Research

Efficient inhibition of HIV-1 expression by LNA modified antisense oligonucleotides and DNAzymes targeted to functionally selected binding sites

Martin R Jakobsen^1* , Joost Haasnoot^2* , Jesper Wengel³ , Ben Berkhout² and Jørgen Kjems¹

¹  Department of Molecular Biology, University of Aarhus C.F. Møllers Allé, building 130, DK-8000 Århus C, Denmark

²  Department of Human Retrovirology Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands

³  Department of Chemistry, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark

author email corresponding author email* Contributed equally

Retrovirology 2007, 4:29doi:10.1186/1742-4690-4-29

Published:	26 April 2007

Abstract

Background

A primary concern when targeting HIV-1 RNA by means of antisense related technologies is the accessibility of the targets. Using a library selection approach to define the most accessible sites for 20-mer oligonucleotides annealing within the highly structured 5'-UTR of the HIV-1 genome we have shown that there are at least four optimal targets available.

Results

The biological effect of antisense DNA and LNA oligonucleotides, DNA- and LNAzymes targeted to the four most accessible sites was tested for their abilities to block reverse transcription and dimerization of the HIV-1 RNA template in vitro, and to suppress HIV-1 production in cell culture. The neutralization of HIV-1 expression declined in the following order: antisense LNA > LNAzymes > DNAzymes and antisense DNA. The LNA modifications strongly enhanced the in vivo inhibitory activity of all the antisense constructs and some of the DNAzymes. Notably, two of the LNA modified antisense oligonucleotides inhibited HIV-1 production in cell culture very efficiently at concentration as low as 4 nM.

Conclusion

LNAs targeted to experimentally selected binding sites can function as very potent inhibitors of HIV-1 expression in cell culture and may potentially be developed as antiviral drug in patients.