MSACL 2024 Abstract

UPLC-MS/MS Analysis of Urinary Oligosaccharides and Glycoamino Acids for the Diagnosis of Mucopolysaccharidosis and Glycoproteinosis

Xinying Hong (1, 2), Parith Wongkittichote (1, 3), Stephanie Cho (1), Artis Miller (1), Kaitlyn King (1), Zackary M. Herbst (4), Zhimei Ren (5), Michael H. Gelb (4, 6)
(1) Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA (2) Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA (3) Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand (4) Department of Chemistry, University of Washington, Seattle, WA, USA (5) Department of Statistics and Data Science, The Wharton School of the University of Pennsylvania, Philadelphia, Pennsylvania, USA (6) Department of Biochemistry, University of Washington, Seattle, WA, USA

Xinying Hong, PhD (Presenter) The Children’s Hospital of Philadelphia

Presenter Bio: Dr. Xinying Hong is a board-certified clinical biochemical geneticist and Assistant Professor of Pathology and Laboratory Medicine at the Children's Hospital of Philadelphia, where she also serves as Assistant Director of the Metabolic and Advanced Diagnostic Laboratory. She earned her PhD in Chemistry from the University of Washington and completed her clinical training at CHOP. Dr. Hong’s research focuses on the discovery and clinical application of novel biomarkers to improve the diagnosis, prognosis, and treatment monitoring of inborn errors of metabolism, with a particular emphasis on lysosomal storage disorders.

Relevant Financial Disclosures (within past 24 months, reported on May 31, 2026) No relevant financial relationship(s) to disclose. Discussing Products? NO, presenter will NOT present educational content related to products/services of the ineligible company(ies) listed above. Conflict mitigation NOT REQUIRED.

Background: Mucopolysaccharidosis (MPS) and glycoproteinosis are two groups of heterogenous lysosomal storage disorders (LSDs) caused by defective degradation of glycosaminoglycans (GAGs) and glycoprotein, respectively. Oligosaccharides and glycoamino acids have been recognized as biomarkers for MPS and glycoproteinosis. Given both groups of diseases have overlapping clinical features, a multiplexed assay capable of unambiguous subtyping is desired for accurate diagnosis, and potentially for severity stratification and treatment monitoring.

Methods: Urinary oligosaccharides were derivatized with 3-methyl-1-phenyl-2-pyrazoline-5-one (PMP) and analyzed by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) together with the underivatized glycoamino acids. Novel biomarkers were identified with a semi-targeted approach with precursor mass, the fragmentation pattern (if applicable), and the biochemical basis of the condition.

Results: A UPLC-MS/MS analysis with improved chromatographic separation was developed. Novel biomarkers for MPS-IIIA, IIIB, IIIC, and VII were identified and validated. A total of 28 oligosaccharides, 2 glycoamino acids, and 2 ratios were selected as key diagnostic biomarkers. Validation studies including linearity, LLOQ and precision were carried out with the assay performance meeting the criteria. Age-specific reference ranges were collected. In the 76 untreated patients, unambiguous diagnosis was achieved with 100% sensitivity and specificity. Additionally, the levels of disease-specific biomarkers were substantially reduced in the treated patients.

Conclusions: A multiplexed UPLC-MS/MS assay for urinary oligosaccharides and glycoamino acids measurement was developed and validated. The assay is suitable for the accurate diagnosis and subtyping MPS and glycoproteinosis and potentially for severity stratification and monitoring response to treatment.