Purification and concentration of model viruses using single-pass tangential flow filtration

Area of Science:

• Biotechnology and Bioprocessing
• Viral Vector Manufacturing
• Downstream Processing

Background:

• The vaccine and viral vector industry requires efficient harvest and purification methods.
• Continuous membrane-based operations offer potential improvements over traditional batch processes.
• Model viruses (porcine parvovirus and Suid herpesvirus) were used due to their relevance to gene therapy vectors.

Purpose of the Study:

• To explore continuous membrane filtration techniques for improved viral vector purification.
• To evaluate normal flow filtration (NFF) and single pass tangential flow filtration (SPTFF) for virus concentration.
• To optimize SPTFF conditions for concentrating model viruses and assess protein/DNA removal.

Main Methods:

• Screening of hollow fiber membranes with varying molecular weight cut-offs (100 and 300 kDa) for SPTFF.
• Conducting SPTFF runs with model viruses (porcine parvovirus and Suid herpesvirus) under different conditions.
• Evaluating NFF filter selection and performance, including cleaning protocols for hollow fiber membranes.

Main Results:

• SPTFF did not concentrate porcine parvovirus (PPV) effectively and showed limited protein/DNA removal.
• Optimal SPTFF conditions for Suid herpesvirus (SuHV) involved specific hollow fiber membranes at 10 mL/min and 2 psi.
• SuHV SPTFF achieved approximately 100-fold titer concentration with 37% protein and 32% DNA removal, outperforming batch TFF.

Conclusions:

• Single pass tangential flow filtration (SPTFF) shows potential for concentrating enveloped viruses like SuHV.
• Process parameters such as flow rate and transmembrane pressure significantly influence SPTFF efficiency.
• Further integration of NFF and SPTFF into continuous purification workflows can reduce costs and increase throughput for viral vector production.