Modeling electrostatic interactions of baculovirus vectors for ion-exchange process development

Area of Science:

• Biotechnology
• Bioprocessing
• Gene Therapy Manufacturing

Background:

• Product-related impurities are a significant challenge in recombinant viral vector production for gene therapy and vaccination.
• These impurities can negatively impact biological efficacy, process yield, and overall productivity.
• Ion-exchange chromatography is a common purification method for viral vectors, making electrostatic behavior analysis crucial for impurity removal.

Purpose of the Study:

• To investigate the electrostatic properties of infective viral particles and related impurities.
• To develop a predictive model for optimizing ion-exchange chromatography in viral vector purification.
• To enhance the understanding of how viral components influence electrostatic interactions during purification.

Main Methods:

• Recombinant baculovirus used as an enveloped virus model.
• Isolation of infective viral particles and product-derived impurities (dsDNA-, glycoprotein-, envelope-deprived particles).
• Zeta potential analysis via dynamic light scattering and calculation of electrostatic interaction energy profiles.

Main Results:

• Distinct zeta potentials were identified for infective viral particles and major virus-related impurities.
• A model was developed based on critical viral components influencing electrostatic properties.
• The study provides a deterministic tool to differentiate viral particles from impurities based on electrostatics.

Conclusions:

• Understanding electrostatic behavior is key to improving impurity removal in viral vector purification.
• The developed model aids in optimizing ion-exchange chromatography for viral vectors.
• This knowledge facilitates early-stage process development by predicting optimal selectivity conditions.