A peptide release system using a photo-cleavable linker in a cell array format for cell-toxicity analysis

Abstract

We constructed a novel peptide-array format system for cellular toxicity analysis. In this system, a peptide was immobilized on a conventional 96-well plate bottom via a photo-cleavable linker. Once UV light irradiated the desired wells, the peptide was released from the bottom. As a result, the cytotoxic behavior of the peptide could be monitored. Immobilization and light-irradiation conditions were optimized. The immobilized peptide showed no cytotoxicity; therefore, the cells could be cultured on the peptide-immobilizing plate from the beginning of the experiment. Cell-toxicity assays with this system for three cell types were performed. All cell types showed ∼25% lowering of viability with the photo-released 5-(and-6)-carboxytetramethylrhodamine (TMR)-GKLAKLAKKLAKLAKKLAKLAKGC (TMR-KLA-C) peptide compared with the non-coated plate. This relative toxicity nearly corresponded to that of ∼10 μM TMR-KLA-C in solution, and we found that the released peptide concentration per well was ∼10 μM at 60 min irradiation. Throughout this study, we successfully immobilized peptides via the photo-cleavable linker, released them by UV irradiation spatiotemporally and conducted the cell-toxicity assay. This study implies that the peptide photo-releasing array system will allow the realization of high-throughput cell arrays for cellomics analyses and cell-based phenotypic drug screenings. A novel peptide-array format system with a photo-cleavage linker for cellular toxicity analysis was constructed. In this system, a peptide was immobilized on a commercially available plate bottom via the photo-cleavable linker. UV light irradiation on the desired wells releases the peptide from the plate bottom, and then the cytotoxic behavior of the peptide can be monitored.