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Study Question: Does glycodelin-A (GdA) induce conversion of human peripheral blood CD16-CD56bright natural killer (NK) cells to decidual NK (dNK) cells to facilitate placentation?Summary Answer: GdA binds to blood CD16-CD56bright NK cells via its sialylated glycans and converts them to a dNK-like cells, which in turn regulate endothelial cell angiogenesis and trophoblast invasion via vascular endothelial growth factor (VEGF) and insulin-like growth factor-binding protein 1 (IGFBP-1) secretion, respectively.What Is Known Already: dNK cells are the most abundant leucocyte population in the decidua. These cells express CD16-CD56bright phenotype. Peripheral blood CD16-CD56bright NK cells and hematopoietic precursors have been suggested to be capable of differentiating towards dNK cells upon exposure to the decidual microenvironment. These cells regulate trophoblast invasion during spiral arteries remodelling and mediate homoeostasis and functions of the endothelial cells. GdA is an abundant glycoprotein in the human decidua with peak expression between the 6th and 12th week of gestation, suggesting a role in early pregnancy. Indeed, GdA interacts with and modulates functions and differentiation of trophoblast and immune cells in the human feto-maternal interface. Aberrant GdA expression during pregnancy is associated with unexplained infertility, pregnancy loss and pre-eclampsia.Study Design, Size, Duration: CD16+CD56dim, CD16-CD56bright and dNK cells were isolated from human peripheral blood and decidua tissue, respectively, by immuno-magnetic beads or fluorescence-activated cell sorting. Human extravillous trophoblasts were isolated from first trimester placental tissue after termination of pregnancy. Biological activities of the cells were studied after treatment with GdA at a physiological dose of 5 μg/mL. GdA was purified from human amniotic fluid by immuno-affinity chromatography.Participants/materials, Setting, Methods: Expression of VEGF, CD9, CD49a, CD151 and CD158a in the cells were determined by flow cytometry. Angiogenic proteins in the spent media of NK cells were determined by cytokine array and ELISA. Blocking antibodies were used to study the functions of the identified angiogenic proteins. Endothelial cell angiogenesis was determined by tube formation and trans-well migration assays. Cell invasion and migration were determined by trans-well invasion/migration assay. Binding of normal and de-sialylated GdA, and expression of L-selectin and siglec-7 on the NK cells were analysed by flow cytometry. The association between GdA and L-selectin on NK cells was confirmed by immunoprecipitation. Extracellular signal-regulated protein kinases (ERK) activation was determined by Western blotting and functional assays.Main Results and the Role Of Chance: GdA treatment enhanced the expression of dNK cell markers CD9 and CD49a and the production of the functional dNK secretory product VEGF in the peripheral blood CD16-CD56bright NK cells. The spent media of GdA-treated CD16-CD56bright NK cells promoted tube formation of human umbilical vein endothelial cells and invasiveness of trophoblasts. These stimulatory effects were mediated by the stimulatory activities of GdA on an ERK-activation dependent production of VEGF and IGFBP-1 by the NK cells. GdA had a stronger binding affinity to the CD16-CD56bright NK cells as compared to the CD16+CD56dim NK cells. This GdA-NK cell interaction was reduced by de-sialylation. GdA interacted with L-selectin, expressed only in the CD16-CD56bright NK cells, but not in the CD16+CD56dim NK cells. Anti-L-selectin functional blocking antibody suppressed the binding and biological activities of GdA on the NK cells.Large Scale Data: N/A.Limitations, Reasons For Caution: Some of the above findings are based on a small sample size of peripheral blood CD16-CD56bright NK cells. These results need to be confirmed with human primary dNK cells.Wider Implications Of the Findings: This is the first study on the biological role of GdA on conversion of CD16-CD56bright NK cells to dNK-like cells. Further investigation on the glycosylation and functions of GdA will enhance our understanding on human placentation and placenta-associated complications with altered NK cell biology.Study Funding/competing Interest(s): This work was supported by the Hong Kong Research Grant Council Grant 17122415, Sanming Project of Medicine in Shenzhen, the Finnish Cancer Foundation, Sigrid Jusélius Foundation and the Finnish Society of Clinical Chemistry. The authors have no competing interests to declare. [ABSTRACT FROM AUTHOR]

