Induced pluripotent stem cells
Induced pluripotent stem cells (iPSCs) are a pluripotent stem cell line that is produced directly from a somatic cell. The technology is based on the principle that somatic cells can be converted in to pluripotent stem ells, by the introduction of four specific genes coding for transcription factors (MyC, Oct3/4, Sox2 and Klf4) (Tahahashi and Yamanaka, 2006).
Applications of iPSCs
iPSCs holds great promise in regenerative medicine, due to the its potential to proliferate indefinitely and give rise to every other cell type in the body such as neurons, heart, pancreatic and liver cells, thus being a single source of cells that could be used in cell therapies, tissue engineering and drug discovery. These applications require large amount of cells of high quality in an efficient, defined and modifiable platform. To this end 3D cell culture systems have developed to produce high quality cells that can be used in high throughput pharmacology and toxicology screening (Yuguo and Shaffer, 2013).
3D cultures of iPSCs
3D cell cultures of iPSCs encapsulates both cell-cell and cell-matrix interactions particulary in studying the differentiation of cells. Most commonly iPSCs can be cultured with and without scaffolds, to generate cells with in-vivo like morphology. Spheroid cultures of iPSCs can used cultured using cell repellant-coated plates, to generate uniform spheroids in a relatively short period of time. These cell cultures are also viable for longer periods with in use of scaffolds such as hydrogels, thus making it possible to create disease models where progressive changes can be observed, such as in neurodegenerative diseases (Haishuang et al, 2013). In addition this method of culturing in 3D and subsequent disease modeling, enables to map both acute and chronic effects of drug exposure.
References
- Takahashi K, Yamanaka S (2006). “Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors”. Cell. 126 (4): 663–76.
- Yuguo Lei, David V. Schaffer (2013). “3D culture system for human pluripotent stem cells” Proceedings of the National Academy of Sciences Dec 2013, 110 (52) E5039-E5048
- Haishuang Lin, Qiang Li, and Yuguo Lei (2017. “Three-dimensional tissues using human pluripotent stem cell spheroids as biofabrication building blocks”. Biofabrication 9 025007