RESISTANCE TO HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 INFECTION CONFERRED BY TRANSDUCTION OF HUMAN PERIPHERAL-BLOOD LYMPHOCYTES WITH RIBOZYME, ANTISENSE, OR POLYMERIC TRANSACTIVATION RESPONSE ELEMENT CONSTRUCTS

Human peripheral blood lymphocytes (PBLs) were transduced with a number of recombinant retroviruses including RRz2, an LNL6-based virus with a ribozyme targeted to the human immunodeficiency virus (HIV) tat gene transcript inserted within the 3' region of the neomycin-resistance gene; RASH5, an LNHL-based virus containing an antisense sequence to the 5' leader region of HIV-1 downstream of the human cytomegalovirus promoter; and R20TAR, an LXSN-based virus with 20 tandem copies of the HIV-1 trans-activation response element sequence driven by the Moloney murine leukemia virus long terminal repeat. After G418 selection, transduced PBLs were challenged with the HIV-1 laboratory strain IIIB and a primary clinical isolate of HIV-1, 82H. Results showed that PBLs from different donors could be transduced and that this conferred resistance to HIV-1 infection. For each of the constructs, a reduction of approximate to 70% in p24 antigen level relative to the corresponding control-vector-transduced PBLs was observed. Molecular analyses showed constitutive expression of all the transduced genes from the retroviral long terminal repeat, but no detectable transcript was seen from the internal human cytomegalovirus promoter for the antisense construct. Transduction of, and consequent transgene expression in, PBLs did not impact on the surface expression of either CD4(+)/CD8(+) (measured by flow cytometry) or on cell doubting time (examined by [H-3] thymidine uptake). These results indicate the potential utility of these anti-HIV-1 gene therapeutic agents and show the preclinical value of this PBL assay system.