AAV Vector Manufacturing
BlogJune 20, 2021

Adeno-associated viruses (AAV) are small viruses that can infect humans and other primate species. The particularity about AAV is that it’s altered from a naturally occurring virus into a mechanism to modify faulty, corrupted, or missing genes. AAV gene therapy is one of the most promising advances in modern medicine due to its therapeutic impact on a wide range of diseases and disorders.

What are AAV vectors used for?

AAV vectors are used as a delivery mechanism in gene therapy to alter cells that are causing a disease or disorder. One of the reasons why AAV is so successful in gene therapy is because it doesn’t develop into a disease that will negatively impact human health as other viruses do. AAV cannot replicate in the body without external help which enables healthcare professionals to accurately control the quantity and manner in which AAV will be administered.

How does an AAV vector work?

Due to AAV being a non-enveloped virus, it can be engineered to deliver DNA to target cells. The viral components are replaced with new DNA in the naturally occurring virus by using AAV single strand genetic material that is suitable to edit. Researchers use simple splicing techniques to remove the inner section of AAV and use the ends that are fundamental for gene delivery. The inside portion is then replaced with a new healthy gene, this modified single strand DNA is now an AAV vehicle that will transmit its genetic material to target cells. This then becomes a coded vector employed to deliver healthy copies of genes to designated tissues or organs and modify faulty, corrupted, or missing genetic material.

What does AAV mean in gene therapy?

AAV is one of the most meaningful advancements in gene therapy. Having the possibility to deliver new healthy material to faulty DNA means rare and severe diseases can become treatable and in many cases completely cured. AAV vectors give hope to patients with genetic disorders and cancer. In the coming years, AAV-based treatments will be able to cure conditions like hemophilia and spinal muscular atrophy among many others. Not only is AAV an efficient method to deliver healthy DNA to target cells, but it’s also much quicker to develop which is why nearly half of gene therapy products being developed today are using it. Compared to conventional drug development, the development time for viral-vector based therapies is much shorter.

How are AAV vectors produced?

To clone the vector, scientists need another virus to grow the AAV virus, this is known as a helper virus. The helper virus helps unlock the potential of AAV. Then, both AAV and the helper virus are combined with separate bacteriums which result in the creation of plasmids. As soon as these plasmids are available, scientists insert both the AAV and helper virus plasmids into a mammalian cell for replication. Once those two elements are inserted, mammalian producer cell lines essentially become a factory to produce more AAV vectors.

How are AAV plasmids produced?

Plasmids are a key element in developing an efficient AAV vector for gene therapy. To produce these plasmids, bacterial cells are cultured in an optimized growth environment. Here, nutrients are fed using fermentation. Then, using centrifugation microbial cells are harvested. Once this step is done, cultured host cells are disrupted using alkaline lysis to release the intercellular plasmids. Next, AAV plasmids are purified using chromatographic methods. Lastly, plasmids are analyzed to ensure they meet the necessary quality standards and are a reliable product.

With over 20 years of experience in plasmid manufacturing, Andelyn Biosciences produces batches of plasmids to client specifications. All products are created following best practices for plasmid production and have full traceability as well as document control that ensures client specifications are rigorously met. By partnering with Andelyn Biosciences you ensure the availability of plasmids will not slow down your AAV project.

Contact Andelyn Biosciences to easily source quality plasmid development and manufacturing to your specifications.