Therapeutic recombinant protein production in plants: Challenges and opportunities

• Published in: Plants, people, planet Vol. 2; no. 2
• Main Authors: Burnett, Matthew J. B., Burnett, Angela C.
• Format: Journal Article
• Language: English
• Published: United States Wiley Blackwell (John Wiley & Sons) 28.11.2019
• Subjects: CRISPR/Cas9; ENVIRONMENTAL SCIENCES; Genetic Engineering; Plant Expression Systems; Protein; Recombinant; Therapeutic
• ISSN: 2572-2611; 2572-2611

Therapeutic recombinant proteins are a powerful tool for combating many diseases which were previously hard to treat. The most utilised expression systems are Chinese Hamster Ovary cells and E.coli, but all available expression systems have strengths and weaknesses with regards to development time, cost, protein size, yield, growth conditions, post-translational modifications and regulatory approval. The plant industry is well established and growing and harvesting crops is easy and affordable using current infrastructure. Growth conditions are simple requiring sunlight, water and the addition of cheap, available fertilizers. There are multiple options for plant expression systems including species, genetic constructs and protein targeting, each best suited to a particular type of therapeutic protein production. Transient expression systems provide a mechanism to rapidly transfect plants and produce therapeutic protein in a matter of weeks, rather than the months it takes for many competing expression systems, while proteins targeted to cereal seeds can be harvested, stored and potentially purified much more easily than in competing systems. Current challenges for plant expression systems include a lack of regulatory approval, environmental containment concerns and non-human glycosylation which may limit the scope of the type of therapeutic proteins that can be manufactured in plants. The specific strengths of plant expression systems could facilitate the production of certain therapeutic proteins quickly and cheaply in the near future.