What are cytotrophoblast cells?
Cytotrophoblasts and syncytiotrophoblasts. Trophoblasts (from Greek to feed: threphein) are cells forming the outer layer of a blastocyst, which provides nutrients to the embryo, and develops into a large part of the placenta.
What is the role of the cytotrophoblast?
The primary function of the endovascular cytotrophoblast is to penetrate maternal spiral arteries and route the blood flow through the placenta for the growing embryo to use.
What are the differences between cytotrophoblast and syncytiotrophoblast?
The syncytiotrophoblast is a rapidly growing multinucleated mass, which invades and ruptures endometrial capillaries forming lacunae. The cytotrophoblast is a layer of mononucleated cells, which invades the syncytiotrophoblast matrix and forms early chorionic villi.
What are villous trophoblasts?
Villous trophoblasts cover the chorionic villi and are involved in the exchange of gas and nutriments between the mother and the fetus. Extravillous trophoblasts invade deep into the uterus wall (as far as the myometrium) and are directly implicated in the anchoring of chorionic villi in the uterus.
What are syncytiotrophoblast cells?
Syncytiotrophoblast (from the Greek ‘syn’- “together”; ‘cytio’- “of cells”; ‘tropho’- “nutrition”; ‘blast’- “bud”) is the epithelial covering of the highly vascular embryonic placental villi, which invades the wall of the uterus to establish nutrient circulation between the embryo and the mother.
Does cytotrophoblast produce hCG?
Cytotrophoblast cells naturally produce hyperglycosylated hCG, which promotes their growth and invasion. Other cells need to be transformed to produce invasive hyperglycosylated hCG.
What are Syncytiotrophoblast cells?
What are decidual cells?
Decidual cells are a distinctive cell population observed in the mammalian endometrium during pregnancy. Their appearance can also be induced with appropriate stimuli in the hormone-primed pseudopregnant uterus.
Does Cytotrophoblast produce hCG?
Does syncytiotrophoblast produce progesterone?
The syncytiotrophoblast produces both protein and steroid hormones which are released into the maternal blood (M). Beginning at about eight weeks of gestation, the syncytiotrophoblast assumes the role of the corpus luteum and begins to secrete the steroid hormones, estrogen and progesterone.
What hormone do cytotrophoblast cells produce at high amounts before parturition?
Cytotrophoblast and syncytiotrophoblast cells make excess amounts of hCG and hyperglycosylated hCG.
What is Hyperglycosylated hCG?
Hyperglycosylated hCG (hCG-H) is a glycoprotein with the same polypeptide structure as hCG, and much larger N- and O-linked oligosaccharides. The oligosaccharides increase the molecular weight of hCG from 36,000 – 37,000 u to 40,000 – 41,000 u, depending on the extent of hyperglycosylation.
What is villous syncytiotrophoblast?
The villous syncytiotrophoblast is a terminally differentiated, mitotically inactive cell type, with amphophilic to eosinophilic cytoplasm and multiple small, hyperchromatic nuclei.
How does a cytotrophoblastic stem cell differentiate into a syncytiotrophoblast?
An undifferentiated cytotrophoblastic stem cell will differentiate into a villous cytotrophoblast, which is what constitutes primary chorionic villi, and will eventually coalesce into villous syncytiotrophoblast. The formation of syncytiotrophoblast from cytotrophoblast is a terminal differentiation step of trophoblastic cells.
What are cytotrophoblasts composed of?
Cytotrophoblasts, the inner layer of villous trophoblasts, are composed of proliferative stemlike cells, characterized by expression of p63.
Where is the cytotrophoblast located in the developing embryo?
Cytotrophoblast. It is interior to the syncytiotrophoblast and external to the wall of the blastocyst in a developing embryo. The cytotrophoblast is considered to be the trophoblastic stem cell because the layer surrounding the blastocyst remains while daughter cells differentiate and proliferate to function in multiple roles.