Escort aptamers: a delivery service for diagnosis and therapy

Abstract

In 1990, the discovery of aptamers by Tuerk and Gold(1) and subsequently by Ellington and Szostak (2)spawned significant interest within academia andindustry. Aptamers have quickly become valuableresearch tools (3–5). More than that, a therapeuticaptamer (6) has entered clinical evaluation just eightyears after the inception of the technology. Whileaptamers have built inroads into therapeutic applica-tions, they may also become important in vitro diag-nostic tools (7). Here, we discuss a new development:the use of “escort aptamers” as targeting agents for invivo diagnosis and therapy. Instead of directly inter-rupting a disease process, as would a function-blockingaptamer, escort aptamers are designed to deliverradionuclides, toxins, or cytotoxic agents to diseasedtissue. Specifically, we focus on the delivery of benignradionuclides for in vivo diagnosis of disease. For dis-cussion of function-blocking aptamers, see White et al.,this Perspective series (8).