title: An antibody produced in tobacco expressing a hybrid beta-1,4-galactosyltransferase is essentially devoid of plant carbohydrate epitopes.
abstract: N-glycosylation of a mAb may have a major impact on its therapeutic merits. Here, we demonstrate that expression of a hybrid enzyme (called xylGalT), consisting of the N-terminal domain of Arabidopsis thaliana xylosyltransferase and the catalytic domain of human beta-1,4-galactosyltransferase I (GalT), in tobacco causes a sharp reduction of N-glycans with potentially immunogenic core-bound xylose (Xyl) and fucose (Fuc) residues as shown by Western blot and MALDI-TOF MS analysis. A radioallergosorbent test inhibition assay with proteins purified from leaves of WT and these transgenic tobacco plants using sera from allergic patients suggests a significant reduction of potential immunogenicity of xylGalT proteins. A mAb purified from leaves of plants expressing xylGalT displayed an N-glycan profile that featured high levels of galactose, undetectable xylose, and a trace of fucose. Hence, a transgenic plant expressing the hybrid GalT might yield more effective and safer monoclonals for therapeutic purposes than WT plants and even transgenic plants expressing the unchanged GalT.
authors: Business Unit Bioscience, Plant Research International, Wageningen University and Research Center, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands.
authors: Hans
authors: H
authors: Bakker
authors: Gerard J A
authors: GJ
authors: Rouwendal
authors: Anton S
authors: AS
authors: Karnoup
authors: Dion E A
authors: DE
authors: Florack
authors: Geert M
authors: GM
authors: Stoopen
authors: Johannes P F G
authors: JP
authors: Helsper
authors: Ronald
authors: R
authors: van Ree
authors: Irma
authors: I
authors: van Die
authors: Dirk
authors: D
authors: Bosch