ACE2-rich cells-targeted fluorescence imaging using newly discovered peptides from SARS-CoV-2 epitopes and neutralizing antibodies

The discovery of new targeting peptides for specific cells, tissues, or disease sites has gained significant attention in both basic research and translational medicine, particularly for the development of drug delivery platforms. This study identified a targeting peptide for ACE2-rich cells, which play a crucial role in maintaining blood–brain barrier integrity and neurovascular function, and applied the peptides for the fluorescence imaging of ACE2-rich cells. By analyzing the epitope sequences of the SARS-CoV-2 spike protein and the binding sites of neutralizing antibodies, we identified a hit peptide sequence, GFQPTNGVGYQ. In vitro and in vivo experiments demonstrated the peptide's selective binding to ACE2-rich cells and its accumulation in brain tumor tissue in a glioblastoma mouse model. These findings provide valuable insights into the development of peptide-based therapeutics and hold potential for treating brain-related neurovascular diseases.