x10-2). The presence of the rs10423769_A allele reduces the odds ratio for Alzheimer disease risk from 7.2 for ApoE ε4/ε4 carriers lacking the A allele to 2.1 for ApoE ε4/ε4 carriers with at least one A allele. This locus is located approximately 2 mB upstream of the ApoE locus, in a large cluster of pregnancy specific beta-1 glycoproteins on chromosome 19 and lies within a long noncoding RNA, ENSG00000282943.This study identified a new African-ancestry specific locus that reduces the risk effect of ApoE ε4 for developing Alzheimer disease. The mechanism of the interaction with ApoEε4 is not known but suggests a novel mechanism for reducing the risk for ε4 carriers opening the possibility for potential ancestry-specific therapeutic intervention.

Evolution of Placental Hormones: Implications for Animal Models.

Human placenta secretes a variety of hormones, some of them in large amounts. Their effects on maternal physiology, including the immune system, are poorly understood. Not one of the protein hormones specific to human placenta occurs outside primates. Instead, laboratory and domesticated species have their own sets of placental hormones. There are nonetheless several examples of convergent evolution. Thus, horse and human have chorionic gonadotrophins with similar functions whilst pregnancy-specific glycoproteins have evolved in primates, rodents, horses, and some bats, perhaps to support invasive placentation. Placental lactogens occur in rodents and ruminants as well as primates though evolved through duplication of different genes and with functions that only partially overlap. There are also placental hormones, such as the pregnancy-associated glycoproteins of ruminants, that have no equivalent in human gestation. This review focusses on the evolution of placental hormones involved in recognition and maintenance of pregnancy, in maternal adaptations to pregnancy and lactation, and in facilitating immune tolerance of the fetal semiallograft. The contention is that knowledge gained from laboratory and domesticated mammals can translate to a better understanding of human placental endocrinology, but only if viewed in an evolutionary context.

Pregnancy-specific glycoproteins: evolution, expression, functions and disease associations.

Pregnancy-specific glycoproteins (PSGs) are members of the immunoglobulin superfamily and are closely related to the predominantly membrane-bound CEACAM proteins. PSGs are produced by placental trophoblasts and secreted into the maternal bloodstream at high levels where they may regulate maternal immune and vascular functions through receptor binding and modulation of cytokine and chemokine expression and activity. PSGs may have autocrine and paracrine functions in the placental bed, and PSGs can activate soluble and extracellular matrix bound TGF-β, with potentially diverse effects on multiple cell types. PSGs are also found at high levels in the maternal circulation, at least in human, where they may have endocrine functions. In a non-reproductive context, PSGs are expressed in the gastrointestinal tract and their deregulation may be associated with colorectal cancer and other diseases. Like many placental hormones, PSGs are encoded by multigene families and they have an unusual phylogenetic distribution, being found predominantly in species with hemochorial placentation, with the notable exception of the horse in which PSG-like proteins are expressed in the endometrial cups of the epitheliochorial placenta. The evolution and expansion of PSG gene families appear to be a highly active process, with significant changes in gene numbers and protein domain structures in different mammalian lineages and reports of extensive copy number variation at the human locus. Against this apparent diversification, the available evidence indicates extensive conservation of PSG functions in multiple species. These observations are consistent with maternal-fetal conflict underpinning the evolution of PSGs.

Effects of Pregnancy-Specific Glycoproteins on Trophoblast Motility in Three-Dimensional Gelatin Hydrogels.

Trophoblast invasion is a complex biological process necessary for establishment of pregnancy; however, much remains unknown regarding what signaling factors coordinate the extent of invasion. Pregnancy-specific glycoproteins (PSGs) are some of the most abundant circulating trophoblastic proteins in maternal blood during human pregnancy, with maternal serum concentrations rising to as high as 200-400 μg/mL at term. Here, we employ three-dimensional (3D) trophoblast motility assays consisting of trophoblast spheroids encapsulated in 3D gelatin hydrogels to quantify trophoblast outgrowth area, viability, and cytotoxicity in the presence of PSG1 and PSG9 as well as epidermal growth factor and Nodal. We show PSG9 reduces trophoblast motility whereas PSG1 increases motility. Further, we assess bulk nascent protein production by encapsulated spheroids to highlight the potential of this approach to assess trophoblast response (motility, remodeling) to soluble factors and extracellular matrix cues. Such models provide an important platform to develop a deeper understanding of early pregnancy.

Loss of imprinting of the Igf2-H19 ICR1 enhances placental endocrine capacity via sex-specific alterations in signalling pathways in the mouse.

ABSTRACTImprinting control region (ICR1) controls the expression of the Igf2 and H19 genes in a parent-of-origin specific manner. Appropriate expression of the Igf2-H19 locus is fundamental for normal fetal development, yet the importance of ICR1 in the placental production of hormones that promote maternal nutrient allocation to the fetus is unknown. To address this, we used a novel mouse model to selectively delete ICR1 in the endocrine junctional zone (Jz) of the mouse placenta (Jz-ΔICR1). The Jz-ΔICR1 mice exhibit increased Igf2 and decreased H19 expression specifically in the Jz. This was accompanied by an expansion of Jz endocrine cell types due to enhanced rates of proliferation and increased expression of pregnancy-specific glycoprotein 23 in the placenta of both fetal sexes. However, changes in the endocrine phenotype of the placenta were related to sexually-dimorphic alterations to the abundance of Igf2 receptors and downstream signalling pathways (Pi3k-Akt and Mapk). There was no effect of Jz-ΔICR1 on the expression of targets of the H19-embedded miR-675 or on fetal weight. Our results demonstrate that ICR1 controls placental endocrine capacity via sex-dependent changes in signalling.

