title: Design and development of thermolytic DNA oligonucleotide prodrugs.
abstract: Deoxyribonucleoside phosphoramidites functionalized with the thermolytic 2-(N-formyl-N-methyl)aminoethyl group for phosphorus protection (1a-d) have been prepared and employed in the solid-phase synthesis of CpG ODN fma1555. Given that this modified oligonucleotide can be converted to the immunomodulatory CpG ODN 1555 under neutral conditions at 37 degrees C, its biologic activity was demonstrated in vivo by studies showing that intraperitoneal administration of CpG ODN fma1555 in mice resulted in the activation of cytokine-secreting splenocytes. Furthermore, administration of CpG ODN fma1555 to mice that were challenged intradermally in the ear with live L. major metacyclic promastigotes, reduced the severity of Leishmania skin lesions over time to an extent similar to that obtained with CpG ODN 1555. In another infectious model experiment, CpG ODN fma1555 protected newborn mice from death (65% survival) when administered 3 days before infection with the aggressive Tacaribe (TCRV) virus. A comparable immunoprotection was obtained by treatment of TCRV-infected mice with CpG ODN 1555 administered on the same day of infection (45% survival). However, when TCRV-infected mice were treated with CpG ODN fma1555 on the day of infection, they died as a consequence of the relatively slow conversion of the oligonucleotide prodrug to the bioactive CpG ODN 1555. Co-administration of both CpG ODN 1555 and CpG ODN fma1555 to mice 3 days prior to TCRV infection or on the day of infection provided protection from death (45-65% survival) and thus widened the immunoprotection window against TCRV-infection.
authors.affiliation: Laboratory of Chemistry, Division of Therapeutic Proteins, Center for Drug Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892, USA.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Grajkowski
authors.forename: Joao
authors.initials: J
authors.lastname: Pedras-Vasconcelos
authors.forename: Cristina
authors.initials: C
authors.lastname: Ausín
authors.forename: Daniela
authors.initials: D
authors.lastname: Verthelyi
authors.forename: Serge L
authors.initials: SL
authors.lastname: Beaucage
mesh_terms: D000818:Animals; D004247:DNA / Q000737:chemistry*; D015195:Drug Design; D006801:Humans; D018320:Leishmania major / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008956:Models, Chemical; D009362:Neoplasm Metastasis; D009838:Oligodeoxyribonucleotides / Q000737:chemistry*; D009841:Oligonucleotides / Q000737:chemistry*; D011355:Prodrugs / Q000737:chemistry*
chemical_list: C408982:CPG-oligonucleotide; D009838:Oligodeoxyribonucleotides; D009841:Oligonucleotides; D011355:Prodrugs; D004247:DNA