TY - JOUR U1 - Zeitschriftenartikel, wissenschaftlich - begutachtet (reviewed) A1 - Danquah, Bright D. A1 - Röwer, Claudia A1 - Opuni, Kwabena F. M. A1 - El-Kased, Reham A1 - Frommholz, David A1 - Illges, Harald A1 - Koy, Cornelia A1 - Glocker, Michael O. T1 - Intact Transition Epitope Mapping - Targeted High-Energy Rupture of Extracted Epitopes (ITEM-THREE) JF - Molecular & Cellular Proteomics N2 - Epitope mapping, which is the identification of antigenic determinants, is essential for the design of novel antibody-based therapeutics and diagnostic tools. ITEM-THREE is a mass spectrometry-based epitope mapping method that can identify epitopes on antigens upon generating an immune complex in electrospray-compatible solutions by adding an antibody of interest to a mixture of peptides from which at least one holds the antibody's epitope. This mixture is nano-electrosprayed without purification. Identification of the epitope peptide is performed within a mass spectrometer that provides an ion mobility cell sandwiched in-between two collision cells and where this ion manipulation setup is flanked by a quadrupole mass analyzer on one side and a time-of-flight mass analyzer on the other side. In a stepwise fashion, immune-complex ions are separated from unbound peptide ions and dissociated to release epitope peptide ions. Immune complex-released peptide ions are separated from antibody ions and fragmented by collision induced dissociation. Epitope-containing peptide fragment ions are recorded, and mass lists are submitted to unsupervised data base search thereby retrieving both, the amino acid sequence of the epitope peptide and the originating antigen. ITEM-THREE was developed with antiTRIM21 and antiRA33 antibodies for which the epitopes were known, subjecting them to mixtures of synthetic peptides of which one contained the respective epitope. ITEM-THREE was then successfully tested with an enzymatic digest of His-tagged recombinant human β-actin and an antiHis-tag antibody, as well as with an enzymatic digest of recombinant human TNFα and an antiTNFα antibody whose epitope was previously unknown. KW - Protein complex analysis KW - Non-covalent interaction MS* KW - Assay development KW - epitope mapping KW - Immunology* KW - data base search KW - Targeted mass spectrometry KW - Antibodies* KW - peptide sequencing KW - Ligand -Receptor Interactions* KW - Therapeutic antibodies* KW - BLAST KW - Mass spectrometry KW - Affinity proteomics UN - https://nbn-resolving.org/urn:nbn:de:hbz:1044-opus-45635 SN - 1535-9476 SS - 1535-9476 U6 - https://doi.org/10.1074/mcp.RA119.001429 DO - https://doi.org/10.1074/mcp.RA119.001429 PM - 31147491 VL - 18 IS - 8 SP - 1543 EP - 1555 PB - American Society for Biochemistry and Molecular Biology ER -