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Updated: Apr 28, 2026
In Vitro Enzyme Measurement to Test Pharmacological Chaperone Responsiveness in Fabry and Pompe Disease
Published on: December 20, 2017
Sex-based antibody subclass maturation drives direct enzymatic inhibition in fabry disease patients receiving enzyme
Tomas Baldwin1, Hibba Kurdi2, Ivan Doykov1
1Genetics and Genomic Medicine Department, UCL Institute of Child Health, London, United Kingdom.
Background:
Enzyme replacement therapy (ERT) for Fabry disease can elicit anti-drug antibodies (ADAs) that may diminish efficacy and limit clinical benefit.
Objectives:
To develop and apply a multiplexed proteomic assay for quantitative, subclass-specific ADA and complement profiling in Fabry disease to inform personalized ERT selection.
Methods:
We created a targeted LC-MS/MS platform to quantify ADA binding across IgG1-4, IgM, and IgA1, and complement proteins C1Qc-C9, in serum from Fabry patients (n = 39) and healthy controls. Neutralizing capacity was measured via enzymatic inhibition assay. Subclass-specific cross-reactivity was assessed for agalsidase alfa, agalsidase beta, and pegunigalsidase alfa.
Results:
IgG4 binding was significantly higher in Fabry males (p = 0.007), with no sex-based differences for other Ig classes. Complement binding (C1Qc, C3) was elevated in ∼25% of patients, with IgG1, IgG2, IgM, and IgA1 correlating with C1Qc (r > 0.6). Seven patients (three female) exhibited >50% ERT inhibition; IgG4 binding correlated with enzymatic inhibition (p < 0.0025) and elevated lyso-Gb3 in males (p < 0.02). We assessed cross-reactivity of IgG4 in a patient who had received only agalsidase alfa, finding a 49% reduction in IgG4 binding to Pegunigalsidase alfa compared to Agalsidase alfa (p = 0.003) and 45% to Peguingalsidase alfa compared to agalsidase beta (p = 0.035). IgG4 comprised >50% of immune complexes for agalsidase alfa/beta but only 25% for pegunigalsidase alfa, indicating a potentially distinct immunogenic profile.
Conclusion:
Quantitative subclass-specific ADA and complement profiling reveals sex-specific IgG4 patterns, neutralizing capacity, and ERT-specific immunogenic differences, supporting its utility for personalized therapy in Fabry disease.
Capsule Summary:
A novel multiplex LC-MS/MS assay quantifies ADA subclasses and complement in Fabry disease, uncovering distinct IgG4 patterns and ERT-specific profiles that enhance understanding of treatment immunogenicity.
