Development of a nonintegrating Rev-dependent lentiviral vector carrying diphtheria toxin A chain and human TRAF6 to target HIV reservoirs

Gene Ther. 2010 Sep;17(9):1063-76. doi: 10.1038/gt.2010.53. Epub 2010 Apr 22.

Abstract

Persistence of human immunodeficiency virus (HIV) despite highly active antiretroviral therapy (HAART) is a lasting challenge to virus eradication. To develop a strategy complementary to HAART, we constructed a series of Rev-dependent lentiviral vectors carrying diphtheria toxin A chain (DT-A) and its attenuated mutants, as well as human tumor necrosis factor receptor-associated factor 6 (TRAF6). Expression of these suicide genes following delivery through viral particles is dependent on Rev, which exists only in infected cells. Among these toxins, DT-A has been known to trigger cell death with as little as a single molecule, whereas two of the attenuated mutants in this study, DT-A(176) and DT-A(Delta N), were well tolerated by cells at low levels. TRAF6 induced apoptosis only with persistent overexpression. Thus, these suicide genes, which induce cell death at different expression levels, offer a balance between efficacy and safety. To minimize possible mutagenesis introduced by retroviral integration in nontarget cells, we further developed a nonintegrating Rev-dependent (NIRD) lentiviral vector to deliver these genes. In addition, we constructed a DT-A-resistant human cell line by introducing a human elongation factor 2 mutant into HEK293T cells. This allowed us to manufacture the first high-titer NIRD lentiviral particles carrying DT-A to target HIV-positive cells.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis
  • Cell Death
  • Cell Line
  • DNA, Viral / metabolism
  • Diphtheria Toxin / genetics*
  • Diphtheria Toxin / metabolism
  • Fluoroimmunoassay
  • Gene Products, rev / genetics*
  • Genetic Therapy / methods
  • Genetic Vectors / genetics*
  • Genetic Vectors / metabolism
  • HIV Infections / genetics
  • HIV-1 / genetics
  • HIV-1 / physiology*
  • Humans
  • Lentivirus / genetics*
  • Lentivirus / metabolism
  • Peptide Fragments / genetics*
  • Peptide Fragments / metabolism
  • TNF Receptor-Associated Factor 6 / genetics*
  • TNF Receptor-Associated Factor 6 / metabolism
  • Virus Replication / physiology

Substances

  • DNA, Viral
  • Diphtheria Toxin
  • Gene Products, rev
  • Peptide Fragments
  • TNF Receptor-Associated Factor 6
  • diphtheria toxin fragment A