| 摘要 |
<p>A system for localizing a diagnostic or therapeutic agent to an internal target site. The system includes (1) a biotinylated compound, (2) an avidin-containing binding protein capable of localizing selectively at the target tissue, when administered parenterally, and (3) a clearing agent which can bind to and cross-link the binding protein, to form a protein aggregate which is readily cleared from the subject's bloodstream. In practicing the method of the invention, the binding protein is administered to the subject parenterally, and allowed to localize at the target site, typically within 1-4 days. This is followed by a chase with the clearing agent to remove circulating, but not target-localized binding protein. When the biotinylated compound is administered, binding of the compound to the localized binding protein, and rapid clearance of unbound compound by the kidneys, results in selective localization of the compound at the target site.</p> |
