App Note: High-throughput, automated analysis of viral vector titer and process-related impurities

Adeno-associated virus (AAV) based vectors have become the go-to vehicle for systemic delivery of gene therapies. Vector production is, however, an expensive and complex process that results in a small volume of highly valuable product yet sample analysis during bioprocess steps can consume up to one-half of a production batch. Analysis can also require extensive laboratory resources, especially where traditional immunoassays such as plate-based ELISAs are employed.

To explore a solution to these challenges, we investigated analyzing viral vector titer and impurities in a continuous 5-CD run using the Gyrolab^® xPand platform and a combination of Gyrolab kits and assay protocols. Two AAV serotypes (AAV2 and AAV9) plus 3 impurities (host-cell proteins [HCPs], endonuclease, and transferrin) were analyzed for each serotype on one instrument.

The ability to automate and miniaturize five unique immunoassays for two AAV serotypes on one instrument in one run of under 6 hours represents significant hands-on time and sample volume savings compared to manual ELISA or other plate-based methods.