title: Intracellular antibodies as a new class of therapeutic molecules for gene therapy.
abstract: Intracellularly expressed antibodies, referred to as "intrabodies" can be designed to bind and inactivate target molecules inside cells. In our previous study, mammalian cells were transduced to produce an anti-gp120 single-chain intrabody sFv105 to inactivate human immunodeficiency virus type-1 (HIV-1) infection. Here, an inducible expression vector was constructed in which the sFv105 intrabody, which reacts with the CD4-binding site of HIV-1 gp120, is under the control of the HIV-1 long terminal repeat (LTR)/promoter. The sFv105 intrabody is inducibly expressed after HIV-1 infection or in the presence of Tat protein and is retained intracellularly. A human CD4+ lymphocyte line transformed with the expression vector exhibits resistance to the virus-mediated syncytium formation and a decreased ability to support HIV-1 production. Surface gp120 expression is markedly reduced and surface CD4 is restored to normal following HIV-1 infection in the transformed lymphocytes. Cell-surface phenotype, replication rate, morphology, and response to mitogenic stimulation of the transformed cells are also normal. Thus, intrabodies are a new class of active molecules that may be useful for the gene therapy of acquired immunodeficiency virus (AIDS) and other diseases.
authors.affiliation: Dana-Farber Cancer Institute, Department of Pathology, Harvard Medical School, Boston, MA 02115.
authors.forename: S Y
authors.initials: SY
authors.lastname: Chen
authors.forename: J
authors.initials: J
authors.lastname: Bagley
authors.forename: W A
authors.initials: WA
authors.lastname: Marasco
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology / Q000517:prevention & control / Q000628:therapy*; D000914:Antibodies, Viral / Q000032:analysis / Q000276:immunology* / Q000627:therapeutic use; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000382:microbiology; D002461:Cell Line, Transformed; D005456:Fluorescent Dyes; D015316:Genetic Therapy; D005822:Genetic Vectors / Q000235:genetics / Q000276:immunology; D015699:HIV Envelope Protein gp120 / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology*; D006801:Humans
chemical_list: D000914:Antibodies, Viral; D005456:Fluorescent Dyes; D015699:HIV Envelope Protein gp120