New approaches for cell-specific targeting: identification of cell-selective peptides from combinatorial libraries

Peptides that recognize specific cell types promise to be valuable tools bo th in research and clinical applications. Cell-specific peptides can be use ful as drug delivery vehicles, diagnostic agents, affinity reagents for cel l purification, gene therapy delivery agents, and research tools to probe t he nature of a cell's surface. Recently, cell-specific targeting-peptides h ave been identified by phage-display selections against purified cell-surfa ce markers, whole cells in tissue culture, and even tissues within live ani mals. These methods for identifying cell-targeting peptides will certainly increase the tools available to the scientist for cell-specific targeting.