Trophoblast-Specific β₁-Glycoprotein: Its Spatial Structure and Localization of Antigenic Determinants

Abstract

Effects of temperature and pH on the spatial structures of trophoblast-specific β₁ -glycoprotein (TSG) and its various derivatives and fragments have been studied by circular dichroic spectroscopy. The spatial organization of the protein portion of TSG derivatives, as revealed by the spectroscopic evidence, has been discussed with respect to the antigenic activity of the species studied. We concluded that the TSG protein portion consists mainly of a β-structural type. The antigenic determinants were shown to be topographic, and are preferentially localized in the protein portion; only about 15 % of the TSG antigenic activity failed to bear a direct relation to the spatial structure. The antigenic determinants seemed to include a tryptophan residue.

A Novel Bifunctional Hybrid with Marine Bacterium Alkaline Phosphatase and Far Eastern Holothurian Mannan-Binding Lectin Activities

“…Although the holothurian MBL- AJ and mammalian lectins, including human MBL, had common properties to recognize bacterial mannans, the differences in the carbohydrate-binding specificities were found to be significant [5] . It has been previously shown that holothurian lectin MBL- AJ interacts with the promising cancer biomarkers in the following order of the lectin-binding affinity: CEA, embryonic α-1-acid glycoprotein, trophoblast-specific β1-glycoprotein and α-fetoprotein isolated from the abortive and retroplacental blood [13] , [30] , [31] , [32] . MBL- AJ is not inhibited by monosaccharide, which is in the content of the normal human glycoconjugate's carbohydrate chains, and does not interact with the human blood serum components.…”

Carcinoembryonic Antigen, Its Spatial Structure and Localization of Antigenic Determinants

“…Immunochemical analysis and SDS electrophore sis were carried out as described earlier [6,7], CD and CR spectra were recorded and analyzed as described earlier [7,8], Differential UV spectra of thermal per turbation were performed as reported earlier [7,9]. Polyclonal rabbit antisera were used in all the immu nochemical assays.…”

“…Polyclonal rabbit antisera were used in all the immu nochemical assays. Antigenic activity was determined by the usual immune enzyme 'sandwich' assay as described earlier [7,10], using a borate buffer [11].…”