TY - JOUR A1 - Tscheuschner, Georg A1 - Kaiser, Melanie N. A1 - Lisec, Jan A1 - Beslic, D. A1 - Muth, Thilo A1 - Krüger, M. A1 - Mages, H. W. A1 - Dorner, B. G. A1 - Knospe, J. A1 - Schenk, J. A. A1 - Sellrie, F. A1 - Weller, Michael G. T1 - MALDI-TOF-MS-Based Identification of Monoclonal Murine Anti-SARS-CoV-2 Antibodies within One Hour N2 - During the SARS-CoV-2 pandemic, many virus-binding monoclonal antibodies have been developed for clinical and diagnostic purposes. This underlines the importance of antibodies as universal bioanalytical reagents. However, little attention is given to the reproducibility crisis that scientific studies are still facing to date. In a recent study, not even half of all research antibodies mentioned in publications could be identified at all. This should spark more efforts in the search for practical solutions for the traceability of antibodies. For this purpose, we used 35 monoclonal antibodies against SARS-CoV-2 to demonstrate how sequence-independent antibody identification can be achieved by simple means applied to the protein. First, we examined the intact and light chain masses of the antibodies relative to the reference material NIST-mAb 8671. Already half of the antibodies could be identified based solely on these two parameters. In addition, we developed two complementary peptide mass fingerprinting methods with MALDI-TOF-MS that can be performed in 60 min and had a combined sequence coverage of over 80%. One method is based on the partial acidic hydrolysis of the protein by 5 mM of sulfuric acid at 99 degrees C. Furthermore, we established a fast way for a tryptic digest without an alkylation step. We were able to show that the distinction of clones is possible simply by a brief visual comparison of the mass spectra. In this work, two clones originating from the same immunization gave the same fingerprints. Later, a hybridoma sequencing confirmed the sequence identity of these sister clones. In order to automate the spectral comparison for larger libraries of antibodies, we developed the online software ABID 2.0. This open-source software determines the number of matching peptides in the fingerprint spectra. We propose that publications and other documents critically relying on monoclonal antibodies with unknown amino acid sequences should include at least one antibody fingerprint. By fingerprinting an antibody in question, its identity can be confirmed by comparison with a library spectrum at any time and context. KW - Reproducibility KW - Quality control KW - Traceability KW - Peptides KW - Peptide mass fingerprinting KW - Monoclonal antibody KW - Recombinant antibody KW - Identity KW - Antibody identification KW - Sequencing KW - Light chain KW - Mass spectrometry KW - Software KW - Open science KW - Library KW - COVID-19 KW - Corona virus KW - Sequence coverage KW - NIST-mAb 8671 KW - Reference material KW - RBD KW - Spike protein KW - Nucleocapsid KW - Cleavage KW - Tryptic digest KW - MALDI KW - DHAP KW - 2,5-dihydroxyacetophenone KW - Github KW - Zenodo KW - ABID PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-547347 DO - https://doi.org/10.3390/antib11020027 VL - 11 IS - 2 SP - 1 EP - 22 PB - MDPI CY - Basel AN - OPUS4-54734 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Bosc-Bierne, Gaby A1 - Weller, Michael G. T1 - Investigation of Impurities in Peptide Pools N2 - Peptide pools are important research tools in different biomedical fields. They consist of a complex mixture of defined peptides, which places high demands on the production and quality control of these products. Previously it was shown that the combination of UHPLC with high-resolution mass-spectrometry (HRMS) is a fast and powerful method to confirm the relative concentration and the structural identity of all peptides expected to be in the pool. In this work, the additional information contained in the UV chromatograms and mass spectra is used to search for impurities due to synthesis by-products, degradation during storage and transportation and to identify possible analytical artifacts. It was shown that most impurities are only present in trace amounts and can be considered uncritical for most applications. The most frequent and perhaps unexpected impurities were homo- and heterodimers caused by the free cysteines contained in these peptide pools. Furthermore, pyroglutamate and aspartimide formation, deamidation, methionine oxidation, and amino acid deletions could be found. This list is not intended to be comprehensive, but rather a brief guide to quickly identify impurities and, in the long term, to suggest possible changes in the composition of the peptide pools to avoid such impurities by design or by special precautions. N2 - Peptidpools sind wichtige Forschungswerkzeuge in verschiedenen biomedizinischen Bereichen. Sie bestehen aus einer komplexen Mischung definierter Peptide, was hohe Anforderungen an die Produktion und Qualitätskontrolle dieser Produkte stellt. Zuvor wurde gezeigt, dass die Kombination von UHPLC mit hochauflösender Massenspektrometrie (HRMS) eine schnelle und leistungsstarke Methode ist, um die relative Konzentration und die strukturelle Identität aller Peptide zu bestätigen, die im Pool erwartet werden. In dieser Arbeit werden die zusätzlichen Informationen in den UV-Chromatogrammen und Massenspektren genutzt, um nach Verunreinigungen durch Synthesenebenprodukte, Abbau während der Lagerung und des Transports zu suchen und mögliche analytische Artefakte zu identifizieren. Es wurde gezeigt, dass die meisten Verunreinigungen nur in Spuren vorhanden sind und für die meisten Anwendungen als unkritisch angesehen werden können. Die häufigsten und vielleicht unerwartetsten Verunreinigungen waren Homo- und Heterodimere, die durch die in diesen Peptidpools enthaltenen freien Cysteine verursacht wurden. Außerdem konnten Pyroglutamat- und Aspartimidbildung, Deamidierung, Methioninoxidation und Aminosäurendeletion festgestellt werden. Diese Liste erhebt keinen Anspruch auf Vollständigkeit, sondern soll vielmehr eine kurze Anleitung zur schnellen Identifizierung von Verunreinigungen und langfristig zur Anregung möglicher Änderungen in der Zusammensetzung der Peptidpools sein, um solche Verunreinigungen durch Design oder besondere Vorsichtsmaßnahmen zu vermeiden. KW - Peptides KW - Mixtures KW - Degradation KW - Rearrangement KW - Cystein-Dimers KW - Immunology KW - MHC PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-621270 DO - https://doi.org/10.20944/preprints202412.0832.v1 SP - 1 EP - 16 PB - MDPI CY - Basle, Switzerland AN - OPUS4-62127 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -