Executive Summary

The AAV-DJ capsid, a hybrid of multiple AAV serotypes, is engineered to achieve broad tropism and high transduction efficiency across a range of cell types both in vitro and in vivo. This makes it a valuable tool for early-stage discovery and preclinical validation. Franklin Biolabs provides expert production of AAV-DJ and other engineered capsids, leveraging the deep institutional knowledge transitioned from the Penn Vector Core. Our process ensures high-purity, high-titer vector preparations suitable for demanding preclinical applications, supporting programs on an 18-24 month timeline to IND.

The Challenge of Species-Specific Transduction

Selecting an appropriate AAV capsid for a therapeutic program requires a nuanced understanding of transduction biology. A vector’s performance in one preclinical model does not guarantee equivalent behavior in another, let alone in human subjects.

Published data highlights these translational gaps. For instance, hepatocyte transduction patterns can show inverse zonation between species, a consideration for liver-directed therapies (PMID: 21778099). The molecular fate of the vector genome itself can also exhibit significant heterogeneity post-transduction, influencing the persistence and level of transgene expression (PMID: 20113166). These variables underscore the need for a data-driven approach to vector selection and preclinical model design.

AAV-DJ: A Hybrid Capsid for Superior Preclinical Utility

The AAV-DJ vector was developed through DNA family shuffling of eight distinct AAV serotypes, followed by selection for vectors that could evade neutralization by intravenous immunoglobulin (IVIG). The resulting capsid exhibits robust transduction across a wide range of tissues.

Key attributes of AAV-DJ include:

• Broad Tropism: Efficiently transduces numerous cell types, making it a versatile tool for initial target validation.

• High In Vitro Efficiency: Outperforms many natural serotypes in cell culture applications, facilitating rapid screening.

• Heparin-Binding Domain: Contains a heparin-binding domain similar to AAV2, which facilitates cell surface attachment.

Our integrated services provide clients with deep expertise across all aspects of vector production and analytics, fostering a collaborative partnership to meet program-specific goals.

Production and Analytics for Engineered Vectors

Manufacturing engineered capsids demands rigorous process control and deep analytical expertise. The team at Franklin Biolabs, which includes key personnel from the former Penn Vector Core, has an established track record of producing complex vectors for academic and industry clients worldwide.

Located in a >100,000 sq ft facility, our research vector production service provides the high-quality material necessary for IND-enabling toxicology studies. While the Franklin Biolabs brand launched in 2024, our scientific team’s work has contributed to a 100% successful IND rate for programs they have supported since 2019.