Patent ID: 6919442

Claim:
An isolated post-transcriptional regulatory element (PRE) nucleic acid comprising SEQ ID NO:1, the PRE nucleic acid defined as having the following property: the PRE nucleic acid, when inserted in a recombinant, hybrid human immunodeficiency virus (HIV)-1 lacking or having a non-functional wild-type post-transcriptional RNA nucleo-cytoplasrnic transport element (NCTE), functions as a NCTE in the hybrid HIV-1, and when the PRE-containing hybrid HIV-1 virus infects activated human peripheral blood mononuclear cells (huPBMCs), the level of expression of HIV-1 p24 gag is between about 5 fold and about 200 fold less than levels of p24 gag expression when HIV-1 wild type virus, utilizing wild-type NCTE, infects activated huPBMCs.