23 Questions with Keerthana Subramanian
23 Questions with Forge is our fast-paced series where our team members are challenged to answer 23 rapid-fire questions about trending topics in gene therapy development.
Forge's downstream process development team streamlines the development timelines for AAV gene therapy products to help our clients reach their milestones faster. Hear from Keerthana Subramanian, Scientist II, on how Forge's data-driven bespoke platform approach builds industry-leading chromatography processes. Watch the full video below!
Read the interview:
Question: Sorry to interrupt. Can we ask you 23 Questions?
Keerthana: Sure! Hi! My name is Keerthana Subramanian, and I am a scientist II in downstream process development here at Forge Biologics.
Question: Let’s jump right in. What is a critical part of downstream processing?
Keerthana: Forge Biologics is leading the industry in developing anion-exchange chromatography and affinity chromatography.
Question: What are some benefits of Forge’s affinity chromatography platform?
Keerthana: It streamlines the development timelines for AAV gene therapy products, and it helps our clients reach their milestones much faster.
Question: How does Forge streamline its platform process?
Keerthana: Data drives our decisions here at Forge. When it comes to optimizing and developing specific unit operations, we either leverage historical data or generate new data to support the platform process.
Question: Can you give me an example?
Keerthana: Sure, let's take a look at affinity chromatography. We have a buffer matrix that can be implemented across resin types and across serotypes. Of course, we can use specific serotypes and evaluate the impact of these different conditions to make data-driven optimizations.
Question: We like to toss in a couple of fun questions. Which superpower would you like to have?
Keerthana: Teleportation! The idea of having my morning coffee in Italy and still make it back to my 9 AM meeting sounds exciting. Would you like a coffee?
Question: Sure! Wow. Look at that view. So, in affinity chromatography development, can we use novel serotypes?
Keerthana: Yes! We have worked with many serotypes here at Forge (including novel serotypes). Because of the team’s vast experience, we have a wide range of knowledge across the board.
Question: What are the key advantages of the purification process?
Keerthana: It is agnostic to all serotypes, except affinity chromatography, because the resin type may change.
Question: How does the purification process contribute to meeting the growing demand for AAV?
Keerthana: As we all know, the AAV gene therapy market is fast growing. Because of this, our clients have very tight timelines to meet their milestones. Forge’s platform purification process helps our clients with just that: producing material quickly to meet their timelines.
Question: Personal question: what is on your phone background?
Keerthana: My sister and I are celebrating her 2nd or 3rd birthday. I’m just about to finish a run in the lab. Can I meet you there? Welcome to the downstream lab, my favorite place at Forge Biologics.
Question: Can you show us some of the features?
Keerthana: Yes, we see a bunch of ӒKTA Avants™ here. In the next aisle, we have a lot of ӒKTA Pure™. On this side of the aisle, we have ӒKTA Pilots™, which supports our large-scale manufacturing in the lab space.
Question: Tell us more about the single-use chromatography systems.
Keerthana: Yes! The in-house single-use chromatography systems are great because they support closed processing, reducing the risk of contamination. At Forge, Repligen ARTeSYN and Cytiva ÄKTA Ready™ 450S support robust single-use chromatography systems at different manufacturing scales.
Question: Which actress would play you in a movie about your life?
Keerthana: Simone Ashley! She plays Kate Sharma in season 2 of Bridgerton. But I wonder if she has time to learn about AAV purification.
Question: How does affinity chromatography impact an empty:full ratio?
Keerthana: Affinity chromatography does not impact empty:full ratio.
Question: How do you manage the challenges related to AAV stability in large-scale affinity chromatography?
Keerthana: We eliminate hold time before affinity chromatography to ensure stability. What this means and how we do it is by continuously processing so there is no break. We also perform stability studies within the lab space to generate data to support any hold times, should they be implemented. We are also looking into alternative techniques to reduce processing times in the purification steps.
Question: Can you explain the concept of resin binding capacity?
Keerthana: Resin binding capacity is essentially the total amount of viral vector we can load onto a resin before we observe a significant breakthrough of the unbound vector. This is one of the most important parameters in AAV vector purification because underloading and overloading a column can cause significant loss to the recovery.
Question: What are other important factors?
Keerthana: There are many important factors. Some examples are residence time, elution buffer pH, elution buffer matrix, and adding any stabilizers to the buffer system. The list goes on. I'm just about wrapped up in the lab. I will see you in the library. It's a more comfortable place to chat.
Question: Great plan! Serious question: If you could only eat one food for the rest of your life, which one would it be?
Keerthana: This is easy. It would be my mom’s idlis (a rice pancake) and onion chutney (which is like a dip).
Question: You’ll have to bring some to share. Can you talk about automated affinity chromatography methods?
Keerthana: I’m a big fan of automated chromatography methods! Automation in general. It removes operator variability, which is key when we are executing processes such as these. Here at Forge Biologics, we have templates for chromatography methods across different scales, so no matter who the operator is, the run is executed the exact same way. We have a template for sanitization and a template for the run itself to ensure consistency between runs.
Question: What are your insights into impurity removal?
Keerthana: One of the goals of downstream processing focuses on product and process-related impurity clearance. For example, affinity chromatography focuses on the removal of host cell protein, and the enrichment step focuses on the removal of empty capsids.
Question: Which TV show always makes you laugh?
Keerthana: It would be Gilmore Girls. I think I'm rewatching it for the 7th time. I’m team Jess. What about you?
Question: I’m supposed to be asking the questions! Also, Team Jess. What considerations go into developing effective wash step conditions?
Keerthana: The goal of a wash step is to reduce contaminant levels and to reduce elution precipitation. It is a key step in the process. When we develop a wash step, we investigate the critical process parameters within the wash step (like pH, buffer matrices, etc.) and understand the impact they have on the overall performance of the process.
Question: You moved from Boston to Columbus. Do you like it here?
Keerthana: I love it here. Columbus has become my home. I think all of you should come visit Forge Biologics. Let me show you!