Glycoproteins fetal

Smit, J. W., Huisman, M. T., van Tellingen, O., Wiltshire, H. R., Schinkel, A. H., Absence or pharmacological blocking of placental P-glycoprotein profoundly increases fetal drug exposure, J. Clin. Invest. 1999, 104, 1441-1447. 

Neeser and Schweizer introduced 4 M CF3CO2H for 1 h at 121° for hydrolysis of glycoproteins. Both neutral and amino sugars were considered. They compared this method to hydrolysis with 0.6 M hydrochloric acid for 4 h at 100° and 3 M hydrochloric acid for 0.75 h at 125°. Hydrolysis of fetal-calf-serum fetuin, bovine submaxillary mucin, and horse-radish peroxidase showed hydrolysis with CF3CO2H to be superior. 

CEA is a heterogeneous glycoprotein of molecular weight 180,000 kDa. It was originally considered to be specific for colon carcinoma however, it is now known to be expressed in many different tumors and fetal tissues as well as adult colonic mucosa (27). Table 6 shows a summary of CEA reactivity in epithelial tumors. 

A second characteristic of cancer cells is that they usually appear less differentiated than the tissues from which they arise and are more like embryonic cells. Many cancers produce ectopic proteins, proteins inappropriate to the tissue involved and often identical to proteins synthesized by embryonic or fetal cells. A well-known example is a-fetoprotein, a 72-kDa glycoprotein normally present in serum in almost undetectable amounts but present in large amounts when some types of cancer are present/ A third property of cancers is the tendency toward metastasis, the detachment of cells from the cancer and their development in distant parts of the body. -1... 

Smit JW, Huisman MT, van Telbngen O. Absence or pharmacological blocking of placental P-glycoprotein profoundly increases fetal drug exposure. J Clin Invest 1999 104 1441-1447. 

The strategy used to perform the PMP oligosaccharide profile analysis, with the use of bovine fetuin as a model system, is given in Scheme 1. Bovine fetuin, a major glycoprotein in fetal calf serum, has been widely used as a model for the study of glycoprotein structure. This glycoprotein contains both N- and O-linked oligosaccharides and detailed structural information is available (9-11). 

Huisman MT, Smit JW, Wiltshire HR, Hoetelmans RM, Beijnen JH, Schinkel AE1. 2001. P-glycoprotein limits oral availabilty, brain and fetal penetration of saquinavir even with high doses of ritonavir. Mol. Pharmacol. 59(4) 806-13... 

Erythropoietin is a glycoprotein hormone that regulates red blood cell production in a feedback loop manner between kidney and bone marrow based on oxygen tension. It consists of 165 amino acids and has a molecular weight of 30,000-34,000 approximately 30% is accounted for by covalently linked carbohydrate. Erythropoietin is produced by the fetal liver and shortly after birth production switches from the liver to the kidney. In the fetus, erythropoietin functions in a paracrine-endocrine fashion because liver is the site of erythropoietin synthesis as well as ery-thropoiesis. The mechanism of this developmental switch is unclear. In the liver, erythropoietin synthesis occurs in... 

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