Differential expression of occludin splice variants in human placental vasculature in pregnancies complicated with gestational diabetes

s / Placenta 57 (2017) 225e335 302 of fusion events. Env-deficient HIV-1-based viruses pseudotyped with Syn-2 were next produced to specifically assess the impact of Gal-1 on Syn-2. As expected, Syn-2-positive pseudotypes were more infectious toward MFSD2a-expressing 293T cells in comparison to parental cells. Importantly, addition of gal-1 to Syn-2-pseudotyped viruses significantly increased infection when compared to non-treated cells or cells infected with control viruses (no envelope or with the VSV envelope). Furthermore, the gal1-dependent increase in infection was blocked by lactose, and no equivalent increase in infectivity was observed upon the addition of gal-3. Finally, by spinoculation experiments at 4 C, we also confirmed that gal-1 enhances infectivity of Syn-2 pseudoviruses by increasing their binding of to the cell surface. Our study establishes for the first time a functional link between two important actors of trophoblastic cells fusion, Syn-2 and gal1. Syn-2 could thus benefit from the binding activity of gal-1 to optimize and regulate its interaction with its cellular receptor during vCTB fusion. http://dx.doi.org/10.1016/j.placenta.2017.07.246 P2.30. DIFFERENTIAL EXPRESSION OF OCCLUDIN SPLICE VARIANTS IN HUMAN PLACENTAL VASCULATURE IN PREGNANCIES COMPLICATED WITH GESTATIONAL DIABETES Stephany Villota, Lopa Leach, Maria Toledo-Rodriguez. The University of Nottingham, Nottingham, UK Introduction: Occludin (OCLN) is a transmembrane tight junctional protein which contains two extracellular loops required for stable adhesion and a cytoplasmic tail that allows signalling. NCBI database reports three mRNAOCLN splice variants. Variants 1 and 2 translate into a fully functional isoform A (~60 kDa; full length), while variant 3 translates into a truncated isoform B (~30 kDa; cytoplasmic tail only) which cannot translocate to tight junctions. Differential expression of OCLN isoforms A and B could explain changes in junctional occupancy of OCLN, as evidenced by the decreased immunolocalization in the vasculature of gestational diabetic (GDM) placentae. Objectives: Determine the expression of OCLN splice variants and protein isoforms in GDM placental vasculature Methods: Placental villous samples (full term) were obtained from normal (n1⁄4 9), and GDM pregnancies where glucose levels were controlled by diet (n1⁄4 6) or metformin (n1⁄4 5). qPCR amplification and immunoblotting were used to determine gene expression of OCLN splice variants and protein isoforms. Results: OCLN variant 1 gene expressionwas lower in GDM-diet samples (p < 0.05). OCLN variant 2 gene expression was lower in GDM-diet and metformin samples (p < 0.01). Additionally, the protein expression of isoform Awas lower in GDM-diet samples. Protein expression of isoform B increased in GDM samples. Conclusion: Our data suggests that GDMmay affect both gene and protein expression of OCLN, with treatment regime having a differential effect on protein expression. The decrease of protein isoform A, combined with an increase of isoform B, may be responsible for the reduced localization of OCLN in tight junctions. http://dx.doi.org/10.1016/j.placenta.2017.07.247 P2.31. MOLECULAR ANALYSES REVEAL ATYPICAL CONFINED PLACENTAL MOSAICISM WITH A SMALL SUPERNUMERARY MARKER CHROMOSOME DERIVED FROM CHROMOSOME 18: A CASE REPORT OF DISCORDANT RESULTS OF THREE PRENATAL TESTS Taisuke Sato , Osamu Samura , Kazuhiro Kajiwara , Ken Takahashi , Hiroaki Aoki , Noriko Kato , Kosuke Taniguchi , Masaki Yoshida , Ohsuke Migita , Aikou Okamoto , Kenichiro Hata . Department of Obstetrics and Gynecology, The Jikei University School of Medicine, Tokyo, Japan; Department of Maternal-Fetal Biology, National Center Institute for Child Health and Development, Tokyo, Japan; GeneTech, Inc., Tokyo, Japan Objective: Three prenatal tests on the members of a family showed discordant results; we performed molecular analyses to investigate the causes of this discordance. Case and Method: Non-invasive prenatal testing (NIPT) was performed on a 41-year old Japanese woman at 10 weeks of gestation, and the result revealed trisomy 18. There was a high possibility that the fetus might also have primary trisomy 18. Therefore, amniocentesis was performed at 16 weeks of gestation. However, the result showed 47,XX,+mar [16]/47,XX,+18 [2]. At 19 weeks of gestation, ultrasonic examination revealed no abnormalities. After adequate genetic counseling, the patient and her partner chose termination of pregnancy at 20 weeks of gestation. The newborn showed no malformations at birth. To detect the causes of the discordance in results, we performed fluorescence in situ hybridization (FISH) analysis on cultured amniotic cells fixed with Carnoy solution and genome-wide single nucleotide polymorphism (SNP) array analysis on the umbilical cord DNA (both parent and placental DNA). Results: The karyotype of neither parent