ProductionofRecombinantProteinsinSuspensionCulturedPlantCells

Plants have emerged in the past decade as a suitable alternative to the  current production systems for recombinant pharmaceutical proteins and,  today their potential for low-cost production of high quality, much  safer and biologically active mammalian proteins is largely documented.  

Among various plant expression systems being explored, genetically  modified suspension-cultured plant cells offer a promising system for  production of biopharmaceuticals. Indeed, when compared to other  plant-based production platforms that have been explored,  suspension-cultured plant cells have the advantage of being totally  devoid of problems associated with the vagaries of weather, pest, soil  and gene flow in the environment. Because of short growth cycles, the  timescale needed for the production of recombinant proteins in plant  cell culture can be counted in days or weeks after transformation  compared to months needed for the production in transgenic plants.  Moreover, recovery and purification of recombinant proteins from plant  biomass is an expensive and technically challenging business that may  amount to 80–94% of the final product cost. One additional advantage of  plant cell culture is that the recombinant protein fused with a signal  sequence can be expressed and secreted into the culture medium, and  therefore recovered and purified in the absence of large quantities of  contaminating proteins. Consequently, the downstream processing of  proteins extracted from plant cell culture medium is less expensive,  which may/does balance the higher costs of fermentation. When needed for  clinical use, recombinant proteins are easily produced in  suspension-cultured plant cells under certified, controllable and  sterile conditions that offer improved safety and provide advantages for  good manufacturing practices and regulatory compliance.    In this chapter, we present basic protocols for rapid generation of  transgenic suspension-cultured cells of Nicotiana tabacum, Oriza sativa  and Arabidopis thaliana. These systems are powerful tools for plant-made  pharmaceuticals production in highly controlled conditions.