Stem cells Flashcards
ESCs, iPSCs, mesenchymal
risk of tumour formation and immune rejection
Embryonic Stem Cells: pluripoteent from early stage embryos
Induced Pluripotent Stem Cells: reprogrammed somatic cells to pluripotent from fibroblasts
Mesenchymal (multi-potent) - mesoderm- adipose tissue
ectoderme- neuronal
endoderm - pancreatic islet
stem cell - more risk of tumour formation
differentiated - more risk of immune rejection (secreating cytokines and others that recognise as foreign)
B cells from iPSCs to cure diabetes (cell therapy)
make progenitor immature B cells with special cytokines, chemokines etc
differentiation into lineages
culture them in bioreactors to form granules (insulin)
mature B cells
biomanufacturing
transplanted
Bioprocessing techniques for pancreatic islet
multiplate culture
roller bottle
wave bag bioreactor
Development of iPSCs
isolation of mouse ESCs
dolly
isolation of human ESCs
somatic cell and embryonic stem cell fusion
reprogramming iPSCs (mouse)
reprogramming human fibroblasts
chemical reprogramming in plasmids and viruses
Organs with stem cells and stem cells niches
High regeneration: intestine, skin, bone, bone marrow
Upon injury (dormant): liver, fat, muscle
Lower/specific regeneration: oesophagus, bladder, brain, lungs, stomach
No regeneration: heart, vasculature, kidney
niches:
brain (neuronal)
blood (hematopoietic)
bone (muscular)
ageing in stem cell lineage
quiescent stem cell- not as potent anymore (more silenced), trancriptional heterogeneity
activated stem cell progenitor - abnormal activator (inflamation, cancer)
commited progenitor - bias (makes more of a certain cell type)
ageing in the surrounding niche
secreting wrong inflammatory cytokines or others
immune cell infiltration
niche stiffening and extracellular matrix
production of iPSCs and applications
OSKM transcription factors block regulatory networks, recruit epigenetic regulators (Tet 2), that will demethylate enhancers and promoters and release gene expression networks
fibroblasts- epithelial cells - iPSCs
chemical reprogramming with small molecules
fibroblasts-epithelial cells- Xen like - iPSCs
applications: disease models, generate organoids, tissue regeneration, rejuvenation, cell therapy, embryo models
Rejuvenation and embryo modeling
rejuvenation: partial reprogramming don´t fully recover pluripotency - induce molecular changes, reverse ageing
reprogramming - 2D and 3D: induce 2D culture models through trophoblast stem cells (TSCs) or iPSCs and 3D with blastocyst like models
autologous and allogeneic therapy
autologous: gene correction in iPSCs from patient - differentiate- transplant
allogeneic: start from universal donor (check for lymphocytes blocking) - blood cancer, immune diseases
two major sources of MSCs, injurys - source
perinatal: placenta, umbilical cord, wharton jelly, placental, amnion, chorion membrane, cord blood
adult: bone marrow, adipose tissue, dentalpulp, blood (peripheral and menstrual) other body fluids, muscle
brain and spinal cord injury - bone marrow
reproductive disorders and skin regeneration - adipose tissue
pulmonary disease and ARDS - umbilical cord
Naive and prime
naive - resembles embryo cell mass (pre implantation) - special media to stop from going to the prime state (through trophoblast or hypoblast lineage)
prime- extract epiblast (post implantation) - a little advanced in differentiation path
X chr re-activation and problem
in prime state females have one inactive X to balance active gene expression between sexes (post implatation) so when you chemical reprogram you activate the X again
erosion of human chromossome causes major remodelling: things which are not expressed become expressed so the transcriptome/proteome becomes messed up because of erosion - find ways to maintain X chr inactivated
solution: reprogramme cells into naive and start capacitating them in culture (differentiating) and make primed cells now expressing again the RNA
blastoid formation stages
B3-B6 (before implantation)
b3 naive cells
gene regulation - blastocyst - questions and solutions
interplay of epigenetic marks? multiomics approach
epigenetic regulation of EGA entrylexit? epigenetic editing
effect of cell polaritylposition on epigenome? spatial epigenetics
contribution to lineage decision plasticity? SC based embryo
post implantation epigenetic profiles? improved embryo culture