Study Question: Can human embryonic stem cell-derived trophoblastic spheroids be used to study the early stages of implantation?Summary Answer: We generated a novel human embryonic stem cell-derived trophoblastic spheroid model mimicking human blastocysts in the early stages of implantation.What Is Known Already: Both human embryos and choriocarcinoma cell line derived spheroids can attach onto endometrial cells and are used as models to study the early stages of implantation. However, human embryos are limited and the use of cancer cell lines for spheroid generation remains sub-optimal for research.Study Design, Size, Duration: Experimental induced differentiation of human embryonic stem cells into trophoblast and characterization of the trophoblast.Participants/materials, Setting, Methods: Trophoblastic spheroids (BAP-EB) were generated by inducing differentiation of a human embryonic stem cell line, VAL3 cells with bone morphogenic factor-4, A83-01 (a TGF-β inhibitor), and PD173074 (a FGF receptor-3 inhibitor) after embryoid body formation. The expressions of trophoblastic markers and hCG levels were studied by real-time PCR and immunohistochemistry. BAP-EB attachment and invasion assays were performed on different cell lines and primary endometrial cells.Main Results and the Role Of Chance: After 48 h of induced differentiation, the BAP-EB resembled early implanting human embryos in terms of size and morphology. The spheroids derived from embryonic stem cells (VAL3), but not from several other cell lines studied, possessed a blastocoel-like cavity. BAP-EB expressed several markers of trophectoderm of human blastocysts on Day 2 of induced differentiation. In the subsequent days of differentiation, the cells of the spheroids differentiated into trophoblast-like cells expressing trophoblastic markers, though at levels lower than that in the primary trophoblasts or in a choriocarcinoma cell line. On Day 3 of induced differentiation, BAP-EB selectively attached onto endometrial epithelial cells, but not other non-endometrial cell lines or an endometrial cell line that had lost its epithelial character. The attachment rates of BAP-EB was significantly higher on primary endometrial epithelial cells (EEC) taken from 7 days after hCG induction of ovulation (hCG+7 day) when compared with that from hCG+2 day. The spheroids also invaded through Ishikawa cells and the primary endometrial stromal cells in the co-culture.Limitations, Reasons For Caution: The attachment rates of BAP-EB were compared between EEC obtained from Day 2 and Day 7 of the gonadotrophin stimulated cycle, but not the natural cycles.Wider Implications Of the Findings: BAP-EB have the potential to be used as a test for predicting endometrial receptivity in IVF cycles and provide a novel approach to study early human implantation, trophoblastic cell differentiation and trophoblastic invasion into human endometrial cells. [ABSTRACT FROM AUTHOR]

BACKGROUND: High serum estradiol (E2) levels following ovarian stimulation lead to reduced implantation and pregnancy rates, yet the underlying mechanisms remain unknown. We investigated if aberrant expression of genes in the Wnt-signaling pathway may be involved. [ABSTRACT FROM PUBLISHER]

Background: Obese women require higher gonadotrophin doses for ovarian stimulation and to trigger ovulation. The bioavailability of a drug is affected by its route of administration. Herein, the bioavailability of hCG was compared after intramuscular (i.m.) or subcutaneous (s.c.) injection in obese and non-obese women.Methods: Twenty four Chinese women, 12 with a body mass index (BMI) >/==" BORDER="0">28 kg/m(2) and 12 with a BMI of 20-25 kg/m(2) were recruited as the obese and non-obese groups respectively. A single hCG injection was given intramuscularly on one occasion, and subcutaneously on a second occasion, separated by 4 weeks. Blood samples were taken at intervals for the pharmacokinetic study of hCG.Results: Examination of the hCG plasma concentration-time curve showed the area under the curve (AUC) and maximum concentration (C(max)) of hCG to be significantly higher after i.m. injection than after s.c. injection in both the obese and non-obese groups. However, the AUC and C(max) values in obese women were significantly lower than in non-obese women, irrespective of whether i.m. or s.c. dosing was employed.Conclusions: Intramuscular dosing of hCG provided better bioavailability than s.c. dosing, but bioavailability was significantly less in obese women than in non-obese women. [ABSTRACT FROM AUTHOR]

Background: A combination of mifepristone and misoprostol provides an effective method of medical abortion for early pregnancy. This is the first randomized trial comparing the use of sublingual misoprostol with vaginal misoprostol in combination with mifepristone for termination of early pregnancies up to 63 days.Methods: A total of 224 women who requested legal termination of pregnancy up to 63 days were randomized by computer- generated list into two groups and given 200 mg of oral mifepristone followed 48 h later by either 800 micro g of sublingual (n = 112) or vaginal (n = 112) misoprostol.Results: Complete abortion occurred in 98.2% (95% CI: 93-99) of women in the sublingual group and 93.8% (95% CI: 88-97) in the vaginal group. There were three ongoing pregnancies in the vaginal group but none in the sublingual group. The median duration of vaginal bleeding was 17 days. There was no serious complication. Fever, chills and gastrointestinal side-effects (nausea, vomiting and diarrhoea) were significantly more common in the sublingual group.Conclusions: The combination of mifepristone and misoprostol is effective for medical abortion up to 63 days. Both the sublingual and vaginal are effective routes of administration. Further randomized trials are required to find out the optimal dose of sublingual misoprostol that can give the highest complete abortion rate and lowest incidence of side-effects. [ABSTRACT FROM AUTHOR]