Aptamers directed against the SARS-Cov2 S protein (SARS-Cov2-Aptamers)

This proposal aims at isolating nucleic acid aptamers (ssDNA, 2'-F-RNA, clickmers) directed against the SARS-Cov2 S protein, and capable of blocking the binding of the virus to the ACE2 receptor. We will use the prefusion-stabilized S ectodomain (AA 1-1208) of the SARS-Cov2 S protein, described in Wrapp et al (2020), for which we have the respective expression plasmids. We will perform parallel SELEX en-richments of chemically stabilized aptamer libraries using our in-house automated selection platform. Moreover, we will also carry out a click-SELEX to enrich for clickmers. Besides in vitro binding assays to quantify the interaction of SARS-Cov2 S with ACE2 in presence of the isolated aptamers we will collaborate with virologists who will test the performance of the aptamers in infection studies in cell culture, and in virus replication assays. Anti-Cov2 S aptamers will be converted into rapid test assays (ELONA, Lateral Flow Assay, dip-stick assays) and will be further developed as therapeutics, e.g., in preventive protection sprays.