reprogramming and tissue engineering Flashcards
first experiment where reprogramming was possible
1962
nuclei from white frogs into green frogs
SCNT
mechanisms behind resistance of reprogramming
contents of egg are trying to reprogram donor nuelci
epigenetics try to keep cellular identitiy
4 master transcription factors of reprogramming
oct4, sox2, myc, klf4
gold standard pluripotency assay
tetraploid complementation
electrofusion of egg so cells can proliferation, injection of oiPSCS, entire organism is derived from iPSCs
not performed on humans because is unethical
goldstandard in humans is teratoma assay and see if they form all three layers
pioneering TF
oct4 and sox2
they can bind to closed chromatin
steps in iPSC disease modelling in hypertrophic cardiomyopathy
- make proper iPS cells
- make cardiomyocytes
- do they show attributes of disease
why do attributes of cardiomyopathy form after only 40 days instead of 18 years
no hormonal stimulation that could correct disease feedback
stiff environment for iPSC which increases mechanical load (this doesn’t happen until adolescence and blood pressure increases)
calcium cycling could be different
good iPSC model
- monogenic inheritance
- high penetrance (if you have the mutation you have the disease)
- not late age of onset
- want human recapitualation, not mice
- cellular phenotype model in dish
- accessible differentiation, not specialised
BAM cocktail
Ascl1, brn2, myt1l
collagens
self organise
- COL1a1 and COL2A1 for tensile strength, tendons and ligaments
FACIT- bind inbetween
COL4A1, in bm, gives cells orientation, function not for strength
COL10a1- inflamed cartilage
how is collagen involved in migration
fibronection and collagne = no migration
lack of collagens = integrain binding to fibronection and tensin signalling cascade to induce actin myosin contractility
growth factor binding
synergystic = FGF2 and heparin Inhibitory = TGFbeta1
