Antigene strategies

The approaches described above target RNA and most often induce its selective degradation. The so-called triplex or antigene strategy rests upon the binding of an oligopyrimidine or an oligopurine to a... 

Since the work of Zamecnik and Stephenson in 1978, showing that a synthetic 13-mer complementary to the 3 - and 5 -terminal sequences of the Rous Sarcoma Virus 35S was able to inhibit virus production in infected chick embryo fibroblast cells [77][78], numerous studies have been done to demonstrate that in vivo oligonucleotides can bind to their complementary sequences in mRNAs or DNA and subsequently act on the cellular machinery. The purpose of this section is to present briefly the potential interest of the platinated oligonucleotides in the context of the antisense and antigene strategies (for a comprehensive view of the antisense and antigene strategies, see [79-83] and references herein). 

Ferdous, A., Watanabe, H., Akaike, T., Maruyama, A. Comb-type copolymer stabilization of triplex DNA and possible application in antigene strategy. J. Pharm. Sci. 87, 1400-1405... 

In the antigene strategy, the oligonucleotide binds to double-helical DNA and forms a triple helix. It can block transcription of a targeted gene. This strategy will be further discussed below (3,4). 

By similar logic, protein affinity Hbraries have been constmcted to identify protein—protein combining sites, as in antibody—antigen interaction (19) and recombinant Hbraries have been made which produce a repertoire of antibodies in E. coli (20). In another case, a potential DNA-based therapeutic strategy has been studied (21). DNAs from a partially randomized Hbrary were selected to bind thrombin in vitro. Oligonucleotides, termed aptamers that bound thrombin shared a conserved sequence 14—17 nucleotides long. 

The remarkable selectivity that is inherent in the reaction of an antibody with the antigen or hapten against which it was raised is the basis for the extensive use of immunoassay for the rapid analysis of samples in clinical chemistry. Immunochemical reactions offer a means by which the applicability of potentiometric techniques can be broadened. A number of strategies for incorporating immunoassay into the methodology of potentiometry have been explored... 

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