PROPERTIES AND ANTI-HIV ACTIVITY OF HAIRPIN ANTISENSE OLIGONUCLEOTIDES CONTAINING 2'-METHOXYNUCLEOSIDES WITH BASE-PAIRING IN THE STEM REGION AT THE 3'-END

A new type of hairpin antisense oligodeoxyribo-nucleotide, containing 2'-methoxynucleosides with base-pairing in the stem region at the 3'-e nd, was tested for 3'-exonuclease resistance and anti-HIV activity. An increased resistance to nuclease degradation has been observed by inc ubation of the hairpin oligo-nucleotides with DNA polymerase and foeta l bovine serum. Of particular interest is the hairpin antisense oligon ucleotide containing 2'-methoxynucleosides with base-pairing in the st em region at the 3'-end, which has increased nuclease resistance and h ybridizes effectively with a complementary RNA. Furthermore, these com pounds were assayed for inhibition of virus replication in HIV-1 infec ted MT-4 cells. In the anti-HIV activity test, the hairpin oligonucleo tide phosphorothioate derivatives showed higher anti-HIV activities co mpared to their linear counterparts.