Purification of a recombinant heavy chain fragment C vaccine candidate against botulinum serotype C neurotoxin [rBoNTC(H_c)] expressed in Pichia pastoris

Authors

• Michael P. Dux, Novartis Animal Health US Inc.
• Jicai Huang, Nektar Therapeutics
• Rick Barent, Intervet
• Mehmet Inan, Alder PharmaceuticalsFollow
• S. Todd Swanson, University of Nebraska-Lincoln
• Jayanta Sinha, University of Nebraska-Lincoln
• John T. Ross, DynPort Vaccine Company (DVC) LLC
• Leonard A. Smith, United States Army Medical Research and Materiel CommandFollow
• Theresa J. Smith, United States Army Medical Research Institute of Infectious Diseases (USAMRIID)
• Ian Henderson, Emergent Product Development Gaithersburg Inc.
• Michael M. Meagher, University of Nebraska - LincolnFollow

Document Type

Article

Date of this Version

2011

Comments

Published in Protein Expression and Purification, 75, (2011), 177–185

Abstract

A purification process for the manufacture of a recombinant C-terminus heavy chain fragment from botulinum neurotoxin serotype C [rBoNTC(H_c)], a potential vaccine candidate, has been defined and successfully scaled-up. The rBoNTC(H_c) was produced intracellularly in Pichia pastoris X-33 using a three step fermentation process, i.e., glycerol batch phase, a glycerol fed-batch phase to achieve high cell densities, followed by a methanol induction phase. The rBoNTC(H_c) was captured from the soluble protein fraction of cell lysate using hydrophobic charge induction chromatography (HCIC; MEP HyperCel™), and then further purified using a CM 650M ion exchange chromatography step followed by a polishing step using HCIC once again. Method development at the bench scale was achieved using 5–100 mL columns and the process was performed at the pilot scale using 0.6–1.6 L columns in preparation for technology transfer to cGMP manufacturing. The process yielded approximately 2.5 g of rBoNTC(H_c)/kg wet cell - weight (WCW) at the bench scale and 1.6 g rBoNTC(H_c)/kg WCW at the pilot scale. The purified rBoNTC(H_c) was stable for at least 3 months at 5 and -80 °C as determined by reverse phase-HPLC and SDS–PAGE and was stable for 24 months at -80 °C based on mouse potency bioassay. N-Terminal amino acid sequencing confirmed that the N-terminus of the purified rBoNTC(H_c) was intact.