Autoantibodies mimicking EBV sequences in ME/CFS and PCS

Dr Franziska Sotzny discussed the role of G protein-coupled receptor (GPCR) antibodies in ME/CFS and Long COVID. She focused on the molecular mimicry of the Epstein-Barr virus (EBV) and SARS-CoV-2, which describes similar molecular properties of the virus with the body's own structures. Since SARS-CoV-2 infections can lead to EBV reactivation, this mimicry also increases the likelihood that human antigens will mistakenly become the target of antibodies during the immune response. This can increase the likelihood of autoimmune reactions after the acute phase of infection. In studies, IgG immunoglobulins (a specific class of antibodies) bound to human arginine-rich peptide sequences that are very similar to the binding sites on EBV or SARS-CoV-2. Examples of potential arginine-rich epitopes include the α-adrenergic receptor, mitochondrial and neuronal antigens, ion channels, or regulatory or proangiogenic epitopes. Furthermore, positive correlations between antibody concentrations and specific ME/CFS symptoms (e. g. cognitive impairment, muscle pain, headache, autonomic dysfunction, fatigue, and Post-exertional Malaise (PEM)) were identified in patient subgroups.