Impact of glycoengineering and antidrug antibodies on the anticancer activity of a plant‐made lectin‐Fc fusion protein

• Published in: Plant biotechnology journal Vol. 20; no. 11; pp. 2217 - 2230
• Main Authors: Dent, Matthew, Mayer, Katarina L., Verjan Garcia, Noel, Guo, Haixun, Kajiura, Hiroyuki, Fujiyama, Kazuhito, Matoba, Nobuyuki
• Format: Journal Article
• Language: English
• Published: Southampton John Wiley & Sons, Inc 01.11.2022; John Wiley and Sons Inc
• Subjects: Affinity; Antibodies; Anticancer properties; Antitumor activity; Apoptosis; avaren lectin; Biocompatibility; cancer immunotherapy; Cell proliferation; Cytotoxicity; Deficient mutant; Fc receptors; Fusion protein; Glycan; In vivo methods and tests; Intravenous administration; lectibody; Liquid chromatography; Lung cancer; Mannose; Manufacturing; Melanoma; Metastases; Molecular weight; Monoclonal antibodies; Mutation; Nicotiana benthamiana; Polysaccharides; Proteins; Receptors; Toxicity; Tumors; tumour‐associated carbohydrate antigen
• ISSN: 1467-7644; 1467-7652
• DOI: 10.1111/pbi.13902

Summary Plants are an efficient production platform for manufacturing glycoengineered monoclonal antibodies and antibody‐like molecules. Avaren‐Fc (AvFc) is a lectin‐Fc fusion protein or lectibody produced in Nicotiana benthamiana, which selectively recognizes cancer‐associated high‐mannose glycans. In this study, we report the generation of a glycovariant of AvFc that is devoid of plant glycans, including the core α1,3‐fucose and β1,2‐xylose residues. The successful removal of these glycans was confirmed by glycan analysis using HPLC. This variant, AvFcΔXF, has significantly higher affinity for Fc gamma receptors and induces higher levels of luciferase expression in an antibody‐dependent cell‐mediated cytotoxicity (ADCC) reporter assay against B16F10 murine melanoma cells without inducing apoptosis or inhibiting proliferation. In the B16F10 flank tumour mouse model, we found that systemic administration of AvFcΔXF, but not an aglycosylated AvFc variant lacking affinity for Fc receptors, significantly delayed the growth of tumours, suggesting that Fc‐mediated effector functions were integral. AvFcΔXF treatment also significantly reduced lung metastasis of B16F10 upon intravenous challenge whereas a sugar‐binding‐deficient mutant failed to show efficacy. Lastly, we determined the impact of antidrug antibodies (ADAs) on drug activity in vivo by pretreating animals with AvFcΔXF before implanting tumours. Despite a significant ADA response induced by the pretreatment, we found that the activity of AvFcΔXF was unaffected by the presence of these antibodies. These results demonstrate that glycoengineering is a powerful strategy to enhance AvFc's antitumor activity. The plant‐produced lectibody Avaren‐Fc showed enhanced antitumor activity when the core fucose residue was removed from the Fc glycan. Anti‐drug antibodies appeared to augment antitumor efficacy, possibly through the lectibody's vaccinal effect.