title: Topo-optical reactions for the identification of O-acyl sugars in amyloid deposits.
abstract: The aldehyde bisulfite toluidine blue (ABT) reaction with former saponification (KOH-ABT) and periodic acid-borohydride reduction-saponification (PB-KOH-ABT) were applied to sections of human amyloid deposits in the respiratory tract. The saponification-induced increase in ABT-reactivity was confined to the presence of O-acyl sugars associated with the amyloid fibrils. The anisotropic and metachromatic effect in the ABT and KOH-ABT reaction was reduced in the corresponding PB-KOH-ABT reaction, a difference attributed to the removal of staining due to neutral carbohydrate residues. Since the periodic acid-borohydride reduction abolishes all pre-existing ABT-reactivity of neutral sugar vicinal diols, the isolated KOH-effect could be shown using the PB-KOH-ABT reaction. By application of this sequence, the problem identifying small quantities of O-acyl sugars was solved. It is suggested that the KOH-effect depends upon the removal of O-acyl substituents located on the polyhydroxy side chain (C7, C8, C9) of sialic acid residues. An advantage of such topo-optical reactions over biochemical techniques is the exact localization of O-acyl sugars in tissue sites. By means of the KOH-ABT and PB-KOH-ABT reactions we have demonstrated, for the first time, that O-acyl sugars occur within amyloid deposits.
authors.affiliation: Institute of Pathology, Clinic of Gynaecology and Obstetrics, University of Rostock, Südring 81, D-18059 Rostock, Germany.
authors.forename: Susann
authors.initials: S
authors.lastname: Richter
authors.forename: Josef
authors.initials: J
authors.lastname: Makovitzky
mesh_terms: D000682:Amyloid / Q000032:analysis / Q000737:chemistry*; D002241:Carbohydrates / Q000032:analysis* / Q000737:chemistry*; D006651:Histocytochemistry / Q000379:methods*; D006801:Humans; D008853:Microscopy; D019158:N-Acetylneuraminic Acid / Q000737:chemistry; D013194:Staining and Labeling / Q000379:methods*; D014048:Tolonium Chloride / Q000737:chemistry
chemical_list: D000682:Amyloid; D002241:Carbohydrates; D014048:Tolonium Chloride; D019158:N-Acetylneuraminic Acid