Stem Cells Flashcards
What is a stem cell
A cell that has the ability to continuously divide and differentiate (develop) into various other kind(s) of cells/tissues
What are totipotent stem cells?
Each cell can develop into a
new individual cell
What are pluripotent stem cells?
Cells can form any cell type
(over 200)
What are multipotent stem cells?
Cells differentiated, but can
form a number of other tissues (e.g adult stem cells, cord blood)
What are unipotent stem cells
stem cells that are fully differentiated and can therefore only give rise to cells with identical phenotypic characteristics
what is the stem cell niche
area of the tissue in which stem cells reside in a dormant/ quiescent state
What are some ways a cell may receive signalling
Humoral, Neural, Mechanical/Structural
What are some examples of humoral signalling
Nutrients and growth factors coming from the blood
What are some examples of neural signalling?
Signals that come from surrounding tissues
What does stimuli influence in a stem cell?
- Maintenance of quiescence
- Self-renewal
- Differentiation
What are some examples of structural/mechanical signalling?
Adhesion or interaction with the extracellular membrane
Where are some locations of stem cell niches?
Bone marrow
Skin
Central nervous system
Gut
Muscle
Where is the stem cell niche located in the bone marrow?
In the osteoblastic lining cells
Where are the stem cell niches located in the skin?
In bulges of hair follicle between the dermis and epidermis
What are two branches of stem cell niche in neuronal cells
Subventricular Zone and Subgradular Zone
where is the stem cell niches in the gut
found in the crypt of the gut epithelium
Where are satellite cells located in the muscle?
between the basal lamina and sarcolemma
Where can satellite cells be found in the cell cycle?
G0, they can then express a unique expression pattern which changes with the restart of the cell cycle
What occurs when satellite cells are stimulated?
They can differentiate into different muscle precursors-myoblasts and they then differentiate into myofibers
How do myofibers help repair the muscle?
Try and repair the muscle, calcium is released along with HGF
What do you need to try and limit when fibres are damaged?
The release of Nitrous Oxide or any ROS
Main points surrounding Embryonic stem cells
Derived from donated IVF embryos
* Can be grown indefinitely in the laboratory in an
unspecialised state
* Retain ability to specialise into many different
tissue types – know as pluripotent
* Can restore function in animal models following
transplantation
Induced Pluripotent stem cells
Can be grown indefinitely in an undifferentiated state, have similar properties to embryonic stem cells, can be taken directly from patients for research
How can we use stem cells in agriculture?
Reproducing the best breed
* Disease resistant
* Suitability to climate
* Quality body type
* Fertility
* Market preference
