Cultivated meat has a growing audience - headlines are breaking into the mainstream, and the industry is beginning to attract non-scientists who want to work on food sustainability.
Like any field, cultivated meat has its language, which can be confusing at best, even alienating and restrictive at times, as it can hinder communication. For example, in a 2020 study from The Ohio State University, authors found that the existence of scientific jargon in text resulted in readers becoming discouraged. One reason was that reading language that was specialised made study participants feel like “they don’t belong”. However, having a common language within the industry is extremely important as it can foster collaboration between the players and drive major developments.
To help newcomers to the cultivated meat industry who have yet to become familiar with the jargon, we decided to spare them the time on research, and we've gathered the key terms in one place.
Glossary of terms used to describe cells in cultivated meat
(Cell) Type: normally (but not exclusively) used to inquire or distinguish between cells from different species or tissues, e.g. avian vs. bovine, or muscle vs. fat
Undifferentiated: cells that don't yet have a tissue type
Differentiated: cells that have a specific tissue type
Transdifferentiated: cells that have converted from one developed cell type to another
Lineage committed: a cell that has changed from undifferentiated to being on a developmental path towards a specific cell type
Primary: cells taken directly from living tissue (e.g. biopsy material) for growth in vitro
Pluripotent: cells able to develop ("differentiate") into many types (in terms of tissue, not species...)l;
Multipotent: cells able to develop into more than one cell type, but not all (they're more limited than pluripotent cells); adult stem cells and cord blood stem cells are considered multipotent
Totipotent: cells able to develop into any embryonic and adult cell type
Stem: cells are able to develop into many types (i.e. stem cells are pluripotent)
Embryonic stem: cells taken from a blastocyst (the ball of cells that a fertilised egg cell grows into about a week after conception)
Adult stem: undifferentiated multipotent cells, found throughout different tissues in the body after development, that multiply and replenish dying cells and regenerate damaged tissues
Somatic stem: same as "adult stem"
MSC: Mesenchymal stem cells, multipotent cells that can develop many types, including osteoblasts (bone cells), myocytes (muscle cells) and adipocytes (fat cells)
Satellite: a population of muscle-resident stem cells that are essential for efficient tissue repair
Progenitor: descendants of stem cells that have started to differentiate, typically are multipotent rather than pluripotent, and are on the way to further differentiating into specialised cell types
Precursor: a more differentiated cell than a progenitor cell that is typically multipotent and has lost most (but not all) of its stem cell properties; often used to describe the intermediate cell before it becomes fully differentiated
Induced: typically used to describe "induced pluripotent stem cells" (iPSCs), where "induced" means the cells (typically adult stem cells) have been genetically reprogrammed into an embryonic stem (ES) cell-like state through the forced expression of genes needed to maintain the defining properties of ES cells
Immortalised: cells grown from a primary cell culture (which would normally not replicate through cell division indefinitely) which, due to either spontaneous or targeted mutation, can keep undergoing division
Line: typically (although not exclusively) used equivalently to "immortalised", i.e. a "cell line" is a culture of immortalised cells. Broadly, a cell line is a cell culture selected for uniformity from a cell population taken from a homogeneous tissue source.
Adherent: cells that need to be attached to a surface in order to grow (true of most cell types and primary cell cultures), so growth is constrained by available surface area
Suspension-adapted: cells that can grow without attachment to a surface, so growth is constrained by viable cell density
Myocyte: muscle cell
Myoblast: the precursor of a myocyte
Adipocyte: fat cell
Pre-adipocyte: the precursors of an adipocyte
Fibroblast: a cell that creates connective tissue
Bovine: from a cow
Porcine: from a pig
Ovine: from a sheep
Avian: from a bird (galline is specifically from a chicken, although avian is more commonly used)
Piscine: from a fish
Murine: from a mouse (often comes up because mouse cells have historically been used in cell culture research)
Glossary of terms used to describe media for cultivated meat
Media: a liquid mixture of ingredients, providing cells with a nourishing environment to live in
Culture media: typically used to mean a complete media formulation that combines basal media and a formulation of signalling ingredients, such as serum
Complete media: same as "Culture media"
Growth media: generally the same as "Culture media", although can be specific to "Expansion media" or "Proliferation media"
Expansion media: media used to grow the number of cells, typically aiming for sustained fast growth over multiple cell divisions, with a high density of cells
Proliferation media: same as "Expansion media"
Differentiation media: media that promotes cells to change from one, typically less specialised type, to another, typically more specialised
Starvation media: media depleted in certain ingredients in order to control cell behaviour, often used as part of a differentiation protocol
Basal media: part of a complete growth media formulation, mainly providing the nutrients that cells need: carbohydrates, amino acids, fatty acids, salts and vitamins
Serum: the fluid component of blood, commonly used in traditional cell culture media - as a supplement to basal media - because it contains a complex (undefined) mix of additional nutrients and critically, biologically active molecules that support cell growth
FBS (alternatively FCS): fetal bovine (or calf) serum, the most common type of serum used, sourced from cow fetuses slaughtered with the pregnant mother
Platelet lysate: an alternative to serum as a source of the biologically active molecules that support cell growth; historically sourced mainly from human blood, now being sourced increasingly from cows
Serum-free media: used to describe either a serum-free replacement for FBS or a complete media formulation that doesn't contain any serum
Chemically defined media: a formulation in which all the ingredients are known, often used to indicate that the formulation is serum-free
Animal-component free (ACF) media: a formulation with no animal-sourced ingredients (including sourced from humans) directly included or used in the production process of any included ingredients
Xeno-free: "xeno" means "other" (cf. "xenophobia"), and in media terms, it specifically means free of non-human animal ingredients, so, for example, human platelet lysate is a xeno-free alternative to serum
Media exchange: media in bioreactors typically needs to be exchanged for a fresh formulation because nutrients are depleted while metabolites that limit growth, like lactate and ammonia, accumulate
Conditioned media: media that has had cells growing in it which have released biologically active components that affect the behaviour (e.g. differentiation) of other cells subsequently cultured in the media
Spent media: the residual media after cultured cells have grown or differentiated in it, often analysed during media development for insights into improving the initial formulation (e.g. identifying which nutrients could be added in greater quantity to accelerate cell growth)
Recycled media: media that is re-used, having been removed from cell culture and treated in some way to replenish its nutritional or biological capacity (in order to reduce the total cost and quantity of ingredients for a given amount of biomass produced)
About Multus, the go-to Partner for the Cultivated Meat Industry
At Multus, we believe that having precise, common terminology for cellular agriculture is a crucial part of scaling cultivated meat to ensure we’re all speaking the same language and promote collaboration.
To make cultivated meat the affordable and sustainable choice for everyone, we are tackling the cost of key ingredients and developing new products under food-safe manufacturing standards. `Partnering with Multus can enable cultivated meat companies to scale-up and achieve price parity.
Click here to learn more about the challenges for scaling cultivated meat and how they can be solved https://www.multus.bio/news-and-articles/wild-proteins-raw-materials-and-supply-chains-the-challenges-for-scaling-the-cultivated-meat-industry
Or here if you think we missed an essential term or you have other ideas for improving our glossary https://www.multus.bio/#contact
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