Aptamers as therapeutic and diagnostic agents.

Aptamers are oligonucleotides derived from an in vitro evolution process called SELEX. Aptamers have been evolved to bind proteins which are associated with a number of disease states. Using this method, many powerful antagonists of such proteins have been found. In order for these antagonists to work in animal models of disease and in humans, it is necessary to modify the aptamers. First of all, sugar modifications of nucleoside triphosphates are necessary to render the resulting aptamers resistant to nucleases found in serum. Changing the 2'OH groups of ribose to 2'F or 2'NH2 groups yields aptamers which are long lived in blood. The relatively low molecular weight of aptamers (8000-12000) leads to rapid clearance from the blood. Aptamers can be kept in the circulation from hours to days by conjugating them to higher molecular weight vehicles. When modified, conjugated aptamers are injected into animals, they inhibit physiological functions known to be associated with their target proteins. A new approach to diagnostics is also described. Aptamer arrays on solid surfaces will become available rapidly because the SELEX protocol has been successfully automated. The use of photo-cross-linkable aptamers will allow the covalent attachment of aptamers to their cognate proteins, with very low backgrounds from other proteins in body fluids. Finally, protein staining with any reagent which distinguishes functional groups of amino acids from those of nucleic acids (and the solid support) will give a direct readout of proteins on the solid support.

[1]  B. Eaton,et al.  Ribonucleosides and RNA. , 1995, Annual review of biochemistry.

[2]  C. Vargeese,et al.  Potent 2'-amino-2'-deoxypyrimidine RNA inhibitors of basic fibroblast growth factor. , 1995, Biochemistry.

[3]  P. T. Jones,et al.  Isolation of high affinity human antibodies directly from large synthetic repertoires. , 1994, The EMBO journal.

[4]  T. Kurokawa,et al.  Molecular cloning of a novel cytokine cDNA encoding the ninth member of the fibroblast growth factor family, which has a unique secretion property , 1993, Molecular and cellular biology.

[5]  J C Cox,et al.  Automated RNA Selection , 1998, Biotechnology progress.

[6]  R. Jenison,et al.  Oligonucleotide inhibitors of P-selectin-dependent neutrophil-platelet adhesion. , 1998, Antisense & nucleic acid drug development.

[7]  O. Uhlenbeck,et al.  An RNA-protein contact determined by 5-bromouridine substitution, photocrosslinking and sequencing. , 1994, Nucleic acids research.

[8]  L. Gold,et al.  Systematic evolution of ligands by exponential enrichment: RNA ligands to bacteriophage T4 DNA polymerase. , 1990, Science.

[9]  L. Gold,et al.  The use of aptamers in large arrays for molecular diagnostics. , 1999, Molecular diagnosis : a journal devoted to the understanding of human disease through the clinical application of molecular biology.

[10]  L. Gold,et al.  Using in vitro selection to direct the covalent attachment of human immunodeficiency virus type 1 Rev protein to high-affinity RNA ligands. , 1995, Proceedings of the National Academy of Sciences of the United States of America.

[11]  D. Pode,et al.  Selective ablation of immature blood vessels in established human tumors follows vascular endothelial growth factor withdrawal. , 1999, The Journal of clinical investigation.

[12]  N. Janjić,et al.  VEGF(165) mediates glomerular endothelial repair. , 1999, The Journal of clinical investigation.

[13]  M Yarus,et al.  Diversity of oligonucleotide functions. , 1995, Annual review of biochemistry.

[14]  D. Drolet,et al.  Aptamer affinity chromatography: combinatorial chemistry applied to protein purification. , 1999, Journal of chromatography. B, Biomedical sciences and applications.

[15]  D. Moscatelli,et al.  The FGF family of growth factors and oncogenes. , 1992, Advances in cancer research.

[16]  T. Zhang,et al.  Liposome-anchored vascular endothelial growth factor aptamers. , 1998, Bioconjugate chemistry.

[17]  M. Willis,et al.  High yield photocrosslinking of a 5-iodocytidine (IC) substituted RNA to its associated protein. , 1996, Nucleic acids research.

[18]  S. Ringquist,et al.  Anti-L-selectin oligonucleotide ligands recognize CD62L-positive leukocytes: binding affinity and specificity of univalent and bivalent ligands. , 1998, Cytometry.

[19]  A. Pardi,et al.  High-resolution molecular discrimination by RNA. , 1994, Science.

[20]  J. Szostak,et al.  In vitro selection of RNA molecules that bind specific ligands , 1990, Nature.

[21]  N. Janjić,et al.  Novel approach to specific growth factor inhibition in vivo: antagonism of platelet-derived growth factor in glomerulonephritis by aptamers. , 1999, The American journal of pathology.

[22]  Andrew D. Ellington,et al.  Nucleic Acid Selection and the Challenge of Combinatorial Chemistry. , 1997, Chemical reviews.

[23]  Sheela M. Waugh,et al.  2′-Fluoropyrimidine RNA-based Aptamers to the 165-Amino Acid Form of Vascular Endothelial Growth Factor (VEGF165) , 1998, The Journal of Biological Chemistry.

[24]  L. Gold,et al.  Oligonucleotides as Research, Diagnostic, and Therapeutic Agents(*) , 1995, The Journal of Biological Chemistry.

[25]  K. Matsumoto,et al.  Cloning and characterization of an androgen-induced growth factor essential for the androgen-dependent growth of mouse mammary carcinoma cells. , 1992, Proceedings of the National Academy of Sciences of the United States of America.

[26]  S. Ringquist,et al.  Anti-L-selectin aptamers: binding characteristics, pharmacokinetic parameters, and activity against an intravascular target in vivo. , 2000, Antisense & nucleic acid drug development.

[27]  D. Darland,et al.  Blood vessel maturation: vascular development comes of age. , 1999, The Journal of clinical investigation.