showed small supernumerary marker chromosomes (sSMC). FISH analysis with D18Z1 probe detected positive signals for sSMCs in most of the analyzed amniotic cells. Furthermore, the SNP array analysis of umbilical cord DNA revealed maternal disomy in the entire chromosome 18, with approximately 245 Mb of copy-neutral loss of heterozygosity, including in the centromere region. In contrast, SNP array analysis of the placental DNA showed a pattern most likely to be primary trisomy 18. Thus, there was discordance in the abundance of trisomy 18 cells in the fetus and the placental chorionic villi, due to incomplete trisomy rescue. Conclusion: We reported a clinically impressive case with discordant results from three different prenatal tests. Molecular analyses revealed that the results of these prenatal tests were precisely reflected in the characteristics of the corresponding material examined. http://dx.doi.org/10.1016/j.placenta.2017.07.248 P2.33. IMPACT OF MATERNAL DEPRESSION AND EXPOSURE TO NATURAL DISASTER ON PLACENTAL GENE EXPRESSION Jackie Finik , Jessica Buthmann , Wei Zhang , Yoko Nomura . CUNY School of Public Health, New York, NY, USA; CUNY Queens College, Flushing, NY, USA; CUNY Graduate Center, New York, NY, USA; 4 Icahn School of Medicine at Mount Sinai, New York, NY, USA Objectives: Prenatal stress can alter HPA axis functioning in offspring via the placenta, which regulates the exchange of hormones between mother and fetus. Key genes involved in this exchange include HSD11B2 and SLC6A4. Dysregulation in HSD11B2 and SLCA4 expression may expose the developing fetus to higher levels of cortisol and serotonin, which has been linked with suboptimal neurobehavioral trajectories. Methods: The present study utilized 293 placentas collected by the Stress in Pregnancy (SIP) study, an on-going longitudinal birth cohort study in New York City. Participants were recruited during their 2nd trimester (i.e., baseline), and followed throughout their pregnancy and as their children develop. A subset of the cohort was exposed to Superstorm Sandy during pregnancy. Maternal depressive symptomatology was assessed via selfreport (Edinburgh Postnatal Depressive Scale) at baseline. Placenta tissue samples were collected following participant births, and subsequently, gene expression of HSD11B2 and SLC6A4 was quantified using qPCR. Results: Results of an Analysis of Co-Variance (ANCOVA) adjusted for maternal age, education, and race/ethnicity examined the main effects and interaction of depression and Sandy exposure during pregnancy on placental gene expression. We found that both HSD11B2 and SLC6A4 were hypoexpressed in those exposed to Sandy (p1⁄4.001; p1⁄4.002, respectively). No significant differences in expression by depression status or notable interaction effects were observed. However, pairwise comparisons revealed that both the unaffected and comorbid groups had higher levels Abstracts / Placenta 57 (2017) 225e335 303s / Placenta 57 (2017) 225e335 303 of HSD11B2 and SLC6A4 expression (p<.001, p1⁄4.001, respectively) as compared to the depressed only group. Conclusion: These findings indicate that observed stress (i.e., Superstorm Sandy exposure) and perceived stress (i.e., depressive symptomatology) may differentially influence underlying biological mechanisms. Enhanced understanding of the underlying biological pathways by which maternal stress (objective and subjective) impacts fetal/child development can help improve identification and intervention for affected mothers and their offspring. http://dx.doi.org/10.1016/j.placenta.2017.07.249 P2.34. CHARACTERISATION OF EARLY PREGNANCY DEPENDENT GENE EXPRESSION CHANGES IN THE UTERINE ARTERY OF HYPERTENSIVE AND NORMOTENSIVE RATS Hannah Morgan, Elisabeth Beattie, Martin McBride, Delyth Graham. Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK Objectives: Hypertensive complications of pregnancy are associated with impaired uteroplacental remodelling and reduced placental perfusion. Stroke prone spontaneously hypertensive (SHRSP) rats demonstrate reduced uteroplacental blood flow in late pregnancy. This study investigated the causative effects of early pregnancy on the uterine artery transcriptome profile in SHRSP and normotensive Wistar Kyoto (WKY) rats. Methods: SHRSP and WKY 12-week-old females were time mated and uterine arteries (UA) isolated at gestational day (GD)6 (n1⁄43). Non-pregnant (NP) UAwere isolated from virgin aged-matched controls (n1⁄43). UA RNAseq (Illumina platform) was performed and transcript changes were interpreted using Ingenuity Pathway Analysis (FDR < 0.05, FPKM>1.0). Quantitative RTPCR was used to validate significantly differentially expressed genes. Results: The pregnancy-dependent transcript profile of SHRSP had more differentially expressed genes compared toWKY (796 vs 535), with 147 gene changes common to pregnancy. Pathway analysis revealed gene expression differences in response to pregnancy in WKY and SHRSP. In the NP v GD6 comparison, gene expression changes in the a-adrenergic pathwa