Please use this identifier to cite or link to this item: http://scholarbank.nus.edu.sg/handle/10635/53803
Title: FORMATION AND FUNCTION OF INVASIVE SYNCYTIOTROPHOBLAST FROM HUMAN EMBRYONIC STEM CELLS
Authors: NANI DJUNAIDI
Keywords: Embryonic stem cells, Trophoblast, Placenta, Human Implantation
Issue Date: 22-Jan-2014
Citation: NANI DJUNAIDI (2014-01-22). FORMATION AND FUNCTION OF INVASIVE SYNCYTIOTROPHOBLAST FROM HUMAN EMBRYONIC STEM CELLS. ScholarBank@NUS Repository.
Abstract: Outside of some classical morphological images there is very little information on cell types and molecular events of the early post-implantation stages of human development. These stages are referred to as the pre-lacunar period of the trophoblastic plate and the lacunar or pre-villous stages, and exist from the time of embryo implantation to approximately five days post-implantation. The vast majority of cells consist of cytotrophoblast and syncytiotrophoblast cells as a ¿front line¿ with maternal side and in the process of deeply invading into the endometrial stroma. The syncytiotrophoblast that exist during this early implantation period was suggested to be invasive and similar but distinct as compared to the more well-studied villous syncytiotrophoblast, which appears much later on during gestation. While it is virtually impossible to study this period of development directly, with their propensity to give rise to the trophoblast lineage human embryonic stem cells (hESC) provide the opportunity to model these events in a cell culture dish. We and others have shown that a combination of BMP4 induction and FGF receptor inhibition leads hESC to differentiation along the trophoblast lineage. We have combined this with a subsequent High Content Screen (HCS) of growth factors and cytokines to explore the potential of these cells to give rise to trophoblast sub-populations. Specifically, the HCS was initiated on hESC that had first been induced to differentiate/commit to the trophoblast lineage for 3 days of BMP4/SU5402 treatment. Eleven growth factors and cytokines were chosen based on a review of the literature and an examination of receptor expression in mRNA-seq data generated from hESC-derived trophoblast. Over 72 hours and in a 96 well format, whole cell and nuclear stains were utilized to capture cell features (e.g. cytoplasm to nuclear ratios) to determine responses to these growth factors and cytokines. We identified the BMP4, Epidermal Growth Factor (EGF), and Keratinocyte Growth Factor/ Fibroblast Growth Factor 7 (KGF/ FGF7) resulted in increased multinucleated cells. Subsequently when combined, these molecules led to greater that 90% of cells becoming multinuclear. Based on our interest to explore the early trophoblast lineage segregation and investigation of expression in mRNA-seq data generated from hESC-derived trophoblast for possible invasive marker, we firstly describe and suggest that our molecules combination led to the formation of invasive syncytiotrophoblast. We managed to demonstrate the invasive features in this syncytiotrophoblast based on the positive protein expression of active membrane-type matrix metalloproteinase type 1 (MT1-MMP/ MMP14) in integration with Invadopodia formation, which is the main markers for cancer metastasis. This model of hESC-derived invasive syncytiotrophoblast provides an avenue to begin to understand the mechanisms of invasiveness in the implanting human embryo, which we argue, shares features to metastatic cancer cells.
URI: http://scholarbank.nus.edu.sg/handle/10635/53803
Appears in Collections:Ph.D Theses (Open)

Show full item record
Files in This Item:
File Description SizeFormatAccess SettingsVersion 
DjunaidiN.pdf10.75 MBAdobe PDF

OPEN

NoneView/Download

Page view(s)

116
checked on Oct 27, 2018

Download(s)

86
checked on Oct 27, 2018

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.