title: Protein scaffold and expression level determine antiviral activity of membrane-anchored antiviral peptides.
abstract: Cell membrane-anchored (ma) antiviral peptides derived from the C-terminal heptad repeat of the HIV-1 transmembrane glycoprotein gp41 (C-peptides) and expressed from retroviral vectors were shown to efficiently inhibit HIV-1 entry into target cells. Here, we analyzed the influence of the vector backbone, the scaffold modules that anchor the peptide to the membrane and the length of the C-peptide on expression level and antiviral activity. In general, antiviral activity was determined primarily by the density of the C-peptide on the cell surface. By influencing expression levels, the scaffold elements indirectly also determined antiviral activity. Additional direct effects of the scaffold on antiviral activity were minor. At comparable expression levels, the elongated C-peptide (maC46) was found to be more potent than the shorter maC36. On the basis of these findings, a dose-response assay was established that quantifies antiviral activity relative to the expression level of the antiviral gene product. Taken together, these data demonstrate the importance of analyzing the efficacy of therapeutic genes relative to the dose of the gene product.
authors.affiliation: Applied Virology and Gene Therapy, Georg-Speyer-Haus, 60596 Frankfurt am Main, Germany.
authors.forename: Felix G
authors.initials: FG
authors.lastname: Hermann
authors.forename: Holger
authors.initials: H
authors.lastname: Martinius
authors.forename: Marc
authors.initials: M
authors.lastname: Egelhofer
authors.forename: Tsanan
authors.initials: T
authors.lastname: Giroglou
authors.forename: Torsten
authors.initials: T
authors.lastname: Tonn
authors.forename: Stefanie D
authors.initials: SD
authors.lastname: Roth
authors.forename: Roland
authors.initials: R
authors.lastname: Zahn
authors.forename: Patricia
authors.initials: P
authors.lastname: Schult-Dietrich
authors.forename: Alexander
authors.initials: A
authors.lastname: Alexandrov
authors.forename: Ursula
authors.initials: U
authors.lastname: Dietrich
authors.forename: Christopher
authors.initials: C
authors.lastname: Baum
authors.forename: Dorothee
authors.initials: D
authors.lastname: von Laer
mesh_terms: D000595:Amino Acid Sequence; D000998:Antiviral Agents / Q000494:pharmacology*; D002096:C-Peptide / Q000737:chemistry / Q000494:pharmacology*; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005822:Genetic Vectors / Q000235:genetics; D015658:HIV Infections / Q000821:virology; D006801:Humans; D008969:Molecular Sequence Data; D011506:Proteins / Q000378:metabolism*; D012190:Retroviridae / Q000235:genetics; D019076:Transgenes; D053586:Virus Internalization / Q000187:drug effects
chemical_list: D000998:Antiviral Agents; D002096:C-Peptide; D011506:Proteins