title: Improved tumour targeting by disulphide stabilized diabodies expressed in Pichia pastoris.
abstract: Diabodies are dimeric antibody fragments held together by associated heavy and light chain variable domains present on different polypeptide chains. To improve their stability we have introduced cysteine residues into the V-domains to promote the disulphide crosslinking of the dimer. A crosslinked bivalent diabody against carcinoembryonic antigen (CEA) and a crosslinked bispecific diabody against CEA and the T-cell co-receptor CD3 were expressed from Pichia pastoris and Escherichia coli by secretion. From Pichia (but not E.coli) the chains were almost quantitatively crosslinked. Compared with the parent diabodies both crosslinked diabodies were more stable to heat (by >7 degrees C) and the crosslinked bivalent diabody showed improved localization to CEA+ human tumour xenografts in nude mice.
authors.affiliation: Cambridge Antibody Technology Ltd, Melbourn, Cambridgeshire, UK.
authors.forename: K
authors.initials: K
authors.lastname: FitzGerald
authors.forename: P
authors.initials: P
authors.lastname: Holliger
authors.forename: G
authors.initials: G
authors.lastname: Winter
mesh_terms: D000818:Animals; D018033:Antibodies, Bispecific / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D000915:Antibody Affinity; D001483:Base Sequence; D017252:CD3 Complex / Q000276:immunology*; D002272:Carcinoembryonic Antigen / Q000276:immunology*; D003110:Colonic Neoplasms / Q000175:diagnosis / Q000276:immunology*; D003602:Cytotoxicity, Immunologic / Q000235:genetics; D017931:DNA Primers / Q000737:chemistry; D004220:Disulfides / Q000737:chemistry; D004926:Escherichia coli / Q000235:genetics; D015966:Gene Expression Regulation, Fungal / Q000235:genetics; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D010843:Pichia / Q000235:genetics; D017510:Protein Folding; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013696:Temperature
chemical_list: D018033:Antibodies, Bispecific; D017252:CD3 Complex; D002272:Carcinoembryonic Antigen; D017931:DNA Primers; D004220:Disulfides; D011994:Recombinant Proteins