Document 0725
 DOCN  M9550725
 TI    Purified GPI-anchored CD4DAF as a receptor for HIV-mediated gene
       transfer.
 DT    9505
 AU    Brodsky RA; Jane SM; Vanin EF; Mitsuya H; Peters TR; Shimada T; Medof
       ME; Nienhuis AW; Johns Hopkins University Oncology Center, Baltimore, MD
       21205.
 SO    Hum Gene Ther. 1994 Oct;5(10):1231-9. Unique Identifier : AIDSLINE
       MED/95151838
 AB    CD4 is the major cellular receptor for the human immunodeficiency virus
       (HIV). A hybrid gene encoding the extracellular domains of CD4, linked
       to the sequence encoding the membrane attachment region of the
       glycosylphosphatidylinositol (GPI)-anchored protein decay accelerating
       factor (DAF) was stably transfected into HeLa cells. The resultant cell
       line (T4HD) expressed GPI-anchored CD4DAF at high levels and was
       susceptible to gene transfer with a recombinant HIV vector. In an effort
       to expand the spectrum of cells susceptible to HIV gene transfer, CD4DAF
       was released from the surface of the T4HD cell line by detergent lysis,
       purified by immunoaffinity chromatography, and reincorporated into
       native HeLa cells. Incorporation occurred via the GPI anchor as
       evidenced by cleavage with phosphatidylinositol-specific phospholipase
       C. More than 95% of the CD4DAF-treated HeLa cells were CD4-positive by
       flow cytometry, and kinetic analysis demonstrated that over 75% of the
       fusion protein remained anchored to the cell membrane after 90 min at 37
       degrees C. The purified protein retained its ability to bind the
       envelope protein of HIV. When incorporated, it bound fluorescein
       isothiocyanate (FITC)-conjugated gp120, and in its soluble form blocked
       transduction of CD4-positive cells incubated with an HIV-derived vector
       containing the Neo gene. In contrast to the T4HD cells, exposure of
       CD4DAF-treated cells to the Neo HIV vector yielded only transient
       neomycin-resistant colonies. These results suggest that endogenous
       synthesis of the CD4 molecule may be necessary for successful HIV
       genomic integration.
 DE    Antigens, CD/*METABOLISM  Antigens, CD4/*METABOLISM  Cell Line  Chimeric
       Proteins/*METABOLISM  *Gene Transfer
       Glycosylphosphatidylinositols/*PHYSIOLOGY  Hela Cells  Human
       HIV/*GENETICS  HIV Envelope Protein gp120/METABOLISM  Membrane
       Glycoproteins/*METABOLISM  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).