2022 - Downstream Process Development of a Complicated Fusion Protein

The number and variety of protein therapeutics have increased dramatically in recent years, and they now play a significant role in various fields of medicine. To satisfy therapeutic demand, these molecules must be produced at large scale in mammalian or bacterial cell hosts; but with the greater variety in protein therapeutic molecules, comes greater challenges in purifying complicated molecules to a level of quality that is required, with a process that is scalable. In this webinar, the featured speaker presents process development approaches used to overcome challenges in the recovery of a bioactive multi-unit fusion protein.
Overexpression of proteins in a bacterial host often leads to the formation of inclusion bodies, which presents a major challenge for large scale recovery of bioactive material; the process of purifying proteins from inclusion bodies can be laborious and the yields are often low. A greater challenge is the need to recover bioactive proteins with a high content of cysteines. The formation of random intra- and intermolecular disulfide bonds during protein biogenesis can cause many challenges to the purification of pure, active protein, including protein misfolding, oligomerization and aggregation.
The bioactive form of the protein of interest is a monomer, but because of several cysteines in the sequence, this fusion protein can form monomers in several conformations, as well as dimers, and higher order complexes during refolding stage, with some of the monomeric conformers having higher activity than others. The speaker concentrated on the optimization of a purification process —which would produce an increased yield of the most active monomeric conformer while minimizing the presence of other protein forms — more specifically, the solubilization process from inclusion bodies, protein refolding and further purification of the bioactive monomer using column chromatography.
The speaker will present data from small-scale solubilization and refold studies, which were employed to discover optimized conditions for parameters such as buffer formulation as well as incubation time and temperature. The presented data will also help determine operating parameters for purification by column chromatography, which were found to be critical for minimizing formation of higher order complexes during processing.
Join this webinar to learn about challenges faced during the downstream process development of a complicated fusion protein and how to address them.