{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T05:06:08Z","timestamp":1780635968379,"version":"3.54.1"},"reference-count":15,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,5,29]],"date-time":"2026-05-29T00:00:00Z","timestamp":1780012800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibodies"],"abstract":"<jats:p>Background\/Objectives: Ocrelizumab is a humanized monoclonal antibody targeting CD20, approved for the treatment of adult patients with relapsing multiple sclerosis (RMS) and primary progressive multiple sclerosis (PPMS). The neutralizing activity of anti-drug antibodies (ADAs), especially neutralizing ADAs (nADAs) activity, should be examined considering that it can alter pharmacokinetic (PK) and pharmacodynamic (PD) profiles, reduce drug efficacy, and lead to life-threatening adverse events. Methods: This article presents data on the development and validation of an assay for neutralizing anti-drug antibodies (nADA) based on ADCC reporter cells for the analysis of patient sera in the context of ocrelizumab clinical studies. Results: Critical steps and conditions to minimize assay variability were identified. The lower limit of detection was 549.6 ng\/mL. The cutoff for nonspecific neutralization was determined as 19.7%. The presence of 0.37\u20133.0 \u03bcg\/mL ocrelizumab in a biological sample enables the detection of 1.1\u201310.0 \u03bcg\/mL polyclonal anti-ocrelizumab idiotype antibodies, respectively. Conclusions: The developed method can be used for immunogenicity studies of medicinal products containing ocrelizumab.<\/jats:p>","DOI":"10.3390\/antib15030046","type":"journal-article","created":{"date-parts":[[2026,5,29]],"date-time":"2026-05-29T17:36:18Z","timestamp":1780076178000},"page":"46","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Development and Validation of Cell-Based Bioassay for the Detection of Neutralizing Antibodies to Ocrelizumab in Human Serum Using Antibody-Dependent Cell-Mediated Cytotoxicity Test in a Reporter Cell Line Expressing Fc\u03b3RIIIa"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0023-0028","authenticated-orcid":false,"given":"Olga","family":"Strizhakova","sequence":"first","affiliation":[{"name":"JSC \u201cGENERIUM\u201d, 14, Vladimirskaya Street, Volginskiy 601125, Vladimir Region, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Grigory","family":"Poroshin","sequence":"additional","affiliation":[{"name":"JSC \u201cGENERIUM\u201d, 14, Vladimirskaya Street, Volginskiy 601125, Vladimir Region, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5099-3050","authenticated-orcid":false,"given":"Andrei","family":"Pershin","sequence":"additional","affiliation":[{"name":"JSC \u201cGENERIUM\u201d, 14, Vladimirskaya Street, Volginskiy 601125, Vladimir Region, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yana","family":"Bakhareva","sequence":"additional","affiliation":[{"name":"JSC \u201cGENERIUM\u201d, 14, Vladimirskaya Street, Volginskiy 601125, Vladimir Region, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ivan","family":"Shevchenko","sequence":"additional","affiliation":[{"name":"JSC \u201cGENERIUM\u201d, 14, Vladimirskaya Street, Volginskiy 601125, Vladimir Region, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9058-1106","authenticated-orcid":false,"given":"Ivan","family":"Lyagoskin","sequence":"additional","affiliation":[{"name":"JSC \u201cGENERIUM\u201d, 14, Vladimirskaya Street, Volginskiy 601125, Vladimir Region, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6532-7835","authenticated-orcid":false,"given":"Rakhim","family":"Shukurov","sequence":"additional","affiliation":[{"name":"JSC \u201cGENERIUM\u201d, 14, Vladimirskaya Street, Volginskiy 601125, Vladimir Region, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1314-894X","authenticated-orcid":false,"given":"Ravil","family":"Khamitov","sequence":"additional","affiliation":[{"name":"JSC \u201cGENERIUM\u201d, 14, Vladimirskaya Street, Volginskiy 601125, Vladimir Region, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,29]]},"reference":[{"key":"ref_1","unstructured":"FDA\/CDER\/CBER (2019). 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Disord."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1417","DOI":"10.1208\/s12248-015-9798-5","article-title":"A Neutralizing Antibody Assay Based on a Reporter of Antibody-Dependent Cell-Mediated Cytotoxicity","volume":"17","author":"Wu","year":"2015","journal-title":"AAPS J."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"97","DOI":"10.1208\/s12248-023-00858-7","article-title":"An Antibody-Dependent Cellular Cytotoxicity Assay for Detecting Ocrelizumab Neutralizing Antibody","volume":"25","author":"Nguyen","year":"2023","journal-title":"AAPS J."}],"container-title":["Antibodies"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4468\/15\/3\/46\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T04:48:27Z","timestamp":1780634907000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4468\/15\/3\/46"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,5,29]]},"references-count":15,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["antib15030046"],"URL":"https:\/\/doi.org\/10.3390\/antib15030046","relation":{},"ISSN":["2073-4468"],"issn-type":[{"value":"2073-4468","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,29]]}}}