Szardenings, MichaelMichaelSzardeningsDelaroque, NicolasNicolasDelaroqueKern, KarolinKarolinKernRamirez-Caballero, LisbethLisbethRamirez-CaballeroPuder, MarcusMarcusPuderEhrentreich-Förster, EvaEvaEhrentreich-FörsterBeige, JoachimJoachimBeigeZürner, SebastianSebastianZürnerPopp, GeorgGeorgPoppWolf, JohannesJohannesWolfBorte, StephanStephanBorte2023-08-282023-08-282023https://publica.fraunhofer.de/handle/publica/44880710.3390/vaccines110914032-s2.0-85172279605Background: Coronavirus proteins are quite conserved amongst endemic strains (eCoV) and SARS-CoV-2. We aimed to evaluate whether peptide epitopes might serve as useful diagnostic biomarkers to stratify previous infections and COVID-19. Methods: Peptide epitopes were identified at an amino acid resolution that applied a novel statistical approach to generate data sets of potential antibody binding peptides. Results: Data sets from more than 120 COVID-19 or eCoV-infected patients, as well as vaccinated persons, have been used to generate data sets that have been used to search in silico for potential epitopes in proteins of SARS-CoV-2 and eCoV. Peptide epitopes were validated with >300 serum samples in synthetic peptide micro arrays and epitopes specific for different viruses, in addition to the identified cross reactive epitopes. Conclusions: Most patients develop antibodies against non-structural proteins, which are useful general markers for recent infections. However, there are differences in the epitope patterns of COVID-19, and eCoV, and the S-protein vaccine, which can only be explained by a high degree of cross-reactivity between the viruses, a pre-existing immune response against some epitopes, and even an alternate processing of the vaccine proteins.enCoronavirusCOVID-19EpitopesCross-reactivitySerologyPeptide arrayArray image processingBiomarkersjournal article