Exploratory Study on Autoantibodies to Arginine-rich Human Peptides Mimicking Epstein-Barr Virus in Women with Post-COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Friederike Hoheisel^1*Kathrin Maria Fleischer^2,3*Kerstin Rubarth⁴Nuno Sepúlveda^5,6Sandra Maria Bauer¹Frank Konietschke⁴Claudia Kedor¹Annika Elisa Stein¹Kirsten Wittke¹Martina Seifert^1,7,8Judith Theresia Bellmann-Strobl^10,9Josef Mautner^11,12,2Uta Behrends^11,12,3Carmen Scheibenbogen¹Franziska Sotzny^1*

• ¹Charite - Universitatsmedizin Berlin Institut fur Medizinische Immunologie, Berlin, Germany
• ²Helmholtz Zentrum Munchen Institut fur Virologie, Munich, Germany
• ³Technische Universitat Munchen School of Medicine and Health, Munich, Germany
• ⁴Charite - Universitatsmedizin Berlin Institut fur Biometrie und Klinische Epidemiologie, Berlin, Germany
• ⁵Politechnika Warszawska Wydzial Matematyki i Nauk Informacyjnych, Warsaw, Poland
• ⁶CEAUL - Centro de Estatística e Aplicações, Universidade de Lisboa, Lisbon, Portugal
• ⁷Berlin Institute of Health at Charite Center for Regenerative Therapies, Berlin, Germany
• ⁸Deutsches Zentrum fur Herz-Kreislauf-Forschung eV, Berlin, Germany
• ⁹Experimental and Research Center (ECRC), Charite - Universitatsmedizin Berlin, Berlin, Germany
• ¹⁰Charite - Universitatsmedizin Berlin Exzellenzcluster NeuroCure, Berlin, Germany
• ¹¹Deutsches Zentrum für Infektionsforschung, Berlin, Germany
• ¹²Technische Universitat Munchen, Munich, Germany

Abstract Introduction: Epstein-Barr virus (EBV) infection is a well-established trigger and risk factor for both myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and post-COVID syndrome (PCS). In previous studies, we identified elevated IgG responses to arginine-rich (poly-R) sequences within the EBV nuclear antigens EBNA4 and EBNA6 in post-infectious ME/CFS (piME/CFS). Building on these findings, this exploratory study examines IgG reactivity to poly-R-containing EBV-derived peptides and homologous human peptides in women with PCS and ME/CFS. Methods: IgG reactivity to poly-R containing peptides derived from EBNA4 and EBNA6, and homologous human 15-mer peptides and the corresponding full-length proteins, was assessed using a cytometric bead array (CBA) and a multiplex dot-blot assay. Serum samples were analyzed from 45 female PCS patients diagnosed according to WHO criteria, including 26 who also met the Canadian Consensus criteria for ME/CFS (pcME/CFS), 36 female patients with non-COVID post-infectious ME/CFS (piME/CFS), and 34 female healthy controls (HC). Results: Autoantibodies targeting poly-R peptide sequences of the neuronal antigen SRRM3, the ion channel SLC24A3, TGF-β signaling regulator TSPLY2, and the angiogenesis-related protein TSPYL5, as well as full-length α-adrenergic receptor (ADRA) proteins, were more frequently detected in patient groups. Several of these autoantibodies showed positive correlations with core symptoms, including autonomic dysfunction, fatigue, cognitive impairment, and pain. Conclusion: This exploratory study identify autoantibodies directed against EBV mimicking arginine-rich sequences in human proteins, suggesting a potential role for molecular mimicry in the pathogenesis of PCS and ME/CFS.