Oligosaccharides released by hydrazinolysis from Tamm-Horsfall protein of various human donors contain similar high-mannose glycans

As pathophysiological functions claimed for Tamm-Horsfall protein (THP) are related to its sugar moiety, we examined influence of pregnancy and variou s diseases on high-mannose chains. Hydrazinolysis was used to liberate olig osaccharides from THP polypeptide backbone. After HPLC separation of fluore scently labelled glycans similar profiles of neutral oligosaccharides were observed in THP of healthy subjects, pregnant women, patients with Bartter' s syndrome, patients with acute lymphoblastic leukemia and a patient with c arbohydrate deficient glycoprotein syndrome. THP contains Man-5, Man-6 and Man-7 glycans, with the preponderant amount of Man-6 glycan (about 7% of to tal THP oligosaccharides). No statistically significant differences were fo und in THP high-mannose glycans profiles between control subjects and pregn ant women or patients. It is likely that neither pregnancy nor the patholog ical conditions examined affect high-mannose chains. In our opinion hydrazi nolysis as a method of oligosaccharides liberation, in contrast to enzymati c deglycosylation, is more appropriate for analysis of the sugar moiety of THP. (C) 1999 Elsevier Science B.V. All rights reserved.