(T1530-02-06) Development of an Electrochemiluminescent Assay for the Detection of Anti-PEG IgE Antibodies in Human Serum

Purpose: The incorporation of PEG in pharmaceuticals has been a common strategy to improve drug properties, but it has also led to the induction of anti-PEG antibodies in some individuals. Among these, anti-PEG IgE antibodies are of particular concern due to their potential role in hypersensitivity reactions¹. The detection and accurate quantification of these antibodies are critical for assessing the risk of allergic reactions. However, the measurement is complicated by several factors, including the low concentration of anti-PEG IgE in serum and the presence of other anti-PEG antibody isotypes that can interfere with detection.

Methods: To overcome the challenges associated with measuring anti-PEG IgE, we have developed an electrochemiluminescent (ECL) assay that provides enhanced sensitivity and specificity. The assay employs a bead-based enrichment strategy to selectively isolate anti-PEG IgE antibodies, effectively reducing interference from other isotypes. After enrichment, the samples are transferred to an MSD plate coated with PEGylated protein, which captures the anti-PEG IgE antibodies. Detection is achieved using a Ruthenylated anti-IgE antibody, enabling the ECL signal.

Results: The ECL assay developed for the detection of anti-PEG IgE antibodies demonstrates a high level of sensitivity, with the ability to detect concentrations as low as 50 ng/mL. Furthermore, the assay is robust against interference from other anti-PEG immunoglobulins, maintaining accuracy even when these are present at more than 100-fold molar excess. This level of sensitivity and specificity represents a significant advancement in the field, providing a reliable tool for monitoring anti-PEG IgE levels in patients.

Conclusion: The newly developed ECL assay represents a significant advancement in the detection of anti-PEG IgE antibodies. This assay can be integrated into most laboratories performing plate-based ligand binding assays, whereas other methods in the literature require use of a flow cytometer and highly trained staff to operate the instrument². The assay is sensitive and specific for anti-PEG IgE antibodies and will be validated as per the regulatory standards for the support of clinical studies.

References: 1. Stone CA Jr, Liu Y, Relling MV, Krantz MS, Pratt AL, Abreo A, Hemler JA, Phillips EJ. Immediate Hypersensitivity to Polyethylene Glycols and Polysorbates: More Common Than We Have Recognized. J Allergy Clin Immunol Pract. 2019 May-Jun;7(5):1533-1540.
2. Zhou ZH, Stone CA Jr, Jakubovic B, Phillips EJ, Sussman G, Park J, Hoang U, Kirshner SL, Levin R, Kozlowski S. Anti-PEG IgE in anaphylaxis associated with polyethylene glycol. J Allergy Clin Immunol Pract. 2021 Apr;9(4):1731-1733.

Anti-PEG IgE Sensitivity Curve

Effect of Anti-PEG Immunoglobulins on Anti-PEG IgE Detection