저희는 GABAergic differentiation는 아니지만, ESC나 iPSC 유래의 Dopamine neuron으로는 분화는 많이 진행하고 있습니다. 그동안 하나의 팁을 알려드리자면 얼마나 좋은 상태의 NSC를 얻는 것이 가장 핵심포인트라고 말씀드릴 수 있습니다. 그리고 neuron으로 분화시키면서 maturation 과정에서 많은 세포가 죽는데 세포의 density를 조절하시고 특히 mycoplama에 감염된 세포의 경우 분화가 잘 되지 않으니 유의하시기 바랍니다.

Stem Cells Int. 2015; 2015: 105172.
Published online 2015 May 25. doi:  10.1155/2015/105172
PMCID: PMC4454762

Neural Differentiation of Human Pluripotent Stem Cells for Nontherapeutic Applications: Toxicology, Pharmacology, and In Vitro Disease Modeling

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To date, the only reported study on the use of small molecules for directing hPSCs differentiation into GABAergic neurons involved combined transient stimulation of muscarinic and GluR1 receptors with their respective small molecule agonists [27]. Although there was inhibition of overall neurogenesis, enhanced differentiation into immature GABAergic neurons was observed. Other studies utilizing protein-based growth factors have reported that Activin A [34], Sonic Hedgehog (SHH), and DKK1 protein [35, 36] could drive PSCs differentiation into GABAergic neurons. It is probable that, in the future, these protein-based growth factors could be substituted with small molecules that activate similar signaling pathways.

[27] R. A. Samarasinghe, P. S. Kanuparthi, J. Timothy Greenamyre, D. B. DeFranco, and R. di Maio, “Transient muscarinic and glutamatergic stimulation of neural stem cells triggers acute and persistent changes in differentiation,” Neurobiology of Disease, vol. 70, pp. 252–261, 2014.
[34] C. Arber, S. V. Precious, S. Cambray et al., “Activin A directs striatal projection neuron differentiation of human pluripotent stem cells,” Development, vol. 142, no. 7, pp. 1375–1386, 2015.
[35] A. D. Carri, M. Onorati, M. J. Lelos et al., “Developmentally coordinated extrinsic signals drive human pluripotent stem cell differentiation toward authentic DARPP-32+ medium-sized spiny neurons,” Development, vol. 140, no. 2, pp. 301–312, 2013.
[36] T. Vazin, R. S. Ashton, A. Conway et al., “The effect of multivalent Sonic hedgehog on differentiation of human embryonic stem cells into dopaminergic and GABAergic neurons,” Biomaterials, vol. 35, no. 3, pp. 941–948, 2014.