title: Inhibition of expression of the Galalpha1-3Gal epitope on porcine cells using an intracellular single-chain antibody directed against alpha1,3galactosyltransferase.
abstract: The carbohydrate epitope Galalpha1-3Gal has been shown to be the major target of natural antibodies responsible for hyperacute rejection of porcine tissues transplanted into primates. We have sought to produce a phenotypic knockout of the alpha1, 3Galactosyltransferase enzyme that is responsible for generating this epitope, using an intracellular antibody approach. We have isolated high affinity anti-alpha1,3Galactosyltransferase single-chain antibodies from a semi-synthetic phage display library. Expression of a KDEL-tagged anti-alpha1,3Galactosyltransferase single-chain antibody in a porcine endothelial cell line resulted in the decreased expression of the Galalpha1-3Gal epitope and increased resistance to lysis by human serum.
authors.affiliation: Department of Immunology, Division of Medicine, Imperial College School of Medicine, Hammersmith Campus, Du Cane Road, London, UK.
authors.forename: A
authors.initials: A
authors.lastname: Sepp
authors.forename: C A
authors.initials: CA
authors.lastname: Farrar
authors.forename: T
authors.initials: T
authors.lastname: Dorling
authors.forename: T
authors.initials: T
authors.lastname: Cairns
authors.forename: A J
authors.initials: AJ
authors.lastname: George
authors.forename: R I
authors.initials: RI
authors.lastname: Lechler
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D002478:Cells, Cultured; D003001:Cloning, Molecular; D003165:Complement System Proteins / Q000276:immunology; D004187:Disaccharides / Q000235:genetics*; D018985:Epitopes, B-Lymphocyte / Q000235:genetics*; D005700:Galactosyltransferases / Q000276:immunology*; D005786:Gene Expression Regulation; D006801:Humans; D007128:Immunoglobulin Fragments / Q000235:genetics* / Q000276:immunology; D007135:Immunoglobulin Variable Region / Q000235:genetics / Q000276:immunology; D007424:Intracellular Fluid; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000235:genetics; D019151:Peptide Library; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology; D013552:Swine
chemical_list: D004187:Disaccharides; D018985:Epitopes, B-Lymphocyte; D007128:Immunoglobulin Fragments; D007135:Immunoglobulin Variable Region; D009842:Oligopeptides; D019151:Peptide Library; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins; C073762:lysyl-aspartyl-glutamyl-leucine; C055075:galactosyl-(1-3)galactose; D003165:Complement System Proteins; D005700:Galactosyltransferases; C047006:N-acetyllactosaminide alpha-1,3-galactosyltransferase