Stéphanie Yen-Nicolaÿ1, Céline Boursier1, Marlène Rio2, Dirk J Lefeber3, Antoine Pilon4,5, Nathalie Seta6, Arnaud Bruneel4,6. 1. Trans-Prot, Proteomic facility, Université Paris-Sud, Châtenay-Malabry, France. 2. Département de Génétique, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France. 3. Laboratory of Genetics, Endocrine and Metabolic Diseases, Radboud University Medical Centre, Nijmegen, The Netherlands. 4. EA4530, Dynamique des microtubules en physiopathologie, Faculté de Pharmacie, Université Paris-Sud, Châtenay-Malabry, France. 5. APHP, Unité d'Hormonologie et Immunoanalyse, Pôle de Biologie Médicale et Pathologie, Hôpitaux Universitaires Est Parisien, Paris, France. 6. AP-HP, Biochimie métabolique et cellulaire, hôpital Bichat, Paris, France.
Abstract
PURPOSE: The O-glycan abnormalities accompanying some congenital disorders of glycosylation, namely conserved oligomeric Golgi-congenital disorders of glycosylation (COG-CDGs) and ATP6V0A2-CDGs, are mainly detected using electrophoresis methods applied to circulating apolipoprotein C-III. The objective of this study was to evaluate the reliability of MALDI-TOF MS of apoC-III for the detection and characterization of CDG-associated O-glycan defects. EXPERIMENTAL DESIGN: plasmas from CDG-negative, COG-CDG, and ATP6V0A2-CDG patients were analyzed and results were compared to those obtained using 2DE followed by Western blot. RESULTS: MALDI-TOF of apoC-III allowed to detect various significant O-glycan abnormalities in CDG-patients with emphasis to COG-CDG. Furthermore, in CDG samples, comparison study between 2DE and MALDI-TOF showed a particular behavior of monosialylated apoC-III in the mass spectrometer that could be related to an abnormal O-glycan structure. CONCLUSIONS AND CLINICAL RELEVANCE: MALDI-TOF MS appears as a powerful technique for the analysis of apoC-III glycoforms for potential routine screening of COG- and ATP6V0A2-CDGs.
PURPOSE: The O-glycan abnormalities accompanying some congenital disorders of glycosylation, namely conserved oligomeric Golgi-congenital disorders of glycosylation (COG-CDGs) and ATP6V0A2-CDGs, are mainly detected using electrophoresis methods applied to circulating apolipoprotein C-III. The objective of this study was to evaluate the reliability of MALDI-TOF MS of apoC-III for the detection and characterization of CDG-associated O-glycan defects. EXPERIMENTAL DESIGN: plasmas from CDG-negative, COG-CDG, and ATP6V0A2-CDGpatients were analyzed and results were compared to those obtained using 2DE followed by Western blot. RESULTS: MALDI-TOF of apoC-III allowed to detect various significant O-glycan abnormalities in CDG-patients with emphasis to COG-CDG. Furthermore, in CDG samples, comparison study between 2DE and MALDI-TOF showed a particular behavior of monosialylated apoC-III in the mass spectrometer that could be related to an abnormal O-glycan structure. CONCLUSIONS AND CLINICAL RELEVANCE: MALDI-TOF MS appears as a powerful technique for the analysis of apoC-III glycoforms for potential routine screening of COG- and ATP6V0A2-CDGs.