Placenta stability

Manchester DK, Gordon SK, Golas CL, Roberts EA, Okey AB. Ah receptor in human placenta stabilization by molybdate and characterization of binding of 2,3,7,8-tetrachlorodibenzo-p-dioxin, 3-methylcholanthrene, and benzo(a)-pyrene. Cancer Res 1987 47 4861 -868. 

HSA is used therapeutically as an aqueous solution it is available in concentrated form (15-25 per cent protein) or as an isotonic solution (4-5 per cent protein). In both cases, in excess of 95 per cent of the protein present is albumin. It can be prepared by fractionation from normal plasma or serum, or purified from placentas. The source material must first be screened for the presence of indicator pathogens. After purification, a suitable stabilizer (often sodium caprylate) is added, but no preservative. The solution is then sterilized by filtration and aseptically filled into final sterile containers. The relative heat stability of HSA allows a measure of subsequent heat treatment, which further reduces the risk of accidental transmission of viable pathogens (particularly viruses). This treatment normally entails heating the product to 60 °C for 10 h. It is then normally incubated at 30-32 °C for a further 14 days and subsequently examined for any signs of microbial growth. 

Than, M. E., Henrich, S., Huber, R., Ries, A., Mann, K., Kuhn, K., Timpl, R., Bourenkov, G. P., Bartunik, H. D., and Bode, W. (2002). The 1.9-A crystal structure of the non-collagenous (NCI) domain of human placenta collagen IV shows stabilization via a novel type of covalent Met-Lys cross-link. Proc. Natl. Acad. Sci. USA 99, 6607-6612. 

The distribution of soluble arylsulphatases in human tissues has been examined via ion-exchange chromatography. All tissues contained arylsulphatase A and B. In addition, brain singularly contained significant quantities of a minor anionic form (Bm) only trace amounts of Bm were found in liver, kidney, testis, and placenta. Arylsulphatases B and Bm had equal activity towards methylumbelliferyl sulphate, nitrocatechol sulphate, and UDP-2-acetamido-2-deoxy-D-galactose 4-sulphate, but both forms were inactive toward the arylsulphatase A substrates cerebroside sulphate and L-ascorbic acid 2-sulphate. The physicochemical properties of arylsulphatases B and Bm differed with respect to thermal stability, ionicity, and behaviour on polyacrylamide gel electrophoresis and isoelectric focusing. 

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