The main goal of this proposal is to generate extravillous trophoblast (EVT) from human embryonic stem cells (hESC) after they have been treated with BMP4 (BMP-hESC) and use them as a model to study EVT emergence, migration, and invasiveness, as well as intrinsic and extrinsic factors that influence these properties. This project has high significance because EVT ultimately become the invasive trophoblast (TR) cells of human placenta that penetrate maternal blood vessels and enhance blood flow. While invasion of the uterine decidua and the proximate inner third of the myometrium by EVT is a characteristic feature of a healthy pregnancy, shallow invasion is associated with placental pathologies, among them pre-eclampsia (PE) and intra-uterine growth retardation (IUGR). PE is a pregnancy-specific syndrome that affects ~ 3 % of pregnancies and is responsible for 15 % of pre-term births and an estimated 50,000 deaths per year worldwide. It is characterized by maternal hypertension, edema, and proteinuria, conditions that in the more serious, early onset disease can manifest as soon as 20 weeks of pregnancy.
Aim 1 will establish and characterize a hESC-derived cell culture model for the study of EVT.
This aim i s based on the hypothesis that the sub-population of HLA-G positive BMP-hESC that migrates through a Matrigel-coated matrix under high oxygen (O2) conditions are EVT homologs. HLA-G positive cells that remain associated with the BMP-hESC colonies under low O2 conditions represent a precursor population of non- invasive EVT whose properties will be distinct from the invasive population captured under high O2 conditions.
Aim 2 will examine the ability of the EVT derived from BMP-hESC to invade through cross-linked, relatively stiff matrices, such as Type I collagen, and to interact with microcapillaries cultured within such matrices.
Aim 3 will examine a possible model for PE in which up-regulation of stable HIF1 alpha (HIF1A) protein is hypothesized to counteract the effects of high O2 during in vitro development of BMP-hESC and retard development into invasive EVT. If time permits or the HIF1A hypothesis proves incorrect, we would plan to study the effects of knockdown of at least one transcription factor that has been implicated in EVT emergence and differentiation, namely ASCL2.
Aim 4 will attempt to re-create EVT from infants born to mothers with PE by generating induced pluripotent stem cells (iPSC) from discarded umbilical cord and converting these pluripotent cells to CT, EVT and other lineages by the BMP4 approach. The properties of these cells can then be compared with EVT generated from cord cells from pregnancies not complicated by PE. The hypothesis underpinning this aim is that some forms of PE are initiated by genetically-based placental pathology, and these abnormalities will be manifested in the phenotype of EVT generated from umbilical cord-derived iPSC. Together, these aims will bring innovative and new approaches to the study of human TR cells and to examining the basis of placental pathologies, especially PE. They will create the first in vitro model that makes possible the study of both the emergence and invasiveness of EVT cells, and the first model to study these early events directly in TR from pregnancies complicated by PE.
This project is designed to establish a new model for studying extravillous trophoblast (EVT), a placental cell type that invades the wall of the womb during the first trimester of pregnancy and whose failure to invade properly can lead to serious consequences for mother and child, including a condition called pre-eclampsia. Instead of isolating the cells from placentae, the goal is to generate EVT from human pluripotent stem cells, thereby allowing us to study factors that control their invasiveness. Also by generating such pluripotent cells from umbilical cords of babies born to mothers that developed pre-eclampsia, we hope to recreate the cell type that caused the disease in the first place.
|Yunusov, Dinar; Anderson, Leticia; DaSilva, Lucas Ferreira et al. (2016) HIPSTR and thousands of lncRNAs are heterogeneously expressed in human embryos, primordial germ cells and stable cell lines. Sci Rep 6:32753|
|Yabe, Shinichiro; Alexenko, Andrei P; Amita, Mitsuyoshi et al. (2016) Comparison of syncytiotrophoblast generated from human embryonic stem cells and from term placentas. Proc Natl Acad Sci U S A 113:E2598-607|
|PrabhuDas, Mercy; Bonney, Elizabeth; Caron, Kathleen et al. (2015) Immune mechanisms at the maternal-fetal interface: perspectives and challenges. Nat Immunol 16:328-34|
|Yang, Ying; Adachi, Katsuyuki; Sheridan, Megan A et al. (2015) Heightened potency of human pluripotent stem cell lines created by transient BMP4 exposure. Proc Natl Acad Sci U S A 112:E2337-46|
|Lee, Kiho; Kwon, Deug-Nam; Ezashi, Toshihiko et al. (2014) Engraftment of human iPS cells and allogeneic porcine cells into pigs with inactivated RAG2 and accompanying severe combined immunodeficiency. Proc Natl Acad Sci U S A 111:7260-5|
|Yang, Penghua; Dai, Aihua; Alexenko, Andrei P et al. (2014) Abnormal oxidative stress responses in fibroblasts from preeclampsia infants. PLoS One 9:e103110|
|Yuan, Ye; Lee, Kiho; Park, Kwang-Wook et al. (2014) Cell cycle synchronization of leukemia inhibitory factor (LIF)-dependent porcine-induced pluripotent stem cells and the generation of cloned embryos. Cell Cycle 13:1265-76|
|Yoshinaga, Koji; PrabhuDas, Mercy; Davies, Christopher et al. (2014) Interdisciplinary collaborative team for blastocyst implantation research: inception and perspectives. Am J Reprod Immunol 71:1-11|
|Roberts, R Michael; Loh, Kyle M; Amita, Mitsuyoshi et al. (2014) Differentiation of trophoblast cells from human embryonic stem cells: to be or not to be? Reproduction 147:D1-12|
|Telugu, B P; Adachi, K; Schlitt, J M et al. (2013) Comparison of extravillous trophoblast cells derived from human embryonic stem cells and from first trimester human placentas. Placenta 34:536-43|
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