Selecting appropriate hosts for recombinant proteins production: Review article

In recent years, the number of recombinant proteins used for therapeutic applications and industry has increased dramatically. Recombinant proteins are produced in many host organisms (microbial, insect, plant and mammalian cells). There are many factors to consider when choosing the optimal system for protein expression and purification including the mass, purity or solubility of the recombinant protein, its number of disulphide bonds, the types of post-translational modifications desired, the destination of the expressed protein, the cost and simplicity of the recombinant protein production system and finally regulatory aspects in the case of pharmaceutical production. If a soluble, non-toxic protein needs to be produced, bacteria are the first choice. However, if a complex post-translational modification is required, eukaryotic cells have to be the expression host. E. coli, Saccharomyces cerevisiae and mammalian cell lines containing Baby Hamster Kidney (BHK), Chinese Hamster Ovary (CHO) and hybridoma cells are main host systems for production of most antibodies and proteins for diagnostic and therapeutic use. There is not general expression host system to act optimally for all recombinant proteins. Therefore, several expression host system must be experimentally evaluated for each recombinant protein.