Purification and functional characterization of gag-spike virus-like particles: Process optimization for efficient...

Area of Science:

• Biotechnology
• Vaccine Development
• Protein Engineering

Background:

• Virus-like particles (VLPs) displaying the SARS-CoV-2 Spike protein are a promising vaccine platform.
• Efficient and scalable purification is crucial for VLP-based vaccine production.

Purpose of the Study:

• To develop and optimize a scalable downstream purification process for Gag-Spike VLPs.
• To ensure the structural integrity and functional immunogenicity of purified VLPs.

Main Methods:

• Optimization of tangential flow filtration (TFF) parameters (TMP, shear rates).
• Evaluation of various chromatographic resins (e.g., SepFast DUO, CaptoCore, CIMmultus QA, HiTrap Q).
• Sequential purification strategies and sterile filtration.

Main Results:

• Maximized permeate flux during TFF while maintaining VLP integrity.
• Identified effective chromatographic methods for impurity removal (host cell proteins, DNA).
• Confirmed VLP purity, size homogeneity, and retention of functional Spike proteins via SDS-PAGE, DLS, and flow-virometry.

Conclusions:

• A robust and scalable purification strategy for Gag-Spike VLPs was established.
• The process preserves VLP structural and functional properties essential for vaccine development.
• This methodology supports the advancement of VLP-based vaccines against SARS-CoV-2.