Characterization of the Human Serum Antibody Profile of Long-COVID Patients Using the DNA Aptamer BC007

DNA aptamers are a class of substances with many biological applications as biosensors, pharmaceuticals and in bioimaging. Aptamers developed against certain biomolecules bind them, e.g., in physiological fluids, as selectively as possible. Other aptamers, which are less selective, are suitable for obtaining a qualitative and quantitative insight into an entire proteome and thus for detecting and partially identifying dozens, even hundreds, of proteins. In this way, differences in the profile of the bound proteins can be determined in human sera from healthy donors and patients. With our investigations, we aim to determine autoantibody changes in the course of the disease of Long-COVID patients. We are convinced that certain patterns can be seen in the type and amount of antibodies in the serum of Long-COVID patients. We use the GPCR antibody-binding aptamer BC007, of which binding to the corona spike protein and the RNA-dependent RNA protease was also demonstrated, as DNA aptamer for our investigations. In our joint project, this aptamer is used both for the enrichment and analysis of GPCR autoantibodies, which are probably responsible for Long-COVID, and for the therapy of Long-COVID by neutralizing GPCR autoantibodies.