Generation of Species Cross-reactive Aptamers Using “Toggle” SELEX

• Published in: Molecular therapy Vol. 4; no. 6; pp. 567 - 573
• Main Authors: White, Rebekah, Rusconi, Christopher, Scardino, Elizabeth, Wolberg, Alisa, Lawson, Jeffrey, Hoffman, Maureane, Sullenger, Bruce
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-12-2001; Elsevier Limited
• Subjects: Animals; anticoagulation; aptamer; Base Sequence; Binding Sites; Blood Coagulation - drug effects; Cloning, Molecular; combinatorial chemistry; Combinatorial Chemistry Techniques; Cross Reactions; drug development; Gene Library; Gene therapy; HIV; Human immunodeficiency virus; Humans; Hyperplasia; Kinases; Ligands; Molecular Sequence Data; Nucleic Acid Conformation; Oligodeoxyribonucleotides - chemical synthesis; Peptide Library; Proteins; RNA - chemical synthesis; RNA - pharmacology; species cross-reactivity; Species Specificity; Swine; thrombin; Thrombin - antagonists & inhibitors; Thrombin - genetics; Thrombin Time; drug development; species cross-reactivity; thrombin; combinatorial chemistry; aptamer; anticoagulation
• ISSN: 1525-0016; 1525-0024
• DOI: 10.1006/mthe.2001.0495

Species cross-reactivity facilitates the preclinical evaluation of potentially therapeutic molecules in animal models. Here we describe an in vitro selection strategy in which RNA ligands (aptamers) that bind both human and porcine thrombin were selected by “toggling” the protein target between human and porcine thrombin during alternating rounds of selection. The “toggle” selection process yielded a family of aptamers, all of which bound both human and porcine thrombin with high affinity. Toggle-25, a characteristic member, inhibited two of thrombin's most important functions: plasma clot formation and platelet activation. If appropriate targets are available, the toggle strategy is a simple measure that promotes cross-reactivity and may be generalizable to related proteins of the same species as well as to other combinatorial library screening strategies. This strategy should facilitate the isolation of ligands with needed properties for gene therapy and other therapeutic and diagnostic applications.