A Rapid, High-Throughput Assay for Analyzing AAV Empty/Full Capsid Ratio in Process Development for Gene Therapy
Adeno associated virus (AAV) is a leading modality for in vivo gene delivery. Full capsids containing the gene cargo deliver therapeutics to target cells. The presence of empty capsids in the AAV drug product can however compromise therapeutic efficacy hence these need to be detected at different stages of the AAV production cycle. Conventional methods for determining AAV empty/full (E/F) ratio are time-consuming, labor-intensive, and/or require extensive optimization.
Still Analyzing AAV Empty/Full Ratio the Hard Way?
Consider a novel, rapid, and high-throughput method for determining AAV E/F ratio using Octet® Biolayer Interferometry (BLI) in conjunction with Octet® AAVX Biosensors. This innovative technique analyzes intact viral capsids and is ideal for screening both crude and purified samples, facilitating a faster more efficient workflow.
By leverages the high precision and consistency of AAVX biosensors, the assay is ideal for screening in the upstream and downstream bioprocessing stages of AAV development and manufacturing. The method involves the saturation of the biosensor surface with AAV particles, effectively normalizing capsid titer between samples. Consequently, a single measurement suffices to determine the E/F ratio, thereby eliminating compounded errors inherent in other methods.
- Document type: Technical Note
- Last updated: August 2024
- Page count: 16
- Read time: 28 minutes
Enhance Your AAV E/F Ratio Workflow
- Suitable for analysis of crude and purified AAV samples
- No sample purification or enzymatic digestion required (analyzes intact viral capsids)
- Compatible with multiple AAV serotypes
- Efficient: complete assay in as little as 30 minutes
- Cost-effective: AAVX biosensors can be regenerated and re-used multiple times
- Leverages the high precision and consistency of Octet® AAVX Biosensors
- Ideal for screening applications in upstream and downstream process development
AAV E/F Calculator
A useful tool that will help you calculate the required concentration and volume of the empty and full reference samples needed to prepare standards with different percent full ratios.
*Requires Windows® Operating System, version 10 or above.
Illustration of the Octet® BLI AAV Empty/Full Ratio Workflow
Figure 1. (A) the AAVX biosensor is dipped into an AAV sample (Empty or Full). (B) Example of binding response signal of Full (yellow) and Empty capsids (black) normalized to identical capsid titer (N = 2).