Xeno-free and transgene-free reprograming of mesenchymal stem cells toward neural progenitor cells
Disclosed herein are methods and materials for transdifferentiating mesenchymal stem cells into neural progenitor cells.
1 . A method of reprogramming mesenchymal stem cells as neural progenitor cells, the method comprising (a) modifying epigenetic status of mesenchymal stem cells by (i) subjecting the mesenchymal stem cells to a first media comprising 5-aza-2′-deoxycytidine; (ii) removing the first media from the mesenchymal stem cells, and (iii) subjecting the mesenchymal stem cells from step (ii) to a second media comprising SB431542; and (b) contacting the mesenchymal stem cells of step (a) with extracellular vesicles obtained from neural stem cells under conditions to allow the mesenchymal stem cells to convert into neural progenitor cells.
2 . The method of claim 1 , wherein contacting step (b) comprises (iv) culturing the mesenchymal stem cells in media with neural stem cell (NSC) exosomes for 1-5 days; after step (iv), (v) refreshing the media and NSC exosomes and culturing the cells for 5-15 days; and after step (v), (vi) providing fresh media lacking NSC exosomes and culturing the cells for at least 5-7 days, wherein the cells of step (vi) form spheres.
3 . The method of claim 2 , further comprising isolating spheres from step (vi).
4 . The method of claim 2 , wherein step (v) starts at day 4, 5, or 6 from the start of step (iv); and step (vi) starts at day 14, 15, or 16 from the start of step (a).
5 . The method of claim 1 , wherein contacting step (b) results in formation of spheres, and the method further comprises (c) isolating the spheres.
6 . The method of claim 1 , wherein the extracellular vesicles comprise exosomes.