Function and glycosylation of plant-derived antiviral monoclonal antibody

Plant genetic engineering led to the production of plant-derived mAb (mAb(P)), which provides a safe and economically feasible alternative to the current methods of antibody production in animal systems. In this study, the heavy and light chains of human anti-rabies mAb were expressed and assembled in planta under the control of two strong constitutive promoters. An alfalfa mosaic virus untranslated leader sequence and Lys-Asp-Glu-Leu (KDEL) endoplasmic reticulum retention signal were linked at the N and C terminus of the heavy chain, respectively. mAbP was as effective at neutralizing the activity of the rabies virus as the mammalian-derived antibody (mAb(M)) or human rabies Ig (HRIG). The mAb(P) contained mainly oligomannose type N-glycans (90%) and had no potentially antigenic alpha(1,3)-linked fucose residues. mAb(P) had a shorter half-life than mAb(M). The mAb(P) was as efficient as HRIG for post-exposure prophylaxis against rabies virus in hamsters, indicating that differences in N-glycosylation do not affect the efficacy of the antibody in this model.