查看文章

A novel approach to treat cancer more selectively is achieved by targeting drugs to cells via conjugating the drug or imaging agent to an antibody or ligand for a cell surface receptor that is over‐expressed by the target cell population. Previous work by us has suggested that enhanced specificity can be obtained by multivalency of binding moieties. In this study we investigated the binding specificity of a multivalent construct including three peptides segments (TWYKIAFQRNRK), which bind the α₆β₁‐integrin, linked by poly(ethylene glycol) spacers. The binding specificity of the constructs was calculated by quantifying their binding to target cells (glioma cells, SF 767) relative to non‐targeted cells (normal human astrocytes, NHA). Dodecapeptide constructs (monovalent) exhibit specificity equal to the ratio of receptor expression at all concentrations. However, trivalent constructs demonstrated a sharp increase in …