Surfaces with aligned features, such as microgrooves, can induce the reprogramming of non-germ cells into an embryonic-like state from which they can become any cell type, reports a study published online this week in Nature Materials. Such surface-mediated regulation of cell reprogramming offers ways to improve reprogramming efficiency, advance stem-cell technologies and optimize biomaterials for cell-engineering applications.

Reprogramming somatic, or non-germ, cells into induced pluripotent stem cells is routinely accomplished by using a cocktail of small molecules that induce the expression of a few proteins that control the transcription of pluripotency genes.

Song Li and colleagues demonstrate that reprogramming can be achieved more efficiently by culturing the cells on cell-adhesive substrates with aligned microgrooves or nanofibres, and that these can substitute for the effects of potent small-molecule modifiers of gene expression. The researchers also show that the micro- and nanopatterned substrates increase the expression of pluripotency genes by inducing the cells to acquire an elongated shape, which in turn alters the levels of specific chemical markers in DNA-packaging proteins.