stem cells and regenerative medicine Flashcards
what are stem cells
differentiate into many diff cell types
capable of self renewal via cell division
provide new cells as organism grows and replace cells that are damaged or lost
several diff types of stem cells, embryonic adult and induced pluripotent stem cells
targeted by researchers for their therapeutic potential
uses of stem cells in disease/injury
blindness wound healing spinal cord injury cancers myocardial infarction
what are stem cell sources
iPSC = induced pluripotent cells
ESCs = embryonic stem cells
ESCs = adult stem cells
used for:
- model for basic and translational studies
- cell replacement therapy
- cell differentiation
- disease modelling
- 3D organoid models
- drug screening
- developmental biology
comparison of stem cell types
- tissue specific stem cells are maintained in special supportive microenvironment called = STEM CELL niches
- supporting ECM
- neighbouring niche cells
- secreted soluble signalling factors
- physical parameters, shear stress, tissue stiffness, and topography
- environmental signals (metabolites, hypoxia, inflammation )
describe embryonic stem cells
pluripotent = unlimited growth potential
higher risk of tumour creation
risk of being genetically different from recipients cells, higher risk of rejection
unlimited number of cells due to high cell potency
very low probability o mutation-induced damage in DNA
describe adult stem cells
oligopotent - unipotent = limited cell potency
less risk of tumour creation
compatible with recipients cells, low risk of rejection
limited numbers may be obtained
higher probability of mutation induced damage in the DNA - risk of disease
describe induced pluripotent stem cells
less growth potential that embryonic stem cells
less risk of tumour formation
compatible with recpitients cells = low risk of rejection
rather limited numbers may be obtained
higher probability of mutation induced damage in DNA = risk of disease
pluripotent factors (OSKM)
c-Myc promotes DNA replication and relaxes chromatin structure, allows oct3/4 to access target genes
sox2 and klf4 co-operate with oct3/4 to activate target genes
these encode TFs which establish pluripotent transcription factor network
result in activation of epigenetic processes that establish pluripotent epigenome
the iPS cells have a similar global gene expression profile to that of ES cells
Describe stem cell tracking
cell therapy
imaging to track cell therapies
in vivo imaging can aid developmental and clinical translation of cell-based therapeutics using non-invasive in vivo long term cell tracking in the preclinical settings