Thread by @NewHarvestOrg

Hi again, I'm back (@tobiasmess) to live-tweet for New Harvest about today's #CAOS2020 session which features my wonderful colleague Lea Melzener (from @mosa_meat) about how to get from a tiny 🐮 biopsy to huge amounts of #culturedbeef!
Join here in 10min: caos.community/live

2/n Lea is only in her 2nd year of her PhD in the Stemness&Isolation Team at @mosa_meat and is already about to submit her first paper (comparing different cattle breeds) AND her first review (about donor selection & biopsy regulation), shamelessly making us other PhDs look bad.

3/n Today's talk will give a very practical perspective by covering the following topics: Donor selection, biopsy methodology, economic considerations and EU regulations of #culturedmeat.
...Aaand there's even some exclusive insights into preliminary data about breed selection!

4/n Lea focusses on various kinds of adult stem cells (both muscle derived and adipose derived) but today, she will only focus on Satellite Cells and on making muscle.

5/n Usually, when people talk about the process of #culturedmeat, they start with the cell isolation & proliferation. However, we have to start one step earlier: How do different donor characteristics define the quality and amount of the final product?

6/n There are different very relevant factors that influence Satellite Cell 'quality' (in terms of proliferation capacity, differentiation potential, etc.) such as sex, age, biopsy location at the animal, breed, and many more!

7/n Age: The younger the animal, the higher the growth rate of the isolated satellite cells.
Biopsy location: Chuck contains more type 1, fast-twitch white muscle fibers while hindleg has more type 2 (slow-twitch) muscle fibers.
Breeds: We will get to this later again!

8/n Now let's talk actual biopsy: After you comfortably fixate the animal (without causing any stress to the it!), you can take a biopsy either using a needle (only up to 500mg) or a small incision. After taking the sample, the animal can just jump around on the grass again :)

9/n Economic considerations: The most important factor that determines how much meat you can produce from a single biopsy is the number of doubling of the Satellite Cell. With 50 population doublings, you could produce 10^9> kg of #culturedmeat from a single biopsy!

10/n With 35 population doublings (PDs), you could replace the slaughter of 20 cows from a single biopsy (so if you would take 20 biopsies in one fixation, you could already save 400 animals). With 50 PDs, it would already be 13 Million animals. Wooah, the power of exponentials!

11/n Case study Maastricht: With 35PDs, only 20 cows would satisfy the demand of beef in the(as opposed to 8000 slaughtered animals per year). With 50PDs, only 1 individual would suffice.(We should probably keep two though, we wouldn't want it to get lonely - oh also inbreeding.)

12/n Now let's speak Regulation. There are several relevant regulatory factors, including the Novel food regulation and GMO policies, product labelling and animal inspection. Lea focusses on the latter now:

13/n First, the process of #culturedmeat inspection will have an ante-biopsy inspection of the animal to exclude health hazards by the veterinary who takes the biopsy. Next, both post-biopsy tissue and post-isolation stem cells can be following.

14/n Then there will be a post-production quality and safety assessment (as in traditional meat), making #culturedmeat just as (if not even more) safe than conventional meat production.

15/n We now dive into Lea's exclusive data about the Satellite Cell (SC) quality coming from the different breeds (Belgian Blue, Simmental and Holstein Fresian), comparing SC percentage during FACS sorting, growth rate, differentiation potential.

16/n The inter-breed variation in stem cell proportion is lower than the intra-breed variation, so not too big differences here! The same is true for growth rate & differentiation potential: SCs from all breeds seem to be happy in Lea's culture media.

I hope you're not just tuning in now but if you do, well; here's the summary of Lea's amazing talk.

In future, she will extend her study by comparing even more breeds, different ages, biopsy locations, sexes and more! We are very much looking forward to it :)

Over and out, from @tobiasmess.
Thanks for following @CellAgOS and if you haven't yet, join our #CAOS2020 community at caos.community/slack.

Our next talk will be on Tuesday, 23.06.2020, as always at 9am PT / 6pm CET!