Comparative Analysis of the Expression Systems and Production Platforms

Novoplant is developing, for the first time, a comprehensive portfolio of antibodies for use in veterinary medicines. These monoclonal immunoglobulin preparations are based on single-chain-anti-bodies produced in plant seeds, and are designed to combat typical diseases that occur in swine, poultry, and calves in animal husbandry. They are designed to offer protection against coccidiosis in chickens and scour caused by ETEC Escherichia coli, rotavims and coronavirus in piglets and calves. 

Medicago currently has 10 Mabs and plasma-proteins in early-stage development, with preclinical studies planned to start in 2005 for two products. Greenova-tion has one antibody (ABC-48) in preclinical development for the prevention of deep-vein thrombosis. The secreted IgG antibody was shown to he correctly assembled, and displayed normal binding activity to its natural ligand. 

This brief account of currently available products and under development (see Table 6.4) provides evidence that, despite several drawbacks, the production of recombinant proteins in plants is steadily progressing. However, it is also evident that all expression platforms in use have certain 

Comparative Analysis of the Expression Systems and Production Platforms 

Once the expression cassette has been optimized, highly diluted agrobacterial suspension carrying the cDNA of the TMV-based vector is used for large-scale agroinfiltration of whole tobacco plants. The biomass can be harvested 7-10 days later and used for isolation of the recombinant protein of interest. In comparison with other systems, this protocol is extremely fast, provides high yields, and has the potential for unlimited scalability. In addition, our 

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