ENHANCED ANTISENSE INHIBITION OF HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 IN CELL-CULTURES BY DLS DELIVERY SYSTEM

The relatively poor cell uptake of oligonucleotides and subsequent tra nsport to the cytoplasm and nucleus is the main limitation in antisens e therapeutics. The use of lipid-based carrier system is one of the mo st promising approaches to overcome these problems. In this study, we report the use of a new lipidic formulation to deliver a phosphorothio ate oligonucleotide antisense directed against the regulatory gene rev of the HIV-1 genome and its application to the inhibition of HIV-1 in different cell culture models. Antiviral activity of either DLS-compl exed or non-complexed oligonucleotides (ODNs) was compared in acutely and chronically infected cells. We have demonstrated that substantial antisense activity could be achieved at subnanomolar concentrations wi th DLS-complexed ODN in both acute and chronic infection systems. DLS- association highly improved inhibitory activity of the antisense ODN i n acutely infected Molt-3 cells (100-fold) and primary cells (1000-fol d) and in chronically infected H9 cells (1 500 000-fold). We have show n that anti-HIV activity of phosphorothioate ODNs can be strongly enha nced by using the DLS carrier system. (C) 1997 Academic Press.