Abstract:
Anti-RANKL monoclonal antibody is a fully human monoclonal antibody (mAb) available for treatment of osteoporosis. In this study, anti-RANKL mAb was transiently expressed using the Geminiviral expression system in Nicotiana benthamiana. Moreover, the structure of plant-produced mAb was characterized and functional activity was also determined. The result indicated that anti-RANKL mAb was produced with the maximum expression level on 8 days post infiltration and estimated to be 0.5 mg/g leaf fresh weight. The recombinant mAb from crude extracts was purified by using protein A affinity column chromatography. The plant-produced mAb provided in vitro affinity binding with human RANKL, determined by RANKL-ELISA binding. The function of plant-produced mAb was evaluated in vitro. CD14 positive cells isolated from human peripheral blood mononuclear cells (PBMCs) were cultured in vitro in the presence of human RANKL and macrophage colony-stimulating factor (M-CSF) in order for stimulating osteoclastogenesis. The results demonstrated that plant-produced mAb could significantly decrease the number of osteoclasts compared to commercially available denosumab. These results demonstrated that the plant-produced mAb has the potential to inhibit the osteoclast differentiation and can be applied for the osteoporosis treatment.