L.20 Modelling Development in Vitro Flashcards
L.O
- Classify the three main stem cell types and where they are derived from
- Describe how stem cells can be used to study development in vitro
- Outline the techniques used to identify cell identity
Somatic Cells
- Body cells
- Highly specialised
- Terminally differenciated cells
- Limited ability to replicate
DNA
- Genetic instructions
- All somatic cells have some geneitic code, but genes turned on specialise the cell
DNA → RNA → Protein
Stem cells
- Undifferentiated and unspecialised
Have particular potency:
- Ability to differentiate into a soecific cell type (totipotent, pluripotent, multipotent, terminally differentiated)
- Self renewing, make exact copies of themselves
Totipotent
Pluripotent
Multipotent
Terminally differentiated
Totipotent = any
Pluripotent = many
Multipotent = restricted
Terminally differentiated = none
3 Main types of stem cells
- Embryonic stem cells
- Adult stem cells
- Induced pluripotent stem cells
Embryonic stem cells
- Derived from inner cell mass of blastocyst
- Plutipotent cell type
Adult stem cells
- Dertived from developed organs
- Multipotent: lineage restricted (neural, blood, stomach etc.)
Induced Plutipotent stem cells
- Somatic cells ‘reverted’ backwards to pluripotent embryonic stem cell-like cells by genetic reprogramming
Embryonic stem cell processing
- Taken out of ICM and cultured
- Certain factors can then be added, changing the env. to make them highly specialised and terminally differentiated
- Helps with understanding how cells develop
Adult stem cell processes
eg. blood cells
- Taken from bone marrow
- cultured
- Depending on conditions and env. in the culture will depict the specialisation
- Can become WBC, platelets, RBC
induced Plutipotent stem cell processes
eg. skin
- Cell taken out and cultured
- Genetic reprogrammed to form pluripotent cells
- Can choose which cell type we want it to become
Stem cells used for…
- Understanding development
- Understand disease
- Drug design anf drug screenign
Growth factors
- A molecule capable of stimulating differentiation and proliferation
- Allow scientists to differentiate stem cells study by behaviour
e.g Growth factor A added to stem cells may cause them to proliferate lots
Growth factor B may stimulate apoptosis, migration etc.
How do we know we have the right cells?
- Looking at phenotype
- Looking at molecular markers
Cells have molecular identities:
- Gene expression
- Protein expression
- microRNA
- Epigenetics
