A SupraGel for efficient production of cell spheroids

Cell spheroids are markedly more representative of the native tissue and the in vivo environment than traditional two-dimensional (2D) cultured cells, thus offering tremendous potential in cell biology research, tissue engineering, and drug screening. Therefore, it is crucial to develop materials and methods for efficient production of cell spheroids. However, currently developed materials, including natural and synthetic hydrogels, present drawbacks, such as undefined ingredients and imperfect biocompatibility, which hinder their widespread application. In this study, we have rationally designed biotinylated peptides that can self-assemble into supramolecular hydrogels (termed SupraGel) for 3D cell culture. The introduction of one D-amino acid in the peptide may decrease cell-matrix interactions, thus facilitating spontaneous cell spheroid formation. Two cancer cell lines, MCF-7 and 4T1, and intestinal stem cells (ISCs) can efficiently divide into cell spheroids when cultured in SupraGel. The reversible shear-thinning and recovery behavior of SupraGel is highly suitable for live-cell embedding and cell spheroid harvesting. The mechanical properties of SupraGel can be easily tuned by adjusting the peptide concentration, thus enabling its suitability for the 3D culture of diverse cell spheroids. We envision the significant potential of our SupraGel for applications in cell therapy, regenerative medicine, and drug screening.