b"GE Plants in a COVID-19 Vaccine? Maybe!Everyones frantically looking for a COVID-19 vaccine, but could genetically engineered plants be the solution?Joe FunkVACCINATION IS ONEof the most effective public healthticals. A diverse group of biopharmaceuticals, including antibod-interventions of the 20th century. In recent decades, recombi- ies, vaccines, growth factors, and cytokines have been produced nant technologies have enabled the design of experimental vac- in plant systems. A recombinant enzyme produced in carrot cines against a wide range of diseases using plant viruses andcells, for example, has been approved by the U.S. Food and Drug virus-like particles as central elements to stimulate protectiveAdministration for replacement therapy treatment of Gaucher's and long-lasting immune responses. At least 71 vaccines againstdisease, a genetic enzyme deficiency. The main advantages of infectious agents have been constructed based on plant viruses.plant-based platforms include their inability to replicate human Several plant viruses have already been used for the develop- pathogens. This requires less strident efforts to diminish the risk ment of vaccine platforms, which have been tested in humanof contamination during the purification process. Plant-based and animal studies, suggesting that plant virus-based vaccinesplatforms also require less sophisticated bioreactors for efficient will be introduced into clinical practice soon. synthesis of complex proteins.Currently, there is no vaccine ready for any coronavirus. SARSPlant-based vaccines are gradually becoming a reality, and MERS, caused by different coronavirus strains, were con- although progress has been slower than expected. Slow pro-trolled with isolation and quarantine. The efforts to develop vac- gress is particularly true for the development of oral vaccines, cines for these two viral diseases came to a halt for lack of activewith the main drawbacks being a poor characterization of anti-cases as the diseases died out. gen stability, bioavailability and reproducibility. The new coronavirus strain 2019 (COVID-19), caused by theInjectable vaccines could be produced by using transient severe acute respiratory syndrome virus (SARS-CoV-2), hasexpression systems, which offer the highest protein yields and quickly spread around the globe. It has caused the worst pan- are already adopted at the industrial level to produce virus-like demic since the Spanish Flu of 1918. As of press time, there is noparticle (VLPs) vaccines and other biopharmaceuticals under specific treatment for COVID-19. Epidemiologists at the WorldGMPC-processes. Health Organization (WHO) and other disease control centersStably transformed plants are another option, but this say containing this pandemic demands rapid development ofapproach requires more time for the development of antigen-drugs and vaccines. Plant-based vaccines are a technology withproducing lines. Nonetheless, this approach offers the possibility proven viability, which has led to promising results for candidatesof developing oral vaccines in which the plant cell could act as evaluated at the clinical level, meaning this technology couldthe antigen delivery agent. This is the most attractive approach contribute towards the fight against COVID-19. in terms of cost, easy delivery and neutralizing the pathogen before it can cause infection. Plant-based VaccinesAs research groups are developing vaccines to fight the pan- Tobacco-Sourced Vaccinesdemic, they need a method to produce these vaccines quickly,An international team of scientists from the Institute of Plant in large amounts and at a low cost. One potential solution is toMolecular and Cellular Biology (IBMCP), Valencia, Spain, has use plants as bio-factories. The genes to produce the vaccinemade the sequence of the Nicotiana benthamiana genome can be transferred quickly and temporarily to plants that can beavailable to international researchers. Commonly referred to as grown and harvested using simple and safe farming techniques. bentha, it is a close relative of cultivated tobacco. Bentha is cur-Genetically engineered plants have been used for more thanrently used by several researchers as a bio-factory for experi-30 years to provide a platform for manufacturing biopharmaceu- mental vaccines against SARS-COV-2. 6/ SEEDWORLD.COMSEPTEMBER 2020"