Living functional hydrogels generated by bioorthogonal cross-linking reactions of azide-modified cells with alkyne-modified polymers.

To date, many scientists have thoroughly investigated both cells and cellular functions, resulting in the identification of numerous molecular mechanisms underlying the cellular functions. Based on these findings, medical scientists and pharmacologists have developed many technological applications for cells and cellular functions in medicine. How can material scientists utilize cells and cellular functions? Here, we show a concept for utilizing cells and their functions from the viewpoint of materials science. In particular, we develop cell cross-linked living bulk hydrogels by bioorthogonal click cross-linking reactions of azide-modified mammalian cells with alkyne-modified biocompatible polymers. Importantly, we demonstrate the unique functionalities of the living hydrogels, originating from the basic functions of the cells incorporated in the living hydrogels as active cross-linking points. The findings of this study provide a promising route to generating living cell-based next-generation innovative materials, technologies, and medicines.