African locus reduces the effect of ApoE ε4 allele in Alzheimer's disease.

Strong associations between ApoE ε4 and Alzheimer disease (AD) risk have been confirmed worldwide, but there is variability in the effect size across populations. African (AF)-descent populations have a lower risk from ApoE ε4 compared to other populations. Studies in admixed populations showed that the AF ancestral background surrounding the ApoE gene reduces the ε4 risk allele effect. Our aim in this study is to identify genetic loci that show a protective effect in AF ancestral background. Primary analyses included imputed data from 6,417 African American (AA) individuals (Kunkle et al. 2020). We estimated global ancestry using a PC-AiR approach that is robust to known and cryptic relatedness. To identify any protective factors interacting with ApoE in the AF local ancestry region, we performed association analyses using a logistic regression model with ApoE ε4 allele as an interaction term and adjusted for genome-wide ancestry, age, and sex. We performed replication analysis using Whole Genome Sequence (WGS) data on 837 African LA ancestry individuals from Ibadan/Nigeria. We identified a locus (rs10423769) that lies within a large cluster of pregnancy specific beta-1 glycoproteins on chromosome 19, ∼ 2 mB from ApoE, with a significant interaction with the ApoE ε4 allele (β=-0.53; SE=0.12;p-value=1.2x10-5 ; FDR adjusted p-value<0.05) in the logistic regression model in the imputed AA samples. We replicated the association in the Nigerian population (β=-1.35; SE=0.52;p-value=9.6x10-3 ). The epistatic interaction reduced the ApoE ε4 allele risk in AD individuals. This study identifies a new locus that reduces the risk effect of ApoE ε4 in AD in AF. rs10423769 is a common allele in AF-descent populations (minor allele frequency (MAF) = 0.12), rare in Europeans (MAF = 0.003) and monomorphic in East Asians. Our results confirm that the AF ancestral background surrounding the ApoE gene harbors protective factors that help mitigate the effect of the detrimental ε4 allele.

Identification of KLF6/PSGs and NPY-Related USF2/CEACAM Transcriptional Regulatory Networks via Spinal Cord Bulk and Single-Cell RNA-Seq Analysis.

Background To further understand the development of the spinal cord, an exploration of the patterns and transcriptional features of spinal cord development in newborn mice at the cellular transcriptome level was carried out. Methods The mouse single-cell sequencing (scRNA-seq) dataset was downloaded from the GSE108788 dataset. Single-cell RNA-Seq (scRNA-Seq) was conducted on cervical and lumbar spinal V2a interneurons from 2 P0 neonates. Single-cell analysis using the Seurat package was completed, and marker mRNAs were identified for each cluster. Then, pseudotemporal analysis was used to analyze the transcription changes of marker mRNAs in different clusters over time. Finally, the functions of these marker mRNAs were assessed by enrichment analysis and protein-protein interaction (PPI) networks. A transcriptional regulatory network was then constructed using the TRRUST dataset. Results A total of 949 cells were screened. Single-cell analysis was conducted based on marker mRNAs of each cluster, which revealed the heterogeneity of neonatal mouse spinal cord neuronal cells. Functional analysis of pseudotemporal trajectory-related marker mRNAs suggested that pregnancy-specific glycoproteins (PSGs) and carcinoembryonic antigen cell adhesion molecules (CEACAMs) were the core mRNAs in cluster 3. GSVA analysis then demonstrated that the different clusters had differences in pathway activity. By constructing a transcriptional regulatory network, USF2 was identified to be a transcriptional regulator of CEACAM1 and CEACAM5, while KLF6 was identified to be a transcriptional regulator of PSG3 and PSG5. This conclusion was then validated using the Genotype-Tissue Expression (GTEx) spinal cord transcriptome dataset. Conclusions This study completed an integrated analysis of a single-cell dataset with the utilization of marker mRNAs. USF2/CEACAM1&5 and KLF6/PSG3&5 transcriptional regulatory networks were identified by spinal cord single-cell analysis.

Proteomic Analysis of Peripheral Blood in Pregnant Women with Preterm Premature Rupture of Membranes

Background: Preterm Premature Rupture of Membranes (PPROM) is an important obstetric complication faced by modern maternal and foetal medicine and accounts for 30% of all preterm births. At present, it has been reported that there are no clear biomarkers that can accurately predict PPROM. Therefore, there is an urgent need to identify new biomarkers revealing this condition. Objective and Methods: This study aimed to identify differentially expressed proteins in peripheral blood between women with PPROM (n=5) and women with term delivery (n=5). Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) combined with label-free proteomics methods was used to distinguish differential expression between the pooled groups. Go analysis, KEGG pathway analysis and PPI interaction analysis were used to identify key proteins and their potential functions and mechanisms in PPROM. Results: Proteins that were significantly increased with PPROM included the following: retinoic acid receptor reactive protein 2, complement factor D, extracellular matrix protein 1, and von Willebrand factor. In contrast, adhesion G protein coupled receptor G6 (fragment), fibrinogen 2, fibrinogen 3, C3/C5 invertase and pregnancy-specific glycoprotein 6 were significantly reduced. These proteins have known biological functions in the reproduction, vesicle mediated transport, embryo development and aging promoting membrane rupture, which may play important roles in the physiological and pathological processes of preterm premature rupture of membranes and provide a theoretical basis for predicting candidate biomarkers of preterm premature rupture of membranes.