title: Cell binding and internalization by filamentous phage displaying a cyclic Arg-Gly-Asp-containing peptide.
abstract: Ligands that bind mammalian cell surface integrins with high affinity can mediate cellular internalization. We show that particles of the bacteriophage fd that display the cyclic integrin-binding peptide sequence GGCRGDMFGC in a proportion of their major coat protein subunits bind to cells and are efficiently internalized. In the displayed peptide the conformation of the RGD motif is restricted within a hairpin loop formed by a disulfide bridge between the 2 cysteine residues. Cellular internalization of phage was demonstrated by confocal and non-confocal immunofluorescence microscopy of tissue-cultured cells incubated with phage particles. The phage were contained in juxtanuclear vesicles in the same serial sections as transferrin receptor but were not colocalized with the cell surface marker alkaline phosphatase. Cell binding and internalization was inhibited by preincubation of cells with the integrin-binding peptide GRGDSP, whereas the control peptide GRGESP had no inhibitory effect. These results indicate that cyclic integrin-binding peptides can be used to target and enter cells and that it should be possible to exploit such peptides for the introduction of DNA, drugs, or other macromolecules.
authors.affiliation: Department of Biochemistry and Molecular Genetics, St. Mary's Hospital Medical School, London, United Kingdom.
authors.forename: S L
authors.initials: SL
authors.lastname: Hart
authors.forename: A M
authors.initials: AM
authors.lastname: Knight
authors.forename: R P
authors.initials: RP
authors.lastname: Harbottle
authors.forename: A
authors.initials: A
authors.lastname: Mistry
authors.forename: H D
authors.initials: HD
authors.lastname: Hunger
authors.forename: D F
authors.initials: DF
authors.lastname: Cutler
authors.forename: R
authors.initials: R
authors.lastname: Williamson
authors.forename: C
authors.initials: C
authors.lastname: Coutelle
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002213:Capsid / Q000737:chemistry / Q000378:metabolism*; D036022:Capsid Proteins; D002448:Cell Adhesion; D002460:Cell Line; D006801:Humans; D017912:Inovirus / Q000378:metabolism*; D016023:Integrins / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D009842:Oligopeptides / Q000737:chemistry / Q000378:metabolism*; D010456:Peptides, Cyclic / Q000737:chemistry / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism
chemical_list: D036022:Capsid Proteins; C087092:GGCRGDMFGC peptide; D016023:Integrins; D009838:Oligodeoxyribonucleotides; D009842:Oligopeptides; D010456:Peptides, Cyclic; D011993:Recombinant Fusion Proteins; C047981:arginyl-glycyl-aspartic acid; C058161:glycyl-arginyl-glycyl-aspartyl-seryl-proline; C058347:glycyl-arginyl-glycyl-glutamyl-seryl-proline