Leprechaun leads you to lentivirus gold

Monitoring lentivirus titer, structural stability, and non-viral contaminants throughout production is critical to generating the highest yield and highest purity drug product. Most current methods can only work with the purest samples and do not check viral structure, making it impossible to get an accurate viral titer immune to fragmented or damaged viral particles and contaminants.

In this exclusive webinar, now available on demand, meet Leprechaun, the tool that provides five critical pieces of information about crude or pure lentivirus samples. Leprechaun sizes particles to sort out individual lentiviruses from aggregates and uses fluorescent antibodies to confirm if VSVG is where it should be, how many lentiviruses have a capsid, if there is contamination from soluble p24, and if extracellular vesicles (EVs) are present. By using Leprechaun, you can have information on lentivirus composition throughout your entire process.

Watch this on-demand webinar to see how Leprechaun can reveal the secrets of your lentivirus. Alex Shephard, Leprechaun Product Manager from Unchained Labs, explains how the Leprechaun Luni consumable stops soluble p24 from interfering with titer, gives you confidence you’re only counting what you care about, and monitors non-viral contaminants with ease.

Find highlights from the live Q&A session below or register to watch the webinar at any time that suits you>>

You showed the linear range of the viral titer. What are the linear ranges of other outputs? For example, soluble p24?

AS: In terms of the other particle types that we're counting, the linear range of, for instance, the viral aggregates and the EV contaminants is the same as the viral titer. So that is 5 x 106 to 5 x 108 particles/mL. The soluble p24 range is from 5 pg/mL to 10,000 pg/mL.

Can lentivirus pseudotypes other than VSVG be analyzed on Leprechaun?

AS: The lentivirus kit that we've discussed today has been optimized and validated for VSVG pseudotypes. If you're working with a different pseudotype, there is potential to look at it on Leprechaun. My suggestion would be to get in contact with Unchained Labs, and we can have a conversation about your specific application and see if that's compatible with Leprechaun.

How does EV counting work given that lenti particles are also likely to include tetraspanin? Is this a subtraction of VSVG-captured particle count from tetraspanin-captured particle count?

AS: Our viral titer comes from our VSVG capture spots, so as you say, the virus probably will have tetraspanins present on its surface. We get our EV count from our tetraspanin capture spots, which is a separate set of spots from our VSVG capture. What we see in the particles that are captured on the tetraspanin spot is that there is a very low expression of VSVG on these particles. There can be some VSVG, but it's significantly less than is present on the particles captured on the VSVG spot. So based off our data, I think it’s really to do with the amount of the VSVG and tetraspanins they have on their membrane. The viral particles are greatly enriched for VSVG due to their biogenesis pathway compared to the exosome EV biogenesis pathway. So, if we look at the particles that are on the tetraspanin spot, they have a lot lower expression of VSVG, and they're also significantly smaller. Our sizing for particles based on that spot is sub 15 nanometers, which is very small for a lentiviral particle as well. So, by combining the lack of VSVG standing or tetraspanin capture particles, and the small sizing of those particles, we are confident in defining those as not being viral and being EVs instead.

Is there a way to automate the sample and Luni prep?

AS: Yes, there is. The Leprechaun comes with the Luni washer, which has been specifically designed to handle and help automate the processing of Lunis. So, this performs the washing and preparation steps for you, so you can prep up to 24 Lunis simultaneously.

Learn more about Leprechaun: Watch this webinar on demand here>>

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