The low success rate of somatic nuclear transfer (NT) is hypothesized to be mainly due to functional defects in the trophoblast cell lineage rather than the inner cell mass (ICM); this hypothesis, however, remains to be tested directly. Here we separated the ICMs from cloned blastocysts and aggregated the cloned ICM with two fertilization-derived (FD) tetraploid (4N) embryos. We found that the ...

IGF-I and IGF-II were appeared to play major roles in the adhesive and migratory events that are considered to be crucial in the implantation process. The purpose of this study was to determine the effects of IGF-I on trophoblast adhesion to extracellular matrix. Trophoblast cells obtained from early gestation at artificial abortion were incubated with the indicated doses of IGF-I at the indica...

Chorionic gonadotropin (CG) is indispensable for human pregnancy because it controls implantation, decidualization, and placental development. However, its particular role in the differentiation process of invasive trophoblasts has not been fully unraveled. Here we demonstrate that the hormone promotes trophoblast invasion and migration in different trophoblast model systems. RT-PCR and Western...

The placenta has been the subject of extensive basic research efforts in two distinct fields. The developmental biology of placenta has been studied because it is the first organ to develop during embryogenesis and because a number of different gene mutations in mice result in embryonic lethality due to placental defects. The trophoblast cell lineage is relatively simple such that only two majo...

Trophoblast-specific expression of the human alpha-subunit glycoprotein hormone gene requires a tightly linked array of five different regulatory elements [trophoblast-specific element (TSE), alpha-activating element (alphaACT), a tandem cAMP response element (CRE), junctional regulatory element (JRE), and a CCAAT box]. We examined their contextual contributions to trophoblast-specific expressi...

BACKGROUND Fetal cells are shed from the regressing chorionic villi and it is possible to retrieve extravillous cytotrophoblast cells by transcervical sampling. The abundance of trophoblast cells in transcervical samples suggests that this non-invasive approach could distinguish between normal and abnormal pregnancies, such as an ectopic pregnancy (EP) and blighted ovum (BO). We aim to identify...

The trophoblast, which is derived from the extraembryonic trophectoderm, is the first cells differentiated from the preimplantation mammalian embryos. In this regard, two differentiation pathways are critical for the survival and development of the embryo in utero. In the first one, cytotrophoblasts (CTBs) fuse into a layer of syncytiotrophoblasts that covers the chorionic villi. These cells ar...

The process of implantation and placentation in women in volves a series of intercellular interactions, the eventual elucidation of which will result in extensions or even shifts of cell biological paradigms. These include the formation of motile and non-motile mononuclear and multinuclear trophoblast, alterations between faster and slower states of proliferation, changes in adhesive properties...

It has been postulated that the transplacental passage of maternal iron to the developing fetus requires binding of maternal transferrin to the trophoblast. We have therefore examined the ability of the human placenta to bind transferrin in vitro. Transferrin was demonstrated on trophoblast of human chorionic villi by immunohistologic methods. Moreover, after removal of transferrin bound in viv...

Imprinted genes play important roles in placenta development and function. Parthenogenetic embryos, deficient in paternally expressed imprinted genes, lack extra-embryonic tissues of the trophoblast lineage. Parthenogenetic trophoblast stem cells (TSCs) are extremely difficult to derive, suggesting that an imprinted gene(s) is necessary for TSC establishment or maintenance. In a candidate study...