Lentiviral vectors (LVV) are widely used in an increasing number of approved cell and gene therapies, and benchmarking is important in evaluating production processes and products. We have produced a lentiviral vector reference material (LVV-RM) that expresses the common marker gene (green fluorescent protein [GFP]) to enable data comparisons and support LVV research programs. To generate that reference material, we have applied our previously developed fed-batch process to a 100 L production using an inducible LVV-producer cell line. The LVV material was harvested three days post-induction from a 200 L single-use bioreactor. A downstream purification process was also developed and scaled-up to meet production requirements: It consisted of nuclease digestion, clarification by depth filtration, chromatography capture using CIM-QA monolith anion exchangers, and ultrafiltration/diafiltration using a hollow fiber membrane prior to bulk-filling the final product. A total of 4.4 L of diafiltered and concentrated LVV product was obtained (9.2 E10 particles/mL, 3.6 E7 TU/mL) and stored at -80°C. Nearly 8000 vials are now available to the LVV community via the American Type Culture Collection (ATCC).
Category: <span>Chromatography</span>
The purification of PHB-01 plantibody derived from tobacco leaves imposed difficulties when the plantibody solid-liquid extraction design was performed. Thus, our study focused on assessing a combination of an aqueous two-phase extraction (ATPE) procedure and affinity chromatography for solving some of the issues in plantibody purification. This was done using a complete factorial redesign, different polyethylene glycol (PEG)/K2PO4 proportions, and pH values in each partitioning variant.
Agarose-based chromatography beads were first introduced by Stellan Hjertén in 1962. Fifty years later, beaded agarose has become the dominant resin for protein purification and is extensively used, ranging from research-scale in sub mL volumes to full-scale manufacturing in > 500 L chromatography columns. Recent resin development work has focused on increasing capacity and selectivity through different grafting technologies and ligand developments.