A Quick, Affordable Test for AAVs
This story is part of a series called Supporting Scientists, in which we explore the different ways scientists in academia, biotech, and pharma are using our products to overcome challenges in the field of gene therapy.
Elissa Hudspeth was setting up a manufacturing process for adeno-associated viruses (AAVs) when an ELISA test revealed some disappointing results. Despite her best efforts, the harvest material she was working with contained a low titer of AAVs.
As the assistant director of downstream processing at the Biomanufacturing Training and Education Center at North Carolina State University, Elissa knows that this kind of outcome is just par for the course when developing a process. But after waiting a day for the ELISA results, she started to wonder if there wasn’t a better test she could use at that stage.
“I was thinking it would be good to have a quick check to make sure that there's AAV in our harvest material and if there is, that there’s enough that it's worth us processing further,” she said.
“Also, the baculovirus Sf9 material that we use precipitates some if you store it. So, it's better if we process it fresh.”
Elissa's Experience with the Dip’n’Check Test
Shortly after, when a colleague mentioned that PROGEN produced a lateral flow test for AAVs, Elissa was intrigued. She already appreciated the benefits of lateral flow tests – quick covid tests are an example – but it wasn’t until she happened upon the PROGEN booth at the annual meeting of the American Society of Gene + Cell Therapy in Baltimore, Maryland, that she found out more about the Dip’n’Check test and decided to try it out.
“The first time we used it, we got excited,” she said.
“We did a bunch of tests because they’re fairly quick, easy to do, and affordable. We could test after every step of processing to make sure there were still some AAVs there.”
Since then, Elissa has added the Dip’n’Check test into her toolbox, appreciating that it gives her insights quickly, which enables her to process the baculovirus Sf9 material she uses fresh. In addition, unlike other tests that require the material to be clarified before use, the Dip’n’Check can be used even before clarification, saving her even more time.
Fast Feedback That Goes Beyond the Lab
She also relies on the test to help her gauge the optimal parameters for affinity chromatography. Although the Dip’n’Check is only semi-quantitative, knowing whether the number of fully assembled AAV capsids she’s working with is close to one million, ten million, or a hundred million enables her to not only select the best size affinity column but also to identify how much and how fast to load.
Overall, she is glad to have discovered this test and plans to expand how she uses it.
“We’re also thinking of ways that we could potentially use it in teaching so students could actually see the results of what they're doing,” she said. “Aside from that, it’s been really useful for me and my team, as well as the people upstream from me. Now, when my boss checks in with me, I can tell him that the titer was good the same day that we process it.”
Elissa teaches a 3-day, hands-on course called AAV Quality Attributes: Theory and Practice at North Carolina State University. It is a great learning experience for those who are new to the field and for those who are looking to broaden their expertise with fundamentals and concepts, industry applications, and emerging technologies.
Interested in learning more about AAVs?
The Road to Transforming Medicine Through AAVs
AAV continues to lead the way in gene therapy research. Discover its evolution since the 1960s and its growing role in transforming treatments for both rare and common diseases.
