Removal of transmissible spongiform encephalopathy prion from large volumes of cell culture media supplemented with fetal bovine serum by using hollow fiber anion-exchange membrane chromatography.

Tiffany Avory,Thierry Burnouf,Noriyuki Nishida,Andy Bailey,Ming Li Chou,Junji Tanimoto

doi:10.1371/journal.pone.0122300

Tiffany Avory, Thierry Burnouf

Open Access

https://doi.org/10.1371/journal.pone.0122300

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Journal: PloS one	Publication Date: Apr 13, 2015
Citations: 36	License type: CC BY 4.0

Affiliation: Taipei Medical University, Asahi Kasei (Japan)

Abstract

Cases of variant Creutzfeldt-Jakob disease in people who had consumed contaminated meat products from cattle with bovine spongiform encephalopathy emphasize the need for measures aimed at preventing the transmission of the pathogenic prion protein (PrPSc) from materials derived from cattle. Highly stringent scrutiny is required for fetal bovine serum (FBS), a growth-medium supplement used in the production of parenteral vaccines and therapeutic recombinant proteins and in the ex vivo expansion of stem cells for transplantation. One such approach is the implementation of manufacturing steps dedicated to removing PrPSc from materials containing FBS. We evaluated the use of the QyuSpeed D (QSD) adsorbent hollow-fiber anion-exchange chromatographic column (Asahi Kasei Medical, Tokyo, Japan) for the removal of PrPSc from cell culture media supplemented with FBS. We first established that QSD filtration had no adverse effect on the chemical composition of various types of culture media supplemented with 10% FBS or the growth and viability characteristics of human embryonic kidney (HEK293) cells, baby hamster kidney (BHK-21) cells, African green monkey kidney (Vero) cells, and Chinese hamster ovary (CHO-k1) cells propagated in the various culture-medium filtrates. We used a 0.6-mL QSD column for removing PrPSc from up to 1000 mL of Dulbecco’s modified Eagle’s medium containing 10% FBS previously spiked with the 263K strain of hamster-adapted scrapie. The Western blot analysis, validated alongside an infectivity assay, revealed that the level of PrPSc in the initial 200mL flow-through was reduced by 2.5 to > 3 log10, compared with that of the starting material. These results indicate that QSD filtration removes PrPSc from cell culture media containing 10% FBS, and demonstrate the ease with which QSD filtration can be implemented in at industrial-scale to improve the safety of vaccines, therapeutic recombinant proteins, and ex vivo expanded stem cells produced using growth media supplemented with FBS.

Highlights

Pathogenic prions are protein particles composed of the misfolded isoform of a naturally occurring nonpathogenic cellular glycoprotein, known as the prion protein (PrPC)
One liter of growth medium supplemented with 10% fetal bovine serum (FBS) was passed through a 0.2 μm filter (Thermo Fisher Scientific, Waltham, MA, USA) before being passed through the QyuSpeed D (QSD) column
We observed the adsorption of FBS proteins on the QSD column, most of which had molecular weights of approximately 130 and 40 kDa

Summary

Introduction

Pathogenic prions are protein particles composed of the misfolded isoform of a naturally occurring nonpathogenic cellular glycoprotein, known as the prion protein (PrPC). The misfolded prion protein (PrPSc) causes prion disease. Fatal neurodegenerative disorders classified as transmissible spongiform encephalopathies (TSEs). Prion diseases affect both humans and animals. Several forms of TSE have been identified, including Creutzfeldt-Jakob disease (CJD), kuru, Gerstmann-SträusslerScheinker syndrome, and fatal familial insomnia [1]. The most notable TSE is bovine spongiform encephalopathy (BSE)

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