title: Comparison of N-linked glycosylation of protein C in newborns and adults.
abstract: Protein C (PC) is a major anticoagulant that stems the propagation of thrombin. The activated form of PC (APC), in association with the cofactor protein S, proteolytically converts activated coagulation factors VIIIa and Va into inactive forms. Studies have shown that forms of PC that contain 3N-linked glycans (beta-PC) are functionally distinct from the fully glycosylated 4-glycan type (alpha-PC). Since some findings have also hinted at qualitative differences in PC from newborns and adults, we decided to determine the relative constitution of glycoforms in these age groups. Subtypes of PC in newborn and adult plasmas were distinguished by SDS polyacrylamide electrophoresis and Western blotting, followed by immunological analysis. Newborns were found to have alpha-PC/beta-PC mole ratios of 8.8:1, compared to 2.3:1 in adults. PC was also isolated by immunoaffinity chromatography from newborn and adult plasmas. Glycans were released by protease treatment and studied by mass spectrometry. Results from glycan analysis showed a small range of glycan structures in both age groups. No clear differences were noted between newborn and adult PC microheterogeneity in glycan structures (branching). We conclude that newborns have important differences in PC macroheterogeneity in glycoform content relative to adults. This age-dependent glycosylation variation may have implications in management of PC function in vivo.
authors.affiliation: McMaster University, Thrombosis and Atherosclerosis Research Institute (TaARI), C4-121, David Braley Cardiac, Vascular and Stroke Research Institute, 237 Barton St. E., Hamilton, Ontario, Canada L8L 2X2.
authors.forename: Leslie R
authors.initials: LR
authors.lastname: Berry
authors.forename: Maria C
authors.initials: MC
authors.lastname: Van Walderveen
authors.forename: Helen M
authors.initials: HM
authors.lastname: Atkinson
authors.forename: Anthony K C
authors.initials: AK
authors.lastname: Chan
mesh_terms: D000328:Adult; D004591:Electrophoresis, Polyacrylamide Gel; D006026:Glycoside Hydrolases / Q000737:chemistry; D006031:Glycosylation; D006801:Humans; D007118:Immunoassay / Q000379:methods; D007231:Infant, Newborn; D013058:Mass Spectrometry; D008875:Middle Aged; D010455:Peptides / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry*; D011486:Protein C / Q000737:chemistry*; D017293:Protein S / Q000737:chemistry; D014470:Umbilical Cord / Q000737:chemistry; D055815:Young Adult
chemical_list: D010455:Peptides; D011134:Polysaccharides; D011486:Protein C; D017293:Protein S; D006026:Glycoside Hydrolases