Thread by @elliotswartz

It's been almost 2 weeks since the historic announcement of FDA's green light for cultivated chicken from @upsidefoods. This coincided with over 100 pages of new information related to the production and safety of #cultivatedmeat.

So what did we learn?

nytimes.com/2022/11/17/cli…

Let's start w/ the conclusion. The FDA "did not identify any properties of the cells as described that would render them different from other animal cells w/ respect to safety for food use."

Cells are cells, whether grown inside or outside the animal

Here's what was evaluated:

Cells: 2 cell lines were used. Myoblasts acquired from an adult chicken & fibroblasts acquired from a mid-stage fertilized egg.

The myoblast line was spontaneously immortalized. The fibroblast line was immortalized through genetic engineering (more on that later)

Serum: Fetal bovine serum (FBS) was used in pre-production stages to initially culture cells after they are acquired from biopsy (expect this to be true for most cases).

UPSIDE also submitted data on production processes with and without serum. Both were deemed safe.

So why include data with serum when the company has previously stated it has developed animal-free media growth media?

fooddive.com/news/upside-fo…

On p. 98 of their submission:

Basically, it is to demonstrate that using serum is no different than conventional meat, which contains residual blood. This reasoning also later supports the use of recombinant growth factors, which are the same proteins found in blood & tissues.

The company also said that production with and without serum helps them understand how media influences the composition of the end product.

So will @upsidefoods use any serum in the product that goes to market? That is for them to answer.

It's also noted that in serum-free processes the company may use bovine serum albumin, a protein purified from serum. They state they are phasing this out in favor of alternative forms, which should be straightforward. Some ways to do so here:

https://twitter.com/elliotswartz/status/1594679989890215936?s=20&t=gZVSGxqnR68fGq3_1wrVUQ

Antibiotics: Antibiotics are used only during initial cell procurement. They're not used at all during production

This is consistent w/ our expectations for the industry. Decoupling meat production from antibiotics is a huge benefit of #cultivatedmeat.

gfi.org/blog/cultivati…

Nutrition: Cultivated chicken (w/ and w/o serum) was compared to two different types of conventional chicken.

FDA notes that nutritional composition is similar but not exactly identical.

Nutrition: Full fatty acid profile and amino acid profile data. Amino acids are particularly similar. Greater variation in fatty acids between samples.

It was noted that cultivated chicken had higher levels of cholesterol, but these are within safe ranges found in other foods.

Nutrition: Vitamin and mineral content of cultivated chicken is also similar to conventional chicken.

Microbial and heavy metal content: Heavy metal content is well below safety thresholds.

Cultivated chicken is a significantly cleaner product, w/ very low bacterial counts. It's also negative for foodborne pathogens like Salmonella (store-bought chicken was positive).

Some other info on the end product:
The product contains no allergens
Shelf life studies will be conducted following USDA grants of inspection
No animal testing was needed to assess safety

Genetic engineering: UPSIDE engineered 1 cell line w/ an endogenous housekeeping gene promoter & chicken TERT to achieve functional immortalization, allowing the cells to replicate indefinitely

The nucleic acid & resulting protein material are identical to conventional chicken

Detractors will claim this is the same as "eating cancer" but it's untrue for various reasons. UPSIDE focuses on the difference between immortalization and transformation, where the former is highly controlled and the latter is unstable.

FDA goes further to conclude that even if cells were transformed, this has no bearing on food safety (read: it won't magically give you cancer).

Simply put, cells don't survive outside a bioreactor, esp. with further cooking and digestive processes. Also applies to proteins.

Another aspect that was assessed relates to unintended effects (of engineered cells or cells generally in culture). FDA agreed w/ UPSIDE's conclusions that animals traditionally consumed as food do not have a latent genetic capacity to produce toxins. Has important implications.

USDA will make the final determination for labels, but this product will probably require a bioengineered disclosure, assuming the engineered cell line is used in production.

Curious if others agree or disagree

ams.usda.gov/resources/indu…

Production process: Includes proliferation as a single cell suspension & a differentiation phase, which occurs as adherent cells in an independent vessel. The cells adhere to the surface, growing in mm thick sheets, which are then harvested and washed.

foodnavigator-usa.com/Article/2022/1…

The differentiation process does not use any scaffolding materials. Other companies have similarly stated they are able to achieve structure by relying on the intrinsic properties of the cells.

https://twitter.com/elliotswartz/status/1466791458749530121?s=20&t=gZVSGxqnR68fGq3_1wrVUQ

This doesn't necessarily mean the resulting products won't contain other ingredients. FDA concluded that foods comprised of or containing cultivated chicken material are safe.

I read this as future "hybrid" products containing cultivated chicken cells would be permissible

What are the next steps?

Before being sold, UPSIDE must obtain a USDA grant of inspection, where the facility will be overseen similarly to other meat & poultry facilities. A HACCP plan must be completed. USDA will also determine labels for packaged products (not restaurants)

The exact timeline for this is uncertain, but it will be faster than the FDA premarket consultation process (which took about 13.5 months total from the date of receiving the full safety dossier)

H1 2023 is a safe bet in my opinion

Other companies are currently under the FDA premarket consultation review process, so additional clearances should be expected in the coming weeks to months.

Having this information public will educate & mobilize other companies and regulatory agencies.

Many see this & say it's not natural. But the conclusion is that consuming cultivated animal cells is as safe as those from a living animal

No different than those who fought against freezers in favor of "natural" ice harvested from lakes. History rhymes
theatlantic.com/national/archi…

What other questions do you have?

Post them in the thread and I will try to answer.

Let me know if I got something wrong.

Sources of information:
fda.gov/media/163261/d…

fda.gov/media/163262/